Table of Contents

As filed with the Securities and Exchange Commission on April 2, 2013March 21, 2014

Registration No. 333-187273333-        

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

WASHINGTON,Washington, D.C. 20549

PRE-EFFECTIVE AMENDMENT NO. 1

TO

FORM S-3

REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933

SUNSHINE HEART, INC.

 (Exact(Exact name of registrant as specified in its charter)

12988 Valley View Road

Eden Prairie, MN 55344

(952) 345-4200

(Address, including zip code, and telephone number, including area code, of

registrant’s principal executive offices)

David A. Rosa

Chief Executive Officer

Sunshine Heart, Inc.

12988 Valley View Road

Eden Prairie, MN 55344

(952) 345-4200

(Name, address, including zip code, and telephone number, including area code,

of agent for service)

With a copy to:

Phillip D. Torrence, Esq.

Honigman Miller Schwartz and Cohn LLP

350 East Michigan Avenue, Suite 300

Kalamazoo, MI 49007

(269) 337-7702

Approximate date of commencement of proposed sale to the public: From time to time after the effective date of this Registration Statement.registration statement.

If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box.  o

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box.  x

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  o

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  o

If this Form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box.  o

If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box.  o

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act.

CALCULATION OF REGISTRATION FEE

(1)             There are being registered hereunder such indeterminate number of shares of common stock and preferred stock, such indeterminate number of warrants to purchase common stock, preferred stock or debt securities, and such indeterminate principal amount of debt securities, as shall have an aggregate initial offering price not to exceed $75,000,000,$100 million, less the aggregate dollar amount of all securities previously issued hereunder. If any debt securities are issued at an original issue discount, then the offering price of such debt securities shall be in such greater principal amount as shall result in an aggregate offering price not to exceed $75,000,000,$100 million, less the aggregate dollar amount of all securities previously issued hereunder. In addition, up to 1,513,006 shares of common stock may be sold from time to time pursuant to this registration statement by the selling stockholders named herein.  Any securities registered hereunder may be sold separately or in combination with any of the other securities registered hereunder.  The securities registered hereunder also include such indeterminate number of shares of common stock and preferred stock and amount of debt securities as may be issued upon conversion of or exchange for preferred stock or debt securities that provide for conversion or exchange, upon exercise of warrants or pursuant to the antidilution provisions of any of such securities. In addition, pursuant to Rule 416 under the Securities Act of 1933, as amended, (the “Securities Act”), the shares being registered hereunder include such indeterminate number of shares of common stock and preferred stock as may be issuable with respect to the shares being registered hereunder as a result of stock splits, stock dividends or similar transaction.transactions.

(2)             The proposed maximum offering price per unit of each class of security registered hereunder will be determined from time to time by the registrant in connection with, and at the time of, the issuance of the securities registered hereunder, and is not specified as to each class of security pursuant to General Instruction II.D. of Form S-3, under the Securities Act.as amended.

(3)Pursuant to General Instruction I.B.6. of Form S-3, if the aggregate market value of the registrant’s outstanding voting and non-voting common equity held by non-affiliates of the registrant does not equal or exceed $75,000,000 subsequent to the effective date of this Registration Statement, then the aggregate offering price of all types of securities that the registrant may issue in primary offerings pursuant to this Registration Statement in any 12-month period may not exceed one-third of the aggregate market value of the voting and non-voting common equity held by non-affiliates of the registrant.  In the event that subsequent to the effective date of this Registration Statement, the aggregate market value of the registrant’s outstanding voting and non-voting common equity held by non-affiliates equals or exceeds $75,000,000, then the one-third limitation on sales set forth in the preceding sentence shall not apply to additional sales made in primary offerings pursuant to this Registration Statement.

(4)             Calculated pursuant to Rule 457(o) under the Securities Act of 1933, as amended, based on the proposed maximum aggregate offering price of all securities listed. Amount previously paid.

(4)With respect to shares of common stock to be offered by the selling stockholders in the secondary offering, the price has been estimated solely for the purpose of calculating the registration fee, pursuant to Rule 457(c) under the Securities Act of 1933, as amended, based on the average of the high and low prices reported for the shares of common stock as reported on the NASDAQ Capital Market on March 18, 2014.

The registrant hereby amends this Registration Statementregistration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this Registration Statementregistration statement shall thereafter become effective in accordance with Sectionsection 8(a) of the Securities Act of 1933 or until this Registration Statementthe registration statement shall become effective on such date as the Securities and Exchange Commission acting pursuant to said Sectionsection 8(a), may determine.

Table of Contents

EXPLANATORY NOTE

This registration statement contains two prospectuses:

·a base prospectus which covers both (i) the offering and sale by us of up to $100 million of our common stock, preferred stock, warrants and debt securities and (ii) the resale by selling stockholders of up to an aggregate of 1,513,006 shares of our common stock issued or issuable upon the exercise of options and warrants previously issued; and

·a sales agreement prospectus covering the offering and sale of up to $40 million of our common stock that may be issued and sold under a sales agreement with Cowen and Company, LLC.

The base prospectus immediately follows this explanatory note.  The sales agreement prospectus immediately follows the base prospectus.  The common stock that may be offered and sold under the sales agreement prospectus is included in the $100 million of securities that may be offered and sold by us under the base prospectus.

Table of Contents

SUMMARY

Because this is only a summary, it does not contain all of the information that may be important to you. Before you invest, you should carefully read the more detailed information contained in this prospectus and the information incorporated in this prospectus by reference. Our business involves significant risks. You should carefully consider the information under the heading “Risk Factors” beginning on page 10.9.

As used in this prospectus, unless otherwise indicated, the terms “we,” “us,” “our Company,” “the Company” and “Sunshine Heart” refer to Sunshine Heart, Inc., a Delaware corporation.corporation, and its subsidiaries.

All references in this prospectus to “$” are to U.S. Dollars and all references to “A$” are to Australian Dollars.

C-Pulse®, Sunshine®, Sunshine HeartTM, C-PatchTM and other trademarks or service marks of Sunshine Heart appearing in this prospectus are the property of Sunshine Heart. Trade names, trademarks and service marks of other companies appearing in this registration statement are the property of the respective owners.

We obtained industry and market data used throughout this prospectus through our research, surveys and studies conducted by third parties and industry and general publications. We have not independently verified market and industry data from third-party sources.

Our Company

Overview

We are an early-stage medical device company focused on developing, manufacturing and commercializing our C-PulseC-Pulse® Heart Assist System (the “C-Pulse System”) for treatment of Class III and ambulatory Class IV heart failure. The C-Pulse System utilizes the scientific principles of intra-aortic balloon counter-pulsation applied in an extra-aortic approach to assist the left ventricle by reducing the workload required to pump blood throughout the body, while increasing blood flow to the coronary arteries.

We are in the process of pursuing regulatory approvals necessary to sell our system in the United States. We completed enrollment of our North American feasibility clinical trialstudy in the first half of 2011. In November 2011, we announced the preliminary results of the six-month follow-up period for the feasibility study and we submitted the clinical data to the United StatesU.S. Food and Drug Administration (the “FDA”). In March 2012, the FDA notified us that it completed its review of the C-Pulse System feasibility trialstudy data, concluded we met the applicable agency requirements, and indicated that we can move forward with an investigational device exemption (“IDE”) application. In October 2012, we announced the results of the twelve-month12-month follow-up period for the feasibility study.  In November 2012, the FDA provided us with unconditional approval to initiate a pivotal trial.study.  Enrollment of our COUNTER HF™ pivotal study commenced in September 2013.  We currently anticipate that enrollment of our pivotal trial will begin during the first half of 2013.  We expect to complete enrollment of our pivotal trial by the end of 2015study in 2016 and do not anticipate marketing our system in the United States before 2017.

We obtained CE Mark approval for the C-Pulse System in July 2012 and have taken initial steps to evaluate the market potential for our system in targeted countries that accept the CE Mark in anticipation of commencing commercial sales. In order to gain additional clinical data and support reimbursement in Europe, we alsohave initiated a post-market study in Europe which may include data from other geographies (e.g., Canada) that will evaluate endpoints similar to those for our U.S. pivotal study and enrollment under this study commenced in the second quarter of 2013. We do not currently plan to commercialize the C-Pulse System in any European country unless the product is approved for reimbursement. We do not expect to initiatereceive reimbursement in Germany before 2015 and cannot be certain of when, or if, we will receive reimbursement in Germany or other targeted countries.

We incurred net losses of $21.8 million and $14.1 million in the years ended December 31, 2013 and 2012, respectively. Historically, sales of the C-Pulse System to hospitals and clinics under contract in conjunction with our North American FDA clinical studies have generated all of our revenue.  Our C-Pulse System is not approved for commercial sale. However, the FDA has assigned the C-Pulse System to a post-market trial in EuropeCategory B designation, making it eligible for reimbursement at certain U.S. sites during our clinical studies.  Consequently, upon implant of our C-Pulse System, we are able to invoice hospitals and clinics that will evaluateare eligible for reimbursement by Medicare,

2

Table of Contents

endpoints similar to those for our U.S. pivotal trial. We do not expect to receive reimbursement in Germany before 2014 and cannot be certain of when we will receive reimbursement in other targeted countries.

We incurred net losses of $14.1 million and $16.2 million in the years ended December 31, 2012 and 2011, respectively. Historically, we have generated our revenue solely from sales of the C-Pulse System to hospitals and clinics pursuant to research arrangements and with appropriate regulatory approvals for sales in conjunction with our feasibility clinical trial.Medicaid or private insurance companies. We expect to continue to incur significant net losses as we continue to conduct clinical trialsstudies and pursue commercialization, and as we ramp up sales of our system.

Our Market Opportunity

Heart failure is one of the leading causes of death in the United States and other developed countries. The American Heart Association estimates that 5.7 million people in the United States age 20 and over are affected by heart failure, with an estimated 670,000 new cases diagnosed each year. Nearly 30% of heart failure patients are below the age of 60, and congestive heart failure is the highest U.S. chronic health care expense category.

Heart failure is a progressive disease caused by impairment of the left heart’s ability to pump blood to the various organs of the body. Patients with heart failure commonly experience shortness of breath, fatigue, difficulty exercising and swelling of the legs. The heart becomes weak or stiff and enlarges over time, making it harder for the left heart to pump the blood needed for the body to function properly. The severity of heart failure depends on how well a person’s heart is able to pump blood throughout the body. A common measure of heart failure severity is the New York Heart Association ((the “NYHA”) Class guideline. Patients are classified in Classes I through IV based on their symptoms and functional limitations. Classes I and II include patients with mild heart failure, patients, Class III includeswith moderate heart failure, patients, and Class IV includeswith severe heart failure patients.failure.

