Exhibit 23.1 INDEPENDENT AUDITORS' CONSENT We consent to the incorporation by reference in this Post-Effective Amendment No. 1 to the Registration Statement of Thoratec Corporation on Form S-8 of our report dated February 21, 2002 (March 11, 2002 as to Note 7), appearing in the Annual Report on Form 10-K of Thoratec Corporation for the year ended December 29, 2001. /s/ Deloitte & Touche, LLP San Francisco, California July 1, 2002