Heartware International (HTWR) 8-K Entry into a Material Definitive Agreement

Exhibit 99.1

HeartWare International, Inc.
Announces Concurrent Public Offerings of
Convertible Senior Notes
and Common Stock

(FRAMINGHAM, Mass. and SYDNEY) December 9, 2010—HeartWare International, Inc. (NASDAQ: HTWR, ASX: HIN) (“HeartWare”) announced today its intention to offer, subject to market and other conditions, $100 million principal amount of convertible senior notes due 2017 (the “notes”) pursuant to an effective shelf registration statement filed with the Securities and Exchange Commission (“SEC”) today. HeartWare also intends to grant the underwriters an option to purchase up to an additional $15 million principal amount of notes to cover over-allotments, if any.

Concurrently with the notes offering, Apple Tree Partners I, L.P., one of HeartWare’s existing stockholders, intends to offer, subject to market and other conditions, 1,000,000 shares of HeartWare’s common stock pursuant to an effective shelf registration statement filed with the SEC today. Apple Tree Partners I, L.P. will also grant the underwriters an option to purchase up to 150,000 additional shares to cover over-allotments, if any. The completion of the common stock offering is not contingent upon the completion of the notes offering and the notes offering is not contingent upon the completion of the common stock offering.

HeartWare intends to use the net proceeds from the notes offering for general corporate and working capital purposes, including, but not limited to, expansion of its manufacturing capabilities and/or licensing of or investment in complementary products, technologies or businesses. HeartWare will not receive any of the proceeds from the common stock offering.

J.P. Morgan Securities LLC is acting as the sole book-running manager for both the convertible notes and common stock offerings.

This press release shall not constitute an offer to sell or a solicitation of an offer to buy any securities nor shall there be any sale of these securities in any state in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of such state. The issuer has filed a registration statement (including a prospectus) with the SEC for the offerings to which this communication relates. Each offering of securities will be made only by means of a prospectus and the related prospectus supplement. Before you invest, you should read the prospectus and the related prospectus supplement and any other document HeartWare has filed with the SEC for more complete information about HeartWare and the respective offering. You may get these documents for free by visiting EDGAR on the SEC Website atwww.sec.gov. Alternatively, copies of the prospectus and the related prospectus supplement can be obtained by contacting J.P. Morgan Securities LLC, c/o Broadridge Financial Solutions, 1155 Long Island Avenue, Edgewood, New York 11717 or by calling 1-866-803-9204.

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About HeartWare International

HeartWare International develops and manufactures miniaturized implantable heart pumps, or ventricular assist devices, to treat patients suffering from advanced heart failure.

Forward-Looking Statements

This announcement contains forward-looking statements that are based on management’s beliefs, assumptions and expectations and on information currently available to management. All statements that address operating performance, events or developments that we expect or anticipate will occur in the future are forward-looking statements, including without limitation our expectations with respect to regulatory submissions and approvals such as FDA approval of our expected premarket approval application for our HeartWare^® Ventricular Assist System for a bridge-to-transplant indication; our expectations with respect to our clinical trials, including enrollment in or completion of our clinical trials; our expectations with respect to the integrity or capabilities of our intellectual property position; our ability to commercialize our existing products; our ability to develop and commercialize new products; and our estimates regarding our capital requirements and financial performance, including profitability. Management believes that these forward-looking statements are reasonable as and when made. You should not place undue reliance on forward-looking statements because they speak only as of the date when made. HeartWare does not assume any obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events or otherwise. HeartWare may not actually achieve the plans, projections or expectations disclosed in forward-looking statements, and actual results, developments or events could differ materially from those disclosed in the forward-looking statements. Forward-looking statements are subject to a number of risks and uncertainties, including without limitation, the possibility the FDA does not approve the marketing of the HeartWare^® Ventricular Assist System in the U.S., and those described in “Part I, Item 1A. Risk Factors” in our Annual Report on Form 10-K filed with the Securities and Exchange Commission. We may update our risk factors from time to time in “Part II, Item 1A. Risk Factors” in our Quarterly Reports on Form 10-Q, or other current reports, as filed with the SEC.

For further information:
Christopher Taylor
HeartWare International, Inc.
Email: ctaylor@heartwareinc.com
Phone: +1 508 739 0864

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