Our C-Pulse System targetsis intended for NYHA Class III and ambulatory Class IV patients as defined by the NYHA.patients. It is estimated that approximately 1.5 million heart failure patients in the United States fall into this classification range, and we believe approximately 3.7 million patients in Europe are similarly affected.

Treatment alternatives currently available for Class III heart failure patients in the United States consist primarily of pharmacological therapies and pacing devices that are designed to address heart rhythm issues. Although these treatments may provide symptomatic relief and prolong the life of patients, they do not often halt the progression of congestive heart failure. Circulatory assist devices, specifically left ventricular assist devices (“LVADs”) have been used to treat Class IV patients in the United States, and one product received FDA approval in the United States for Class IIIb patients although the device is not reimbursed by the Centers for Medicare and Medicaid Services for Class IIIb patients. These devices are designed to take over some or all of the pumping function of the heart by mechanically pumping blood into the aorta. Although such products are effective in increasing blood flow, by design these devices are in contact with the patient’s bloodstream, increasing the risk of adverse events, including thrombosis, bleeding and neurologic events.

Our Strategy

Our goal is to become a market leader in the treatment of moderate to severe heart failure patients through the commercialization of our C-Pulse System, and to continue the development of the system to make it safer and more convenient for patients and physicians. We believe that our technology will provide us with a competitive advantage in the market for treating specific segments of heart failure patients. To achieve our objectives, we intend to:

·Conduct a Pivotal Study in the United States - We completed enrollment of the North American feasibility clinical study in the first half of 2011. In November 2011, we announced the preliminary results of the six-month follow-up period for our North American feasibility clinical study and we submitted the clinical data to the FDA. In March 2012, the FDA notified us that it completed its review of the C-Pulse System feasibility study data, concluded we met the applicable agency requirements, and indicated that we can move forward with an IDE application. In November 2012, the FDA provided us with unconditional approval to initiate a pivotal study.  We commenced enrollment in our COUNTER HF pivotal study in the third quarter of 2013, and currently expect to complete it in 2016.

·Conduct a Post-Market Study in Europe to Gain Additional Clinical Data - We have retained consultants to analyze the conditions in various European countries for potential reimbursement for our system and the capabilities of existing hospitals and clinics to implant the C-Pulse System properly and understand the potential benefits of our system. We are targeting the leading LVAD/transplant centers to gain support, promote our technology, and conduct a non-randomized post-market study, the OPTIONS HF study, that will evaluate endpoints similar to those for our U.S. pivotal study to aid our

3

Table of Contents

reimbursement efforts and gain additional clinical data. We commenced enrollment in second quarter of 2013 and expect to complete enrollment in this study in 2014 in our initial target markets.

·                  conductPrepare for the Commercial Launch of the C-Pulse System in Europe - We obtained CE Mark approval for the C-Pulse System in July 2012 and have taken initial steps to evaluate the market potential for our system in targeted countries in Europe in anticipation of commencing commercial sales. We initially plan to sell the C-Pulse System in Europe directly and through experienced distributors in countries where our system is approved for reimbursement or where we otherwise believe there might be a pivotal trialpotentially profitable market for our system. We expect our initial sales efforts in Europe will focus on Germany and Italy, which we believe are the largest potential markets for the C-Pulse System in Europe and have supported reimbursement for heart failure technologies in the United States;past. We do not expect to receive reimbursement in Germany before 2015 and cannot be certain of when, or if, we will receive reimbursement in Germany or other targeted countries.

·                  conduct a post-market trial in EuropeContinue to gain additional clinical data;

·prepare for commercial launch ofEnhance the C-Pulse System in Europe; and

· - We believe it will be important to continue to enhancerefining the C-Pulse System.System to make it more appealing for both patients and physicians. Since completing our 20-patient North American feasibility study, we have made several improvements to the C-Pulse System based on the feasibility study outcomes and feedback we received from surgeons and patients during the study. These changes include enhancements to our driver, cuff, and Percutaneous Interface Leads (“PIL”), among others. We have also completed initial animal studies of a next-generation, fully-implantable C-Pulse System, which would eliminate the risk of exit-site infections.

Our System

The C-Pulse System utilizes the scientific principles of intra-aortic balloon counter-pulsation applied in an extra-aortic approach to assist the left ventricle by reducing the workload required to pump blood throughout the body, while increasing blood flow to the coronary arteries. Combined, these potential benefits may help sustain the patient’s current condition or, in some cases, reverse the heart failure process, thereby potentially preventing the need for later-stage heart failure devices, such as LVADs or artificial hearts, or for transplants. It may also provide relief from the symptoms of Class III and ambulatory Class IV heart failure, and improve quality of life and cardiac function. Based on the patient results from our feasibility trial,study, we also believe that some patients treated with our C-Pulse System will be able to stop using the device due to sustained improvement in their conditions as a result of the therapy.

Once implanted, the C-Pulse cuff is positioned on the outside ofaround the patient’s ascending aorta above the aortic valve. An electrocardiogram sensing lead is then attached to the heart to determine timing for cuff inflation and deflation in synchronization with the heartbeat. As the heart fills with blood, the C-Pulse cuff inflates to push blood from the aorta to the rest of the body and to the heart muscle via the coronary arteries. Just before the heart pumps, the C-Pulse cuff deflates to reduce the heart’s workload through pressure changes, allowing the heart to pump with less effort. The C-Pulse cuff and electrical leads are connected to a single line that is run through the abdominal wall to connect to a power driver outside the body. The system’s single unit driver and battery source are contained inside a carrying bag.

Surgeons in the feasibility phase of our clinical trialstudy initially implanted the C-Pulse System in patients via a full sternotomy and then via a mini-thoracotomy. During the feasibility study, this minimally invasive procedure was developed to allow the C-Pulse System to be implanted via a small pacemaker-like incision between the patient’s ribs and sternum, rather than through a full sternotomy, and thesternotomy. The first implant using this less invasive procedure was completed in 2010. Patients implanted via our minimally invasive procedure typically require a hospital stay of four to seven days in connection with implantation of the C-Pulse System, after which they return home. This compares to an average hospital stay of 14 days for patients implanted with the C-Pulse System via a full sternotomy.  Further, final clinical data from two LVAD studies indicate median hospital stays of 19 and 25 days for patients implanted via a full sternotomy. Therefore, we believe this less invasive approach can reduce procedural time, hospital stays, overall cost and patient risk as compared to treatment options that require a full sternotomy.

The C-Pulse System distinguishes itself from other mechanical heart failure therapies in two important respects,aspects, which we believe differentiate our system from other products addressing moderate to severe heart failure patients.  First, the C-Pulse System is placed outside a patient’s vascular system.  The C-Pulse cuff is placed outsidearound a

4

Table of Contents

On September 30, 2011, we filed a Form 10 registration statement with the SEC, which was declared effective on February 14, 2012. The Form 10 registered our common stock under the Securities Exchange Act of 1934, as amended (the “Exchange Act”). Our common stock began trading on NasdaqNASDAQ on February 16, 2012.

On February 5, 2013, we received conditional approval from the ASX to delist from the official list of the ASX. The delisting is expected to occuroccurred at the close of trading on May 6, 2013.

Our principal executive offices are located at 12988 Valley View Road, Eden Prairie, Minnesota 55344, and our telephone number is (952) 345-4200. Our website address is www.sunshineheart.com. The information on, or that may be accessed through, our website is not incorporated by reference into and should not be considered a part of this prospectus or the registration statement of which it is a part.prospectus.

We qualify as an “emerging growth company” as defined in the Jumpstart ourOur Business Startups Act of 2012 (the “JOBS Act”). An emerging growth company may take advantage of specified reduced reporting and other burdens that are otherwise applicable generally to U.S. public companies. These provisions include:

·                  a requirement to have only two years of audited financial statements and only two years of related Management’s Discussion and Analysis of Financial Condition and Results of Operations disclosure; and

·                  an exemption from the auditor attestation requirement in the assessment of our internal control over financial reporting pursuant to the Sarbanes-Oxley Act of 2002.

We may take advantage of these provisions for up to five years or such earlier time that we are no longer an emerging growth company. We will cease to be an emerging growth company if we have more than $1 billion in annual revenue, have more than $700 million in market value of our shares of common stock held by non-affiliates, or issue more than $1 billion of non-convertible debt over a three-year period. We may choose to take advantage of some but not all of these reduced burdens. TheIn addition, the JOBS Act permits emerging growth companies to take advantage of an extended transition period to comply with new or revised accounting standards applicable to U.S. public companies. We have elected to take advantage of the benefits of this extended transition period, and as a result of this election, our financial statements may not be comparable to those of companies that comply with new or revised accounting standards for U.S. public companies.

The Securities We or the Selling Stockholders May Offer

We may offer shares of our common stock and preferred stock, warrants and/or debt securities, either individually or in combination, with a total value of up to $75$100 million, and the selling stockholders may offer shares of our common stock issued or issuable upon the exercise of options and warrants previously issued, from time to time at prices and on terms to be determined by market conditions at the time of the offering.  This prospectus provides you with a general description of the securities we and/or the selling stockholders, as applicable, may offer. Each time we and/or the selling stockholders, as applicable, offer a type or series of securities, we will provide a prospectus supplement that will describe the specific amounts, prices and other important terms of the securities, including, to the extent applicable:

·                  designation or classification;

6

Table of Contents

·                  redemption, conversion, exercise, exchange, settlement or sinking fund terms, if any;

·                  conversion, exchange or settlement prices or rates, if any, and, if applicable, any provisions for changes to or adjustments in the conversion, exchange or settlement prices or rates and in the securities or other property receivable upon conversion, exchange or settlement;

·                  ranking;

·                  restrictive covenants, if any;

·                  voting or other rights, if any; and

·                  certain federal income tax considerations.

A prospectus supplement and any related free writing prospectus may also add, update or change information contained in this prospectus or in documents we have incorporated by reference into this prospectus. However, no prospectus supplement or free writing prospectus shall offer a security that is not registered and described in this prospectus at the time of the effectiveness of the registration statement of which this prospectus is a part.

This prospectus may not be used to offer or sell any securities unless accompanied by a prospectus supplement.

We and/or the selling stockholders, as applicable, may sell the securities directly or through underwriters, dealers or agents.  We and/or the selling stockholders and such underwriters, dealers or agents, reserve the right to accept or reject all or part of any proposed purchase of securities. If we and/or the selling stockholders do offer securities through underwriters or agents, we will include in the applicable prospectus supplement:

·                  the names of those underwriters or agents;

·    ��             applicable fees, discounts and commissions to be paid to them;

·                  details regarding over-allotment options, if any; and

·                  the net proceeds to us.

Common Stock

We may issue shares of our common stock from time to time. Holders of our common stock are entitled to one vote per share for the election of directors and on all other matters that require stockholder approval, as further set forth herein under the heading “Description of Common Stock.”  Subject to any preferential rights of any then outstanding preferred stock, in the event of our liquidation, dissolution or winding up, holders of our common stock are entitled to share ratably in the assets remaining after

7

Table of Contents

RISK FACTORS

InvestingBefore making an investment decision, you should carefully consider the risks described under “Risk Factors” in the applicable prospectus supplement, together with all of the other information appearing in this prospectus or incorporated by reference into this prospectus and any applicable prospectus supplement, in light of your particular investment objectives and financial circumstances.  Our business, financial condition or results of operations could be materially adversely affected by any of these risks.  The trading price of our securities involvescould decline due to any of these risks, and you may lose all or part of your investment.  This prospectus and the incorporated documents also contain forward-looking statements that involve risks and uncertainties.  Our actual results could differ materially from those anticipated in these forward-looking statements as a high degreeresult of risk.certain factors, including the risks mentioned elsewhere in this prospectus.  You should review carefullyalso consider the risks, uncertainties and uncertaintiesassumptions discussed under the heading “Risk Factors” containedincluded in our most recent annual reportAnnual Report on Form 10-K, which has been filedis on file with the SEC and is incorporated herein by reference, in this prospectus, as well as any updates thereto contained in subsequent filingsand which may be amended, supplemented or superseded from time to time by other reports we file with the SEC or any applicable prospectus supplement or free writing prospectus, before deciding whether to purchase any ofin the securities being registered pursuant to the registration statement of which this prospectus is a part. Each of the risk factors could adversely affect our business, operating results and financial condition, as well as adversely affect the value of an investment in our securities, and the occurrence of any of these risks might cause you to lose all or a part of your investment. Moreover, the risks described are not the only risks that we face. Additional risks not presently known to us or that we currently believe are immaterial may also significantly impair our business operations.future.

FORWARD-LOOKING STATEMENTS

The SEC encourages companies to disclose forward-looking information so that investors can better understand a company’s future prospects and make informed investment decisions. This prospectus contains such “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. These statements may be made directly in this prospectus, and they may also be made a part of this prospectus by reference to other documents filed with the SEC, which is known as “incorporation by reference.”

Words such as “may,” “anticipate,” “estimate,” “expects,” “projects,” “intends,” “plans,” “believes” and words and terms of similar substance used in connection with any discussion of future operating or financial performance identify forward-looking statements. All forward-looking statements are management’s present expectations of future events and are subject to a number of risks and uncertainties that could cause actual results to differ materially from those described in the forward-looking statements. Forward-looking statements might include one or more of the following:

·                  anticipated results of financing activities;

·                  anticipated agreements with marketing partners;

·                  anticipated clinical trialstudy timelines or results;

·                  anticipated research and product development results;

·                  projected regulatory timelines;

·                  descriptions of plans or objectives of management for future operations, products or services;

·                  forecasts of future economic performance;

·anticipated ability to utilize the equity line of credit facility with Aspire Capital Fund, LLC, an Illinois limited liability company, pursuant to that certain Common Stock Purchase Agreement dated January 15, 2013; and

·                  descriptions or assumptions underlying or relating to any of the above items.

10

Table of Contents

Sunshine Heart or to any person acting on its behalf are expressly qualified in their entiretyentireties by the cautionary statements contained or referred to in this section.

RATIOS OF EARNINGS TO FIXED CHARGES

If we offer debt securities and/or preference equity securities under this prospectus, then we will, if required at that time, provide a ratio of earnings to fixed charges and/or ratio of combined fixed charges and preference dividends to earnings, respectively, in the applicable prospectus supplement for such offering.

USE OF PROCEEDS

Unless otherwise provided inWe will retain broad discretion over the applicable prospectus supplement, we intend to use of the net proceeds from theour sale of securities offered hereby. Except as described in any prospectus supplement, we currently anticipate using the net proceeds from our sale of securities under this prospectusoffered hereby primarily for general corporate purposes, including the further development, manufacture and commercialization of our C-Pulse System and for other working capital expenditures.

In the case of sales by the selling stockholders, we will not receive any of the proceeds from such sales; however, we may receive proceeds from cash payments made in connection with the exercise of options and warrants held by the selling stockholders that are covered by this prospectus.

DESCRIPTION OF COMMON STOCK

The following description of our common stock is a summary only and is qualified in its entirety by reference to our certificate of incorporation and bylaws, both of which are exhibits to the registration statement of which this prospectus is a part, and have been filed with the SEC and are available at the SEC’s website at www.sec.gov.

General Terms

We have authority to issue up to 100,000,000 shares of common stock, par value $0.0001 per share. As of April 1, 2013,March 18, 2014, we had 9,509,86716,872,698 shares of our common stock outstanding.  All outstanding shares of our common stock are fully paid and non-assessable.

The transfer agent and registrar for transfers of shares of our common stock is American Stock Transfer & Trust Company, LLC.

The rights, preferences and privileges of the holders of our common stock are subject to, and may be adversely affected by, the rights of the holders of shares of any series of preferred stock that we may designate and issue in the future.  Subject in all cases to the foregoing limitation, the holders of our common stock have the rights, preferences and privileges below.

11

Table of Contents

Subject to the voting restrictions described above, holders of our common stock may adopt, amend or repeal our bylaws and/or alter certain provisions of our certificate of incorporation with the affirmative vote of the stockholdersholders of at least 66 2/3% of the voting power of all of the then-outstanding shares of our capital stock entitled to vote generally in the election of directors, voting together as a single class, in addition to any vote of the holders of a class or series of our stock required by law or our certificate of incorporation. Those provisions of our certificate of incorporation that may be altered only by the super-majority vote described above relate to:

·                  the number of directors on our board of directors, the classification of our board of directors and the terms of the members of our board of directors;

·                  the limitations on removal of any of our directors described below under “—Anti-Takeover Effects of Certain Provisions of Delaware Law and Our Certificate of Incorporation and Bylaws”;Bylaws, Our Stockholder Rights Plan, and Delaware Law;”

·                  the ability of our directors to fill any vacancy on our board of directors by the affirmative vote of a majority of the directors then in office under certain circumstances;

·                  the ability of our board of directors to adopt, amend or repeal our bylaws and the super-majority vote of our stockholders required to adopt, amend or repeal our bylaws described above;

·                  the limitation on action of our stockholders by written action described below under “—Anti-Takeover Effects of Certain Provisions of Delaware Law and Our Certificate of Incorporation and Bylaws”;Bylaws, Our Stockholder Rights Plan, and Delaware Law;”

·                  the choice of forum provision described below under “—Choice of Forum”;Forum;”

·                  the limitations on director liability and indemnification described below under the heading “Limitation“—Limitation on Liability of Directors and Officers and Indemnification”;Indemnification;” and

·                  the super-majority voting requirement to amend our certificate of incorporation described above.

12

Table of Contents

·                  authorizing our board of directors to issue from time to time any series of preferred stock and fix the voting powers, designation, powers, preferences and rights of the shares of such series of preferred stock;

·                  prohibiting stockholders from acting by written consent in lieu of a meeting;

·                  requiring advance notice of stockholder intention to put forth director nominees or bring up other business at a stockholders’ meeting;

·                  prohibiting stockholders from calling a special meeting of stockholders;

·                  requiring a 66 2/3% super-majority stockholder approval in order for stockholders to alter, amend or repeal certain provisions of our certificate of incorporation;

·                  requiring a 66 2/3% super-majority stockholder approval in order for stockholders to adopt, amend or repeal our bylaws;

·                  providing that, subject to the rights of the holders of any series of preferred stock to elect additional directors under specified circumstances, neither the board of directors nor any individual director may be removed without cause;

·                  creating the possibility that our board of directors could prevent a coercive takeover of our Company due to the significant amount of authorized, but unissued shares of our common stock and preferred stock;

13

Table of Contents

stockholder for a period of three years following the date that the stockholder became an interested stockholder, unless:

·                  prior to that date, our board of directors approved either the business combination or the transaction that resulted in the stockholder becoming an interested stockholder;

·                  upon consummation of the transaction that resulted in the stockholder becoming an interested stockholder, the interested stockholder owned at least 85% of our voting stock outstanding at the time the transaction commenced, excluding for purposes of determining the number of shares outstanding (but not the outstanding voting stock owned by the interested stockholder) those shares owned by (i) persons who are directors and also officers and (ii) employee stock plans in which employee participants do not have the right to determine confidentially whether shares held subject to the plan will be tendered in a tender or exchange offer; or

·                  on or subsequent to that date, the business combination is approved by our board of directors and authorized at an annual or special meeting of stockholders, and not by written consent, by the affirmative vote of at least 66  2/3% of the outstanding voting stock that is not owned by the interested stockholder.

In general, Section 203 of the DGCL defines an interested stockholder as an entity or person beneficially owning 15% or more of the outstanding voting stock of the corporation and any entity or person affiliated with or controlling or controlled by any of these entities or persons.

The above-summarized provisions of the DGCL and our certificate of incorporation and bylaws, the Rights Plan and the above-summarized provisions of the DGCL could make it more difficult to acquire us by means of a tender offer, a proxy contest or otherwise, or to remove incumbent officers and directors. These provisions are expected to discourage certain types of coercive takeover practices and takeover bids that our board of directors may consider inadequate and to encourage persons seeking to acquire control of us to first negotiate with our board of directors. We believe that the benefits of increased protection of our ability to negotiate with the proponent of an unfriendly or unsolicited proposal to acquire or restructure us outweigh the disadvantages of discouraging takeover or acquisition proposals because, among other things, negotiation of these proposals could result in an improvement of their terms.

Choice of Forum

Our certificate of incorporation provides that, unless we consent in writing otherwise, the Court of Chancery of the State of Delaware will be the sole and exclusive forum for any (i) derivative action or proceeding brought on our behalf; (ii) action asserting a breach of fiduciary duty owed by any of our

14

Table of Contents

powers, restrictions, limitations as to dividends or other distributions, qualifications and terms or conditions of redemption for each class or series. Any shares of preferred stock will, when issued, be fully paid and non-assessable.

For any series of preferred stock that we may issue, our board of directors will determine and the prospectus supplement relating to such series will describe:

·                  the title and stated value of the preferred stock;

·                  the number of shares of the preferred stock offered, the liquidation preference per share and the offering price of the preferred stock;

·                  the dividend rate(s), period(s) or payment date(s) or method(s) of calculation applicable to the preferred stock;

·                  whether dividends are cumulative or non-cumulative and, if cumulative, the date from which dividends on the preferred stock will accumulate;

·                  our right, if any, to defer payment of dividends and the maximum length of any such deferral period;

·                  the procedures for auction and remarketing, if any, for the preferred stock;

·                  the provisions for a sinking fund, if any, for the preferred stock;

·                  the provision for redemption, if applicable, of the preferred stock;

·                  any listing of the preferred stock on any securities exchange;

·                  the terms and conditions, if applicable, upon which the preferred stock will be convertible into common stock, including the conversion price or manner of calculation and conversion period;

·                  voting rights, if any, of the preferred stock;

·                  whether interests in the preferred stock will be represented by depositary shares;

17

Table of Contents

DESCRIPTION OF WARRANTS

The following is a general description of the terms of the warrants we may issue from time to time unless we provide otherwise in the prospectus supplement. Particular terms of any warrants we offer will be described in the prospectus supplement relating to such warrants.

General Terms

We may issue warrants to purchase common stock, preferred stock or debt securities. Warrants may be issued independently or together with other securities and may be attached or separate from such securities. We will issue each series of warrants under a separate warrant agreement to be entered into between us and a warrant agent. The warrant agent will act solely as our agent and will not assume any obligation or relationship of agency for or with holders or beneficial owners of warrants.

A prospectus supplement will describe the particular terms of any series of warrants we may issue, including the following:

·                  the title and aggregate number of the warrants;

·                  the price or prices at which the warrants will be issued and the currency or currencies in which the price of the warrants may be payable;

·                  if applicable, the designation and terms of the securities with which the warrants are issued and the number of warrants issued with each such security or each principal amount of such security;

·                  in the case of warrants to purchase debt securities, the principal amount of debt securities purchasable upon exercise of one warrant;

·                  in the case of warrants to purchase common stock or preferred stock, the number of shares of common stock or preferred stock, as the case may be, purchasable upon the exercise of one warrant and the price at which those shares may be purchased upon such exercise;

18

Table of Contents

·                  if applicable, a discussion of any material or special U.S. federal income tax consequences of holding or exercising the warrants; and

·                  any other terms of the warrants, including terms, procedures and limitations relating to the exchange and exercise of the warrants.

We and the warrant agent may amend or supplement the warrant agreement for a series of warrants without the consent of the holders of the warrants issued thereunder to effect changes that are not inconsistent with the provisions of the warrants and that do not materially and adversely affect the interests of the holders of the warrants.

Exercise of Warrants

Each warrant will entitle the holder to purchase for cash such common stock or preferred stock at the exercise price or such principal amount of debt securities as shall in each case be set forth in, or be determinable as set forth in, the prospectus supplement relating to the warrants offered thereby. Warrants may be exercised as set forth in the prospectus supplement beginning on the date specified therein and continuing until the close of business on the expiration date set forth in the prospectus supplement. After the close of business on the expiration date, unexercised warrants will become void.

Upon receipt of the required payment and the warrant certificate properly completed and duly executed at the corporate trust office of the warrant agent or any other office indicated in the applicable prospectus supplement, we will issue and deliver the securities purchasable upon such exercise. If fewer than all of the warrants represented by the warrant certificate are exercised, then we will issue a new warrant certificate for the remaining amount of warrants. If we so indicate in the applicable prospectus

19

Table of Contents

The following summaries of material provisions of the senior debt securities, the subordinated debt securities and the indentures are subject to, and qualified in their entiretyentireties by reference to, all of the provisions of the indenture applicable to a particular series of debt securities. We urge you to read the applicable prospectus supplements and any related free writing prospectuses related to the debt securities that we may offer under this prospectus, as well as the complete indentures that contain the terms of the debt securities. Except as we may otherwise indicate, the terms of the senior indenture and the subordinated indenture are identical.

General

We will describe in the applicable prospectus supplement the terms of the series of debt securities being offered, including:

·                  the title;

·                  the principal amount being offered, and if a series, the total amount authorized and the total amount outstanding;

20

Table of Contents

other restricted payments; sell or otherwise dispose of assets; enter into sale-leaseback transactions; engage in transactions with stockholders and affiliates; issue or sell stock of our subsidiaries; or effect a consolidation or merger;

·                  whether the indenture will require us to maintain any interest coverage, fixed charge, cash flow-based, asset-based or other financial ratios;

·                  a discussion of any material U.S. federal income tax considerations applicable to the debt securities;

21

Table of Contents

·                  if we fail to pay interest when due and payable and our failure continues for 90 days and the time for payment has not been extended or deferred;

22

Table of Contents

These limitations do not apply to a suit instituted by a holder of debt securities if we default in the payment of the principal, premium, if any, or interest on, the debt securities.

We will periodically file statements with the debenture trustee regarding our compliance with specified covenants in the indentures.

Modification of Indenture; Waiver

We and the debenture trustee may change an indenture without the consent of any holders with respect to specific matters:

·                  to fix any ambiguity, defect or inconsistency in the indenture;

·                  to comply with the provisions described above under “Description of Debt Securities—“—Consolidation, Merger or Sale;”

·                  to comply with any requirements of the SEC in connection with the qualification of any indenture under the Trust Indenture Act;

·                  to add to, delete from or revise the conditions, limitations, and restrictions on the authorized amount, terms, or purposes of issue, authentication and delivery of debt securities, as set forth in the indenture;

·                  to provide for the issuance of and establish the form and terms and conditions of the debt securities of any series as provided under “Description of Debt Securities—“—General” to establish the form of any certifications required to be furnished pursuant to the terms of the indenture or any series of debt securities, or to add to the rights of the holders of any series of debt securities;

·                  to evidence and provide for the acceptance of appointment hereunder by a successor trustee;

·                  to provide for uncertificated debt securities in addition to or in place of certificated debt securities and to make all appropriate changes for such purpose;

·                  to add to our covenants such new covenants, restrictions, conditions or provisions for the protection of the holders, and to make the occurrence, or the occurrence and the continuance, of a default in any such additional covenants, restrictions, conditions or provisions an event of default; or

·                  to change anything that does not materially adversely affect the interests of any holder of debt securities of any series.

In addition, under the indentures, the rights of holders of a series of debt securities may be changed by us and the debenture trustee with the written consent of the holders of at least a majority in aggregate principal amount of the outstanding debt securities of each series that is affected. However, unless we provide otherwise in the prospectus supplement applicable to a particular series of debt

24

Table of Contents

Discharge

Each indenture provides that we can elect to be discharged from our obligations with respect to one or more series of debt securities, except for specified obligations, including obligations to:

·                  register the transfer or exchange of debt securities of the series;

·                  replace stolen, lost or mutilated debt securities of the series;

·                  maintain paying agencies;

·                  hold monies for payment in trust;

·                  recover excess money held by the debenture trustee;

·                  compensate and indemnify the debenture trustee; and

·                  appoint any successor trustee.

In order to exercise our rights to be discharged, we must deposit with the debenture trustee money or government obligations sufficient to pay all the principal of, any premium, if any, and interest on, the debt securities of the series on the dates payments are due.

Form, Exchange and Transfer

We will issue the debt securities of each series only in fully registered form without coupons and, unless we provide otherwise in the applicable prospectus supplement, in denominations of $1,000 and any integral multiple thereof. The indentures provide that we may issue debt securities of a series in temporary or permanent global form and as book-entry securities that will be deposited with, or on behalf of, The Depository Trust Company (“DTC”) or another depositary named by us and identified in a prospectus supplement with respect to that series. See “Legal Ownership of Securities” for a further description of the terms relating to any book-entry securities.

At the option of the holder, subject to the terms of the indentures and the limitations applicable to global securities described in the applicable prospectus supplement, the holder of the debt securities of any series can exchange the debt securities for other debt securities of the same series, in any authorized denomination and of like tenor and aggregate principal amount.

Subject to the terms of the indentures and the limitations applicable to global securities set forth in the applicable prospectus supplement, holders of the debt securities may present the debt securities for

25

Table of Contents

securities that may be selected for redemption and ending at the close of business on the day of the mailing; or

·                  register the transfer of or exchange any debt securities so selected for redemption, in whole or in part, except the unredeemed portion of any debt securities we are redeeming in part.

Information Concerning the Debenture Trustee

The debenture trustee, other than during the occurrence and continuance of an event of default under an indenture, undertakes to perform only those duties as are specifically set forth in the applicable indenture. Upon an event of default under an indenture, the debenture trustee must use the same degree of care as a prudent person would exercise or use in the conduct of his or her own affairs. Subject to this provision, the debenture trustee is under no obligation to exercise any of the powers given it by the indentures at the request of any holder of debt securities unless it is offered reasonable security and indemnity against the costs, expenses and liabilities that it might incur.

Payment and Paying Agents

Unless we otherwise indicate in the applicable prospectus supplement, we will make payment of the interest on any debt securities on any interest payment date to the person in whose name the debt securities, or one or more predecessor securities, are registered at the close of business on the regular record date for the interest.

We will pay principal of and any premium and interest on the debt securities of a particular series at the office of the paying agents designated by us, except that unless we otherwise indicate in the applicable prospectus supplement, we will make interest payments by check that we will mail to the holder or by wire transfer to certain holders. Unless we otherwise indicate in the applicable prospectus supplement, we will designate the corporate trust office of the debenture trustee in the City of New York as our sole paying agent for payments with respect to debt securities of each series. We will name in the applicable prospectus supplement any other paying agents that we initially designate for the debt securities of a particular series. We will maintain a paying agent in each place of payment for the debt securities of a particular series.

All money we pay to a paying agent or the debenture trustee for the payment of the principal of or any premium or interest on any debt securities that remains unclaimed at the end of two years after such

26

Table of Contents

Special Considerations for Indirect Holders

If you hold securities through a bank, broker or other financial institution, either in book-entry form because the securities are represented by one or more global securities or in street name, you should check with your own institution to find out:

·                  how it handles securities payments and notices;

·                  whether it imposes fees or charges;

·                  how it would handle a request for the holders’ consent, if ever required;

·                  whether and how you can instruct it to send you securities registered in your own name so you can be a holder, if that is permitted in the future;

·                  how it would exercise rights under the securities if there were a default or other event triggering the need for holders to act to protect their interests; and

28

Table of Contents

·                  An investor cannot cause the securities to be registered in his or her name, and cannot obtain non-global certificates for his or her interest in the securities, except in the special situations we describe below.

·                  An investor will be an indirect holder and must look to his or her own bank or broker for payments on the securities and protection of his or her legal rights relating to the securities, as we describe above.

·                  An investor may not be able to sell interests in the securities to some insurance companies and to other institutions that are required by law to own their securities in non-book-entry form.

29

Table of Contents

SELLING STOCKHOLDERS

The selling stockholders may offer and sell from time to time an aggregate of 1,513,006 shares of common stock issued or issuable upon the exercise of certain (i) options previously issued in connection with renounceable rights issues on December 7, 2010 and January 20, 2011 or a private placement on September 9, 2011 and (ii) warrants previously issued in connection with private placements on September 16, 2011 and February 8, 2012.  Additional information about the selling stockholders, where applicable, will be set forth in a prospectus supplement, in a post-effective amendment, or in filings we make with the SEC under the Exchange Act that are incorporated herein by reference.

PLAN OF DISTRIBUTION

We and/or the selling stockholders, if applicable, may sell the securities in one or more of the following ways (or in any combination) from time to time:

·      at a fixed pricethrough underwriters or prices, which may be changed;dealers;

·      at market prices prevailing at the timedirectly to a limited number of sale;

·      at prices relatedpurchasers or to such prevailing market prices;

·      at varying prices determined at the time of sale;a single purchaser; or

·      at negotiated prices.through agents.

AEach time we offer and sell securities under this prospectus, we will file a prospectus supplement. The prospectus supplement or supplements will describestate the terms of the offering of the securities, including:

·the name or names of theany underwriters, dealers or agents participating in agents;

·the offering,purchase price of such securities and the proceeds to be received by the Company, if any;

·      the purchase price of the securities sold by us to any underwriter or dealer and the net proceeds we expect to receive from the offering;

·      any over-allotment options under which underwriters may purchase additional securities from us;

·      any agency fees or underwriting discounts or commissionsagency fees and other items constituting agents’underwriters’ or underwriters’agents’ compensation;

·any initial public offering price;

·any discounts or concessions allowed or reallowed or paid to dealers; and

·any securities exchange or marketexchanges on which the securities may be listed.

Only underwriters named in the prospectus supplement will be underwriters of the securities offered by the prospectus supplement.

If underwriters are used in the sale, they will acquire the securities for their own account and may resell the securities from time to time in one or more transactions at a fixed public offering price or at varying prices determined at the time of sale. The obligations of the underwriters to purchase the securities will be subject to the conditions set forth in the applicable underwriting agreement. We may offer the securities to the public through underwriting syndicates represented by managing underwriters or by underwriters without a syndicate. Subject to certain conditions, the underwriters will be obligated to purchase all of the securities offered by the prospectus supplement, other than securities covered by any over-allotment option. Any initial public offering price and any discounts or commissions or concessions allowed or reallowed or paid to dealers may changebe changed from time to time. We may

If we and/or the selling stockholders, if applicable, use underwriters with whom we have a material relationship. We will describe in the sale, the securities will be acquired by the underwriters for their own account and may be resold from time to time in one or more transactions, including:

·negotiated transactions;

·at a fixed public offering price or prices, which may be changed;

·at market prices prevailing at the time of sale;

·at prices related to prevailing market prices; or

·at negotiated prices.

Unless otherwise stated in a prospectus supplement, naming the underwriter,obligations of the natureunderwriters to purchase any

27

Table of Contents

securities will be conditioned on customary closing conditions and the underwriters will be obligated to purchase all of such series of securities, if any such relationship.are purchased.

We and/or the selling stockholders, if applicable, may sell the securities directly or through agents we designate from time to time. WeThe prospectus supplement will name any agent involved in the offering andoffer or sale of the securities and we will describe any commissions and other compensation we will pay the agent in the prospectus supplement. Unless the prospectus supplement states otherwise, ourto them. Generally, any agent will actbe acting on a best-effortsbest efforts basis for the period of its appointment.

We and/or the selling stockholders, if applicable, may authorize agentsunderwriters, dealers or underwritersagents to solicit offers by certain types of institutional investorspurchasers to purchase the securities from usSunshine Heart at the public offering price set forth in the prospectus supplement pursuant to delayed delivery contracts providing for payment and delivery on a specified date in the future. WeThe contracts will describebe subject only to those conditions set forth in the conditions to these contractsprospectus supplement, and the prospectus supplement will set forth any commissions we must pay for solicitation of these contracts in the prospectus supplement.contracts.

WeUnderwriters and agents may provide agents and underwritersbe entitled under agreements entered into with Sunshine Heart and/or the selling stockholders, if applicable, to indemnification by Sunshine Heart and/or the selling stockholders, if applicable, against certain civil liabilities, related to this offering, including liabilities under the Securities Act, or to contribution with respect to payments thatwhich the underwriters or agents or underwriters may make with respectbe required to these liabilities. Agentsmake. Underwriters and underwritersagents may be customers of, engage in transactions with, or perform services for usSunshine Heart and its affiliates in the ordinary course of business.

AllEach series of securities we may offer, other than common stock, will be a new issuesissue of securities withand will have no established trading market.market other than the common stock which is listed on NASDAQ. Any agents or underwriters to whom securities are sold for public offering and sale may make a market in thesethe securities, but such underwriters will not be obligated to do so and may discontinue any market making at any time without notice. We cannot guarantee the liquidity of the trading markets for any securities. There is currently no market for any of the offeredThe securities, other than ourthe common stock, which ismay or may not be listed on the NASDAQ Capital Market. We have no current plans for listing of the preferred stock, warrants to purchase common stock, preferred stock or debta national securities or debt securities, on any securities exchange or quotation system; any such listing with respect to any particular preferred stock, warrants to purchase common stock, preferred stock or debt securities, or debt securities, will be described in the applicable prospectus supplement or other offering materials, as the case may be.

Any underwriter may engage in overallotment, stabilizing transactions, short covering transactions and penalty bids in accordance with Regulation M under the Exchange Act. Overallotment involves sales in excess of the offering size, which create a short position. Stabilizing transactions permit bids to purchase the underlying security so long as the stabilizing bids do not exceed a specified maximum. Short covering transactions involve purchases of the securities in the open market after the distribution is completed to cover short positions. Penalty bids permit the underwriters to reclaim a selling concession from a dealer when the securities originally sold by the dealer are purchased in a stabilizing or covering transaction to cover short positions. Those activities may cause the price of the securities to be higher than it would otherwise be. If commenced, the underwriters may discontinue any of the activities at any time.

31

Table of Contents

·                  the description of our common stock in our Registration Statementregistration statement on Form 10 filed with the SEC on September 30, 2011, including any amendment or reportreports filed for the purpose of updating such description.description; and

We incorporate by reference ·the documents listed above and any future filings made by usdescription of our Series A Junior Participating Preferred Stock, par value $0.0001 per share, in our registration statement on Form 8-A filed with the SEC underon June 14, 2013.

All documents we file with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act, except as to any portion of any report or document that is not deemed filed under such provisions, (i) on or after the initialdate of filing of the registration statement that containscontaining this prospectus and prior to the terminationeffectiveness of the offeringregistration statement and (ii) on or after the date of this prospectus until the earlier of the date on which all of the securities describedregistered hereunder have been sold or the registration statement of which this prospectus is a part has been withdrawn, shall be deemed incorporated by reference in this prospectus; provided, however, that notwithstandingprospectus and to be a part of this prospectus from the foregoing, unless

32

Table of Contents

SUMMARY

Because this is only a summary, it does not contain all of the information that may be important to you. Before you invest, you should carefully read the more detailed information contained in this prospectus and the information incorporated in this prospectus by reference. Our business involves significant risks. You should carefully consider the information under the heading “Risk Factors” beginning on page S-7.

As used in this prospectus, unless otherwise indicated, the terms “we,” “us,” “our Company,” “the Company” and “Sunshine Heart” refer to Sunshine Heart, Inc., a Delaware corporation, and its subsidiaries.

All references in this prospectus to “$” are to U.S. Dollars.

C-Pulse®, Sunshine®, Sunshine HeartTM, C-PatchTM and other trademarks or service marks of Sunshine Heart appearing in this prospectus are the property of Sunshine Heart. Trade names, trademarks and service marks of other companies appearing in this registration statement are the property of the respective owners.

We obtained industry and market data used throughout this prospectus through our research, surveys and studies conducted by third parties and industry and general publications. We have not independently verified market and industry data from third-party sources.

Our Company

Overview

We are an early-stage medical device company focused on developing, manufacturing and commercializing our C-Pulse® Heart Assist System (the “C-Pulse System”) for treatment of Class III and ambulatory Class IV heart failure. The C-Pulse System utilizes the scientific principles of intra-aortic balloon counter-pulsation applied in an extra-aortic approach to assist the left ventricle by reducing the workload required to pump blood throughout the body, while increasing blood flow to the coronary arteries.

We are in the process of pursuing regulatory approvals necessary to sell our system in the United States. We completed enrollment of our North American feasibility clinical study in the first half of 2011. In November 2011, we announced the preliminary results of the six-month follow-up period for the feasibility study and we submitted the clinical data to the U.S. Food and Drug Administration (the “FDA”). In March 2012, the FDA notified us that it completed its review of the C-Pulse System feasibility study data, concluded we met the applicable agency requirements, and indicated that we can move forward with an investigational device exemption (“IDE”) application. In October 2012, we announced the results of the 12-month follow-up period for the feasibility study.  In November 2012, the FDA provided us with unconditional approval to initiate a pivotal study.  Enrollment of our COUNTER HF™ pivotal study commenced in September 2013.  We currently expect to complete enrollment of our pivotal study in 2016 and do not anticipate marketing our system in the United States before 2017.

We obtained CE Mark approval for the C-Pulse System in July 2012 and have taken initial steps to evaluate the market potential for our system in targeted countries that accept the CE Mark in anticipation of commencing commercial sales. In order to gain additional clinical data and support reimbursement in Europe, we have initiated a post-market study in Europe which may include data from other geographies (e.g., Canada) that will evaluate endpoints similar to those for our U.S. pivotal study and enrollment under this study commenced in the second quarter of 2013. We do not currently plan to commercialize the C-Pulse System in any European country unless the product is approved for reimbursement. We do not expect to receive reimbursement in Germany before 2015 and cannot be certain of when, or if, we will receive reimbursement in Germany or other targeted countries.

We incurred net losses of $21.8 million and $14.1 million in the years ended December 31, 2013 and 2012, respectively. Historically, sales of the C-Pulse System to hospitals and clinics under contract in conjunction with our North American FDA clinical studies have generated all of our revenue.  Our C-Pulse System is not approved for commercial sale. However, the FDA has assigned the C-Pulse System to a Category B designation, making it eligible for reimbursement at certain U.S. sites during our clinical studies.  Consequently, upon implant of our C-Pulse System, we are able to invoice hospitals and clinics that are eligible for reimbursement by Medicare,

S - 2

Table of Contents

Medicaid or private insurance companies. We expect to continue to incur significant net losses as we continue to conduct clinical studies and pursue commercialization, and as we ramp up sales of our system.

Our Market Opportunity

Heart failure is one of the leading causes of death in the United States and other developed countries. The American Heart Association estimates that 5.7 million people in the United States age 20 and over are affected by heart failure, with an estimated 670,000 new cases diagnosed each year. Nearly 30% of heart failure patients are below the age of 60, and congestive heart failure is the highest U.S. chronic health care expense category.

Heart failure is a progressive disease caused by impairment of the left heart’s ability to pump blood to the various organs of the body. Patients with heart failure commonly experience shortness of breath, fatigue, difficulty exercising and swelling of the legs. The heart becomes weak or stiff and enlarges over time, making it harder for the left heart to pump the blood needed for the body to function properly. The severity of heart failure depends on how well a person’s heart is able to pump blood throughout the body. A common measure of heart failure severity is the New York Heart Association (the “NYHA”) Class guideline. Patients are classified in Classes I through IV based on their symptoms and functional limitations. Classes I and II include patients with mild heart failure, Class III with moderate heart failure, and Class IV with severe heart failure.

Our C-Pulse System is intended for NYHA Class III and ambulatory Class IV patients. It is estimated that approximately 1.5 million heart failure patients in the United States fall into this classification range, and we believe approximately 3.7 million patients in Europe are similarly affected.

Treatment alternatives currently available for Class III heart failure patients in the United States consist primarily of pharmacological therapies and pacing devices that are designed to address heart rhythm issues. Although these treatments may provide symptomatic relief and prolong the life of patients, they do not often halt the progression of congestive heart failure. Circulatory assist devices, specifically left ventricular assist devices (“LVADs”) have been used to treat Class IV patients in the United States, and one product received FDA approval in the United States for Class IIIb patients although the device is not reimbursed by the Centers for Medicare and Medicaid Services for Class IIIb patients. These devices are designed to take over some or all of the pumping function of the heart by mechanically pumping blood into the aorta. Although such products are effective in increasing blood flow, by design these devices are in contact with the patient’s bloodstream, increasing the risk of adverse events, including thrombosis, bleeding and neurologic events.

Our Strategy

Our goal is to become a market leader in the treatment of moderate to severe heart failure patients through the commercialization of our C-Pulse System, and to continue the development of the system to make it safer and more convenient for patients and physicians. We believe that our technology will provide us with a competitive advantage in the market for treating specific segments of heart failure patients. To achieve our objectives, we intend to:

·Conduct a Pivotal Study in the United States - We completed enrollment of the North American feasibility clinical study in the first half of 2011. In November 2011, we announced the preliminary results of the six-month follow-up period for our North American feasibility clinical study and we submitted the clinical data to the FDA. In March 2012, the FDA notified us that it completed its review of the C-Pulse System feasibility study data, concluded we met the applicable agency requirements, and indicated that we can move forward with an IDE application. In November 2012, the FDA provided us with unconditional approval to initiate a pivotal study.  We commenced enrollment in our COUNTER HF pivotal study in the third quarter of 2013, and currently expect to complete it in 2016.

·Conduct a Post-Market Study in Europe to Gain Additional Clinical Data - We have retained consultants to analyze the conditions in various European countries for potential reimbursement for our system and the capabilities of existing hospitals and clinics to implant the C-Pulse System properly and understand the potential benefits of our system. We are targeting the leading LVAD/transplant centers to gain support, promote our technology, and conduct a non-randomized post-market study, the OPTIONS HF study, that will evaluate endpoints similar to those for our U.S. pivotal study to aid our

S - 3

Table of Contents

reimbursement efforts and gain additional clinical data. We commenced enrollment in second quarter of 2013 and expect to complete enrollment in this study in 2014 in our initial target markets.

·Prepare for the Commercial Launch of the C-Pulse System in Europe - We obtained CE Mark approval for the C-Pulse System in July 2012 and have taken initial steps to evaluate the market potential for our system in targeted countries in Europe in anticipation of commencing commercial sales. We initially plan to sell the C-Pulse System in Europe directly and through experienced distributors in countries where our system is approved for reimbursement or where we otherwise believe there might be a potentially profitable market for our system. We expect our initial sales efforts in Europe will focus on Germany and Italy, which we believe are the largest potential markets for the C-Pulse System in Europe and have supported reimbursement for heart failure technologies in the past. We do not expect to receive reimbursement in Germany before 2015 and cannot be certain of when, or if, we will receive reimbursement in Germany or other targeted countries.

·Continue to Enhance the C-Pulse System - We believe it will be important to continue refining the C-Pulse System to make it more appealing for both patients and physicians. Since completing our 20-patient North American feasibility study, we have made several improvements to the C-Pulse System based on the feasibility study outcomes and feedback we received from surgeons and patients during the study. These changes include enhancements to our driver, cuff, and Percutaneous Interface Leads (“PIL”), among others. We have also completed initial animal studies of a next-generation, fully-implantable C-Pulse System, which would eliminate the risk of exit-site infections.

Our System

The C-Pulse System utilizes the scientific principles of intra-aortic balloon counter-pulsation applied in an extra-aortic approach to assist the left ventricle by reducing the workload required to pump blood throughout the body, while increasing blood flow to the coronary arteries. Combined, these potential benefits may help sustain the patient’s current condition or, in some cases, reverse the heart failure process, thereby potentially preventing the need for later-stage heart failure devices, such as LVADs or artificial hearts, or for transplants. It may also provide relief from the symptoms of Class III and ambulatory Class IV heart failure, and improve quality of life and cardiac function. Based on the results from our feasibility study, we also believe that some patients treated with our C-Pulse System will be able to stop using the device due to sustained improvement in their conditions as a result of the therapy.

Once implanted, the C-Pulse cuff is positioned around the patient’s ascending aorta above the aortic valve. An electrocardiogram sensing lead is then attached to the heart to determine timing for cuff inflation and deflation in synchronization with the heartbeat. As the heart fills with blood, the C-Pulse cuff inflates to push blood from the aorta to the rest of the body and to the heart muscle via the coronary arteries. Just before the heart pumps, the C-Pulse cuff deflates to reduce the heart’s workload through pressure changes, allowing the heart to pump with less effort. The C-Pulse cuff and electrical leads are connected to a single line that is run through the abdominal wall to connect to a power driver outside the body. The system’s single unit driver and battery source are contained inside a carrying bag.

Surgeons in the feasibility phase of our clinical study initially implanted the C-Pulse System in patients via a full sternotomy and then via a mini-thoracotomy. During the feasibility study, this minimally invasive procedure was developed to allow the C-Pulse System to be implanted via a small pacemaker-like incision between the patient’s ribs and sternum, rather than through a full sternotomy. The first implant using this less invasive procedure was completed in 2010. Patients implanted via our minimally invasive procedure typically require a hospital stay of four to seven days in connection with implantation of the C-Pulse System, after which they return home. This compares to an average hospital stay of 14 days for patients implanted with the C-Pulse System via a full sternotomy.  Therefore, we believe this less invasive approach can reduce procedural time, hospital stays, overall cost and patient risk as compared to treatment options that require a full sternotomy.

The C-Pulse System distinguishes itself from other mechanical heart failure therapies in two important aspects, which we believe differentiate our system from other products addressing moderate to severe heart failure patients.  First, the C-Pulse System is placed outside a patient’s vascular system.  The C-Pulse cuff is placed around a

S - 4

Table of Contents

On September 30, 2011, we filed a Form 10 registration statement with the SEC, which was declared effective on February 14, 2012. The Form 10 registered our common stock under the Securities Exchange Act of 1934, as amended (the “Exchange Act”). Our common stock began trading on NASDAQ on February 16, 2012.

On February 5, 2013, we received conditional approval from the ASX to delist from the official list of the ASX. The delisting occurred at the close of trading on May 6, 2013.

Our principal executive offices are located at 12988 Valley View Road, Eden Prairie, Minnesota 55344, and our telephone number is (952) 345-4200. Our website address is www.sunshineheart.com. The information on, or that may be accessed through, our website is not incorporated by reference into and should not be considered a part of this prospectus.

We qualify as an “emerging growth company” as defined in the Jumpstart Our Business Startups Act of 2012 (the “JOBS Act”). An emerging growth company may take advantage of specified reduced reporting and other burdens that are otherwise applicable generally to U.S. public companies. These provisions include:

·a requirement to have only two years of audited financial statements and only two years of related Management’s Discussion and Analysis of Financial Condition and Results of Operations disclosure; and

·an exemption from the auditor attestation requirement in the assessment of our internal control over financial reporting pursuant to the Sarbanes-Oxley Act of 2002.

We may take advantage of these provisions for up to five years or such earlier time that we are no longer an emerging growth company. We will cease to be an emerging growth company if we have more than $1 billion in annual revenue, have more than $700 million in market value of our shares of common stock held by non-affiliates, or issue more than $1 billion of non-convertible debt over a three-year period. We may choose to take advantage of some but not all of these reduced burdens. In addition, the JOBS Act permits emerging growth companies to take advantage of an extended transition period to comply with new or revised accounting standards applicable to U.S. public companies. We have elected to take advantage of the benefits of this extended transition period, and as a result of this election, our financial statements may not be comparable to those of companies that comply with new or revised accounting standards for U.S. public companies.

The Offering

S - 6

Table of Contents

The number of shares of our common stock shown above to be outstanding after this offering is based on 16,825,284 shares outstanding as of December 31, 2013. The number of shares of our common stock outstanding as of December 31, 2013, as used throughout this prospectus, unless otherwise indicated, excludes:

·1,886,579 shares of our common stock subject to options outstanding having a weighted average exercise price of $8.80 per share as of December 31, 2013;

·restricted stock units representing a total of 84,128 shares of common stock issuable upon vesting as of December 31, 2013;

·1,630,804 shares of our common stock that have been reserved for issuance upon exercise of outstanding warrants having a weighted average exercise price of $6.69 per share as of December 31, 2013.

RISK FACTORS

An investment in our common stock involves a high degree of risk. Before deciding whether to invest in our common stock, you should consider carefully the risks described below and discussed under the sections captioned “Risk Factors” contained in our most recent Annual Report on Form 10-K, as well as our subsequent Quarterly Reports on Form 10-Q, which are incorporated by reference herein in their entireties, together with other information in this prospectus, the information and documents incorporated by reference in this prospectus, and in any free writing prospectus that we have authorized for use in connection with this offering. If any of these risks actually occurs, our business, financial condition, results of operations or cash flow could be seriously harmed. This could cause the trading price of our common stock to decline, resulting in a loss of all or part of your investment.

Our business, financial condition or results of operations could be materially adversely affected by any of these risks. The trading price of our securities could decline due to any of these risks, and you may lose part or all of your investment. This prospectus and the incorporated documents also contain forward-looking statements that involve risks and uncertainties. Our actual results could differ materially from those anticipated in these forward-looking statements as a result of certain factors, including the risks mentioned below. Forward-looking statements included in this prospectus are based on information available to us on the date hereof, and all forward-looking statements in documents incorporated by reference are based on information available to us as of the dates of such documents. We disclaim any intent to update any forward-looking statements.

Risks Related to this Offering

Resales of our common stock in the public market during this offering by our stockholders may cause the market price of our common stock to fall.

We may issue common stock from time to time in connection with this offering. The issuance from time to time of these new shares of our common stock, or our ability to issue these shares of common stock in this offering, could result in resales of our common stock by our current stockholders concerned about the potential dilution of their holdings. In turn, these resales could have the effect of depressing the market price for our common stock.

S - 7

Table of Contents

·anticipated results of financing activities;

·anticipated agreements with marketing partners;

·anticipated clinical study timelines or results;

·anticipated research and product development results;

·projected regulatory timelines;

·descriptions of plans or objectives of management for future operations, products or services;

·forecasts of future economic performance; and

·descriptions or assumptions underlying or relating to any of the above items.

Please also see the discussion of risks and uncertainties under the heading “Risk Factors” beginning on page S-7.

In light of these assumptions, risks and uncertainties, the results and events discussed in the forward-looking statements contained in this prospectus or in any document incorporated by reference might not occur. Investors are cautioned not to place undue reliance on the forward-looking statements, which speak only as of the date of this prospectus or the date of the document incorporated by reference in this prospectus. We are not under any obligation, and we expressly disclaim any obligation, to update or alter any forward-looking statements, whether as a result of new information, future events or otherwise. All subsequent forward-looking statements attributable to Sunshine Heart or to any person acting on its behalf are expressly qualified in their entireties by the cautionary statements contained or referred to in this section.

DESCRIPTION OF COMMON STOCK

The following description of our common stock is a summary only and is qualified in its entirety by reference to our certificate of incorporation and bylaws, both of which are exhibits to the registration statement of which this prospectus is a part, have been filed with the SEC and are available at the SEC’s website at www.sec.gov.

General Terms

We have authority to issue up to 100,000,000 shares of common stock, par value $0.0001 per share. As of March 18, 2014, we had 16,872,698 shares of our common stock outstanding.  All outstanding shares of our common stock are fully paid and non-assessable.

The transfer agent and registrar for transfers of shares of our common stock is American Stock Transfer & Trust Company, LLC.

The rights, preferences and privileges of the holders of our common stock are subject to, and may be adversely affected by, the rights of the holders of shares of any series of preferred stock that we may designate and issue in the future.  Subject in all cases to the foregoing limitation, the holders of our common stock have the rights, preferences and privileges below.

Dividends

Holders of our common stock are entitled to receive dividends when and as declared by our board of directors out of funds legally available.

S - 9

Table of Contents

Voting

Holders of our common stock are entitled to one vote for each share on each matter properly submitted to our stockholders for their vote; provided however, that except as otherwise required by law, holders of our common stock will not be entitled to vote on any amendment to our certificate of incorporation (including any certificate of designation filed with respect to any series of preferred stock) that relates solely to the terms of a series of outstanding preferred stock if the holders of such affected series are entitled, either separately or together as a class with the holders of one or more other such series, to vote thereon by law or pursuant to our certificate of incorporation (including any certificate of designation filed with respect to any series of preferred stock).

Subject to the voting restrictions described above, holders of our common stock may adopt, amend or repeal our bylaws and/or alter certain provisions of our certificate of incorporation with the affirmative vote of the holders of at least 66 2/3% of the voting power of all of the then-outstanding shares of our capital stock entitled to vote generally in the election of directors, voting together as a single class, in addition to any vote of the holders of a class or series of our stock required by law or our certificate of incorporation. Those provisions of our certificate of incorporation that may be altered only by the super-majority vote described above relate to:

·the number of directors on our board of directors, the classification of our board of directors and the terms of the members of our board of directors;

·the limitations on removal of any of our directors described below under “—Anti-Takeover Effects of Certain Provisions of Our Certificate of Incorporation and Bylaws, Our Stockholder Rights Plan, and Delaware Law;”

·the ability of our directors to fill any vacancy on our board of directors by the affirmative vote of a majority of the directors then in office under certain circumstances;

·the ability of our board of directors to adopt, amend or repeal our bylaws and the super-majority vote of our stockholders required to adopt, amend or repeal our bylaws described above;

·the limitation on action of our stockholders by written action described below under “—Anti-Takeover Effects of Certain Provisions of Our Certificate of Incorporation and Bylaws, Our Stockholder Rights Plan, and Delaware Law;”

·the choice of forum provision described below under “—Choice of Forum;”

·the limitations on director liability and indemnification described below under the heading “—Limitation on Liability of Directors and Indemnification;” and

·the super-majority voting requirement to amend our certificate of incorporation described above.

Conversion, Redemption and Preemptive Rights

Holders of our common stock do not have any conversion, redemption or preemptive rights pursuant to our organizational documents.

Liquidation, Dissolution and Winding-up

In the event of our liquidation, dissolution or winding up, holders of our common stock are entitled to share ratably in any assets remaining after the satisfaction in full of the prior rights of creditors and the aggregate of any liquidation preference pursuant to the terms of any certificate of designation filed with respect to any series of preferred stock.

S - 10

Table of Contents

Anti-Takeover Effects of Certain Provisions of Our Certificate of Incorporation and Bylaws, Our Stockholder Rights Plan, and Delaware Law

Certificate of Incorporation and Bylaws

Certain provisions of our certificate of incorporation and bylaws may be considered to have an anti-takeover effect, such as those provisions:

·providing for our board of directors to be divided into three classes with staggered three-year terms, with only one class of directors being elected at each annual meeting of our stockholders and the other classes continuing for the remainder of their respective three-year terms;

·authorizing our board of directors to issue from time to time any series of preferred stock and fix the voting powers, designation, powers, preferences and rights of the shares of such series of preferred stock;

·prohibiting stockholders from acting by written consent in lieu of a meeting;

·requiring advance notice of stockholder intention to put forth director nominees or bring up other business at a stockholders’ meeting;

·prohibiting stockholders from calling a special meeting of stockholders;

·requiring a 66 2/3% super-majority stockholder approval in order for stockholders to alter, amend or repeal certain provisions of our certificate of incorporation;

·requiring a 66 2/3% super-majority stockholder approval in order for stockholders to adopt, amend or repeal our bylaws;

·providing that, subject to the rights of the holders of any series of preferred stock to elect additional directors under specified circumstances, neither the board of directors nor any individual director may be removed without cause;

·creating the possibility that our board of directors could prevent a coercive takeover of our Company due to the significant amount of authorized, but unissued shares of our common stock and preferred stock;

·providing that, subject to the rights of the holders of any series of preferred stock, the number of directors shall be fixed from time to time exclusively by our board of directors pursuant to a resolution adopted by a majority of the total number of authorized directors; and

·providing that any vacancies on our board of directors under certain circumstances will be filled only by a majority of our board of directors then in office, even if less than a quorum, and not by the stockholders.

Stockholder Rights Plan

On June 14, 2013, the Company adopted a stockholder rights plan (the “Rights Plan”), which entitles the holders of the rights to purchase from the Company 1/1,000th of a share of Series A Junior Participating Preferred Stock, par value $0.0001 per share, at a purchase price of $35.00 per share, as adjusted (a “Right”), upon certain trigger events.  In connection therewith, on June 14, 2013, the Company’s board of directors authorized 30,000 shares of Series A Junior Participating Preferred Stock and it declared a dividend of one Right per each share of common stock of the Company outstanding as of June 24, 2013.  Each 1/1,000th of a share of Series A Junior Participating Preferred Stock has terms that are substantially the economic and voting equivalent of one share of the Company’s common stock.  However, until a Right is exercised or exchanged in accordance with the provisions of

S - 11

Table of Contents

the Rights Plan, the holder thereof will have no rights as a stockholder of the Company, including, but not limited to, the right to vote for the election of directors or upon any matter submitted to stockholders of the Company.  The Rights Plan has a three-year term and the board of directors may terminate the Rights Plan at any time (subject to the redemption of the Rights for a nominal value).  The Rights may cause substantial dilution to a person or group (together with all affiliates and associates of such person or group and any person or group of persons acting in concert therewith) that acquires beneficial ownership of 15% or more of the Company’s stock on terms not approved by the board of directors or takes other specified actions.

Delaware Law

We are also subject to Section 203 of the Delaware General Corporation Law, as amended (the “DGCL”), which generally prohibits a Delaware corporation from engaging in any business combination with any interested stockholder for a period of three years following the date that the stockholder became an interested stockholder, unless:

·prior to that date, our board of directors approved either the business combination or the transaction that resulted in the stockholder becoming an interested stockholder;

·upon consummation of the transaction that resulted in the stockholder becoming an interested stockholder, the interested stockholder owned at least 85% of our voting stock outstanding at the time the transaction commenced, excluding for purposes of determining the number of shares outstanding (but not the outstanding voting stock owned by the interested stockholder) those shares owned by (i) persons who are directors and also officers and (ii) employee stock plans in which employee participants do not have the right to determine confidentially whether shares held subject to the plan will be tendered in a tender or exchange offer; or

·on or subsequent to that date, the business combination is approved by our board of directors and authorized at an annual or special meeting of stockholders, and not by written consent, by the affirmative vote of at least 66  2/3% of the outstanding voting stock that is not owned by the interested stockholder.

In general, Section 203 of the DGCL defines an interested stockholder as an entity or person beneficially owning 15% or more of the outstanding voting stock of the corporation and any entity or person affiliated with or controlling or controlled by any of these entities or persons.

The above-summarized provisions of our certificate of incorporation and bylaws, the Rights Plan and the above-summarized provisions of the DGCL could make it more difficult to acquire us by means of a tender offer, a proxy contest or otherwise, or to remove incumbent officers and directors. These provisions are expected to discourage certain types of coercive takeover practices and takeover bids that our board of directors may consider inadequate and to encourage persons seeking to acquire control of us to first negotiate with our board of directors. We believe that the benefits of increased protection of our ability to negotiate with the proponent of an unfriendly or unsolicited proposal to acquire or restructure us outweigh the disadvantages of discouraging takeover or acquisition proposals because, among other things, negotiation of these proposals could result in an improvement of their terms.

Choice of Forum

Our certificate of incorporation provides that, unless we consent in writing otherwise, the Court of Chancery of the State of Delaware will be the sole and exclusive forum for any (i) derivative action or proceeding brought on our behalf; (ii) action asserting a breach of fiduciary duty owed by any of our directors, officers or other employees to us or any of our stockholders; (iii) action asserting a claim pursuant to the DGCL; or (iv) action asserting a claim that is governed by the internal affairs doctrine.

S - 12

Table of Contents

Limitation on Liability of Directors and Indemnification

Our certificate of incorporation limits the liability of our directors to the fullest extent permitted by Delaware law. Delaware law provides that directors of a corporation will not be personally liable for monetary damages for breach of their fiduciary duties as directors, except for liability for any:

·breach of their duty of loyalty to us or our stockholders;

·act or omission not in good faith or that involves intentional misconduct or a knowing violation of law;

·unlawful payment of dividends or redemption of shares as provided in Section 174 of the DGCL; or

·transaction from which the directors derived an improper personal benefit.

These limitations of liability do not apply to liabilities arising under federal securities laws and do not affect the availability of equitable remedies such as injunctive relief or rescission.

Our bylaws provide that we will indemnify and advance expenses to our directors and officers to the fullest extent permitted by law or, if applicable, pursuant to indemnification agreements. They further provide that we may choose to indemnify our other employees or agents from time to time. Subject to certain exceptions and procedures, our bylaws also require us to advance to any person who was or is a party, or is threatened to be made a party, to any proceeding by reason of the person’s service as one of our directors or officers all expenses incurred by the person in connection with such proceeding.

Section 145(g) of the DGCL and our bylaws also permit us to secure insurance on behalf of any officer, director, employee or other agent for any liability arising out of his or her actions in connection with their services to us, regardless of whether our bylaws permit indemnification. We maintain a directors’ and officers’ liability insurance policy.

We entered into indemnification agreements with each of our directors and executive officers that provide, in general, that we will indemnify them to the fullest extent permitted by law in connection with their service to us or on our behalf and, subject to certain exceptions and procedures, that we will advance to them all expenses that they incur in connection with any proceeding to which they are, or are threatened to be made, a party.

At present, there is no pending litigation or proceeding involving any of our directors or officers as to which indemnification is required or permitted, and we are not aware of any threatened litigation or proceeding that may result in a claim for indemnification.

Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers and controlling persons of the Company pursuant to the foregoing provisions, or otherwise, the Company has been advised that in the opinion of the SEC this indemnification is against public policy as expressed in the Securities Act and is therefore unenforceable.

Listing

Our common stock is listed on NASDAQ under the symbol “SSH.” CDIs representing beneficial ownership of our common stock traded on the ASX from September 2004 until the Company’s delisting from the ASX, which occurred at the close of trading on May 6, 2013.

USE OF PROCEEDS

We will retain broad discretion over the use of the net proceeds from our sale of securities offered hereby. Except as described in any prospectus supplement, we currently anticipate using the net proceeds from our sale of securities offered hereby primarily for general corporate purposes, including the further development, manufacture and commercialization of our C-Pulse System and for other working capital expenditures.

S - 13

Table of Contents

and incorporated herein by reference.  Such consolidated financial statements are incorporated herein by reference in reliance upon such report given on the authority of such firm as experts in accounting and auditing.

INCORPORATION BY REFERENCE

We “incorporate by reference” certain documents that we have filed with the SEC into this prospectus, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is deemed to be part of this prospectus, except for any information superseded by information contained directly in this prospectus. This prospectus incorporates by reference our:

·Annual Report on Form 10-K for the year ended December 31, 2013 filed with the SEC on March 14, 2014;

·the information specifically incorporated by reference into our Annual Report on Form 10-K for the year ended December 31, 2013 from our definitive Proxy Statement for the Annual Meeting of Stockholders to be held on May 29, 2014, to be filed with the SEC within 120 days after the end of the fiscal year covered by the Annual Report on Form 10-K for the year ended December 31, 2013;

·the description of our common stock in our registration statement on Form 10 filed with the SEC on September 30, 2011, including any amendment or reports filed for the purpose of updating such description; and

·the description of our Series A Junior Participating Preferred Stock, par value $0.0001 per share, in our registration statement on Form 8-A filed with the SEC on June 14, 2013.

All documents we file with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act, except as to any portion of any report or document that is not deemed filed under such provisions, on or after the date of filing of the registration statement containing this prospectus until the earlier of the date on which all of the securities registered hereunder have been sold or the registration statement of which this prospectus is a part has been withdrawn, shall be deemed incorporated by reference in this prospectus and to be a part of this prospectus from the date of filing of those documents.  Nothing in this prospectus shall be deemed to incorporate information furnished but not filed with the SEC pursuant to Item 2.02 or 7.01 of Form 8-K.

These documents may also be accessed on our website at www.sunshineheart.com. Information contained in, or accessible through, our website is not a part of this prospectus.

You may obtain documents incorporated by reference into this prospectus at no cost by writing or telephoning us at the following address:

Sunshine Heart, Inc.

Attention: David A. Rosa, Chief Executive Officer

12988 Valley View Road

Eden Prairie, MN 55344

Tel: (952) 345-4200

Any statements contained in a document incorporated by reference in this prospectus shall be deemed to be modified or superseded for purposes of this prospectus to the extent that a statement contained in this prospectus (or in any other subsequently filed document which also is incorporated by reference in this prospectus) modifies or supersedes such statement. Any statement so modified or superseded shall not be deemed to constitute a part of this prospectus except as so modified or superseded.

S - 16

Table of Contents

PART II. II

INFORMATION NOT REQUIRED IN PROSPECTUS

ITEM 14.Other Expenses of Issuance and Distribution.

The following table sets forth various expenses in connection with the sale and distribution of the securities being registered.  All of the amounts shown are estimates except for the Securities and Exchange Commission Registration Fee.

(1)These fees will be dependent on the type of securities offered and number of offerings and, therefore, cannot be estimated at this time. In accordance with Rule 430B, additional information regarding estimated fees and expenses will be provided at the time information as to an offering is included in a prospectus supplement.

ITEM 15.Indemnification of Directors and Officers.

Our certificate of incorporation and bylaws provide that each person who was or is made a party or is threatened to be made a party to or is otherwise involved (including, without limitation, as a witness) in any action, suit or proceeding, whether civil, criminal, administrative or investigative, by reason of the fact that he or she is or was a director or an officer of Sunshine Heart, Inc. or is or was serving at our request as a director, officer, or trustee of another corporation, or of a partnership, joint venture, trust or other enterprise, including service with respect to an employee benefit plan, whether the basis of such proceeding is alleged action in an official capacity as a director, officer or trustee or in any other capacity while serving as a director, officer or trustee, shall be indemnified and held harmless by us to the fullest extent authorized by the Delaware General Corporation Law, as amended (the “DGCL”), against all expense, liability and loss (including attorneys’ fees, judgments, fines, ERISA excise taxes or penalties and amounts paid in settlement) reasonably incurred or suffered by such.

Section 145 of the DGCL permits a corporation to indemnify any director or officer of the corporation against expenses (including attorney’s fees), judgments, fines and amounts paid in settlement actually and reasonably incurred in connection with any action, suit or proceeding brought by reason of the fact that such person is or was a director or officer of the corporation, if such person acted in good faith and in a manner that he or she reasonably believed to be in, or not opposed to, the best interests of the corporation, and, with respect to any criminal action or proceeding, if he or she had no reason to believe his or her conduct was unlawful. In a derivative action, (i.e., one brought by or on behalf of the corporation), indemnification may be provided only for expenses actually and reasonably incurred by any director or officer in connection with the defense or settlement of such an action or suit if such person acted in good faith and in a manner that he or she reasonably believed to be in, or not opposed to, the best interests of the corporation, except that no indemnification shall be provided if such person shall have been adjudged to be liable to the corporation, unless and only to the extent that the court in which the action or suit was brought shall determine that the defendant is fairly and reasonably entitled to indemnity for such expenses despite such adjudication of liability.

34

Table of Contents

We carry insurance policies insuring our directors and officers against certain liabilities that they may incur in their capacities as directors and officers.

The Company has entered into indemnification agreements with each of its directors and executive officers. Pursuant to the indemnification agreements, the Company agrees to hold harmless and indemnify its directors and executive officers to the fullest extent authorized or permitted by the provisions of the Company’s certificate of incorporation and bylaws and the DGCL, including for any amounts that such director or officer becomes obligated to pay because of any claim to which such director or officer is made or threatened to be made a party, witness or participant, by reason of such director’s or officer’s service as a director, officer, employee or other agent of the Company.

There are certain exceptions from the Company’s obligation to indemnify its directors and executive officers pursuant to the indemnification agreements, including for “short-swing” profit claims under Section 16(b) of the Securities Exchange Act of 1934, as amended, losses that are as a result offrom conduct that is established by a final judgment as knowingly fraudulent or deliberately dishonest or that constituted willful misconduct, or that constituted a breach of the duty of loyalty to the Company or resulted in any improper personal profit or advantage, where payment is actually made to a director or officer under an insurance policy, indemnity clause, bylaw or agreement, except in respect of any excess beyond payment under such insurance, clause, bylaw or agreement, for indemnification which is not lawful, or in connection with any proceeding initiated by such director or officer, or any proceeding against the Company or its directors, officers, employees or other agents, unless (i) such indemnification is expressly required to be made by law, (ii) the proceeding was authorized by the board of directors of the Company, (iii) such indemnification is provided by the Company, in its sole discretion, pursuant to the powers vested in the Company under the DGCL, or (iv) the proceeding is initiated to enforce a claim for indemnification pursuant to the indemnification agreement.

All agreements and obligations of the Company contained in the indemnification agreements shall continue during the period when the director or officer who is a party to an indemnification agreement is a director, officer, employee or other agent of the Company (or is or is serving at the request of the Company as a director, officer, employee or other agent of another corporation, partnership, joint venture, trust, employee benefit plan or other enterprise) and shall continue thereafter so long as such director or officer shall be subject to any possible claim or threatened, pending or completed action, suit or proceeding, whether civil, criminal, arbitrational, administrative or investigative. In addition, the indemnification agreements provide for partial indemnification and advance of expenses.

Insofar as indemnification for liabilities arising under the Securities Act of 1933 as amended, may be permitted to our directors, officers or controlling persons pursuant to the foregoing provisions, or otherwise, we have been advised that in the opinion of the Securities and Exchange Commission this

35

Table of Contents

II - 3

Table of Contents