WORLD HEART CORPORATION WORLD HEART INC. 8% SECURED CONVERTIBLE PROMISSORY NOTE

Exhibit 10.2

NEITHER THIS NOTE NOR THE SECURITIES ISSUABLE UPON CONVERSION OR EXERCISE OF THESE SECURITIES HAVE BEEN REGISTERED WITH THE SECURITIES AND EXCHANGE COMMISSION OR THE SECURITIES COMMISSION OF ANY STATE IN RELIANCE UPON AN EXEMPTION FROM REGISTRATION UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”), AND, ACCORDINGLY, MAY NOT BE OFFERED OR SOLD EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT OR PURSUANT TO AN AVAILABLE EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO, THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT AND IN ACCORDANCE WITH APPLICABLE STATE SECURITIES LAWS AS EVIDENCED BY A LEGAL OPINION OF COUNSEL TO THE TRANSFEROR TO SUCH EFFECT, THE SUBSTANCE OF WHICH SHALL BE REASONABLY ACCEPTABLE TO THE BORROWERS.

UNLESS PERMITTED UNDER CANADIAN SECURITIES LEGISLATION, THE HOLDER OF THIS SECURITY MUST NOT TRADE THE SECURITY BEFORE APRIL 12, 2008.

WORLD HEART CORPORATION

WORLD HEART INC.

8% SECURED CONVERTIBLE PROMISSORY NOTE

FOR VALUE RECEIVED, World Heart Corporation , a Canadian corporation (the “ Company ”), and World Heart Inc. , a Delaware corporation and wholly-owned subsidiary of the Company (“ WHI ”), as co-borrowers (each referred to herein as a “ Borrower ” and together the “ Borrowers ”), jointly and severally, promise to pay to the order of ABIOMED, Inc. , a Delaware corporation, or its registered assigns (the “ Investor ”), the principal amount outstanding on this note from time to time, up to a maximum principal amount of $5,000,000, on the earliest of (a) the date on or after the Maturity Date (as defined below) on which demand for payment is made by the Investor; (b) the date on which this 8% Secured Convertible Promissory Note (this “ Note ”) is required to be repaid as provided hereunder; or (c) the Final Maturity Date (as defined below) (such earliest date of payment, the “ Required Payment Date ”), and to pay interest to the Investor on the principal amount of this Note outstanding from time to time in accordance with the provisions hereof. The principal amount outstanding under this Note on the date hereof is $1,000,000 and upon the Second Closing, (as defined in the Purchase Agreement (as defined below)) an additional $4,000,000 of principal shall be advanced by Investor to Borrowers. In the event that the Second Closing does not occur for any reason, for all purposes of this Note, including without limitation the conversion provisions, the principal amount of the Note shall be no greater than $1,000,000. Any amounts on this Note which are not paid when

due shall bear interest at the rate equal to the lower of 15% per annum and the maximum lawful rate authorized under applicable law (the “ Maximum Rate ”) from the due date thereof until the same is paid. This Note is subject to the following additional provisions:

1. Definitions . In addition to the terms defined elsewhere in this Note: (a) capitalized terms that are used but not otherwise defined herein have the meanings given to such terms in the Note Purchase Agreement, dated as of December 11, 2007, among the Company, WHI and the Investor (as amended, supplemented or otherwise modified from time to time, the “Purchase Agreement ”), and (b) the following terms have the meanings indicated below:

“ Adjusted Conversion Price ” shall have the meaning set forth in Section 9(d).

“ Bankruptcy Event ” means any of the following events: (a) the Company or any Subsidiary commences a case or other proceeding under any bankruptcy, reorganization, arrangement, adjustment of debt, relief of debtors, dissolution, insolvency or liquidation or similar law of any jurisdiction relating to the Company or any Subsidiary thereof; (b) there is commenced against the Company or any Subsidiary any such case or proceeding that is not dismissed within 75 days after commencement; (c) the Company or any Subsidiary is adjudicated by a court of competent jurisdiction insolvent or bankrupt or any order of relief or other order approving any such case or proceeding is entered; (d) the Company or any Subsidiary suffers any appointment of any custodian or the like for it or any substantial part of its property that is not discharged or stayed within 75 days; (e) under applicable law the Company or any Subsidiary makes a general assignment for the benefit of creditors; (f) the Company or any Subsidiary fails to pay, states that it is unable to pay or is unable to pay, its debts generally as they become due; or (g) the Company or any Subsidiary, by any act or failure to act, expressly indicates its consent to, approval of or acquiescence in any of the foregoing or takes any corporate or other action for the purpose of effecting any of the foregoing.

“ Change of Control ” means the occurrence of any of the following in one or a series of related transactions: (i) any transaction or series of related transactions to which the Company is party (including, without limitation, any stock acquisition, recapitalization, reorganization, share exchange, merger or consolidation) resulting in the holders of the voting securities of the Company outstanding immediately prior thereto, as a result of shares of the Company held by such holders prior thereto, holding less than fifty percent (50%) of the total voting power represented by the voting securities of the surviving entity outstanding immediately after such transaction or series of transactions, other than any stock sale or convertible debt issuance for capital raising purposes so long as (a) no single investor or group of affiliated investors, except for Special Situations Funds, gains control of fifty percent (50%) or more of the total voting power of the Company as a result of such financing and (b) none of the following competitors of Abiomed (Thoratec Corporation, Levatronix, Datascope, Arrow International, CardiacAssist, Inc., JarvikHeart, Syncardia Systems, MicroMed Technology and Ventracor), together with any affiliates, gains control of more than 20% of the Company or the surviving corporation as a result of such financing (a “ Sale Transaction ”), (ii) a Fundamental Transaction (as defined in Section 9(c)); (iii) the sale, without the consent of Investor, of all or a material portion of the Company’s or any Subsidiary’s assets in one or a series of related transactions, including, without limitation, the sale of any of the following product lines: Novacor I, Novacor II, Levacor and MiVAD (an “ Asset Sale Transaction ”); (iv) any transaction resulting in the Company

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owning less than 100% of the outstanding equity of WHI (a “ WHI Sale ”); (v) consummation of a “Rule 13e-3 transaction” as defined in Rule 13e-3 under the Exchange Act with respect to the Company, or (vi) the execution by the Company or its controlling shareholders of an agreement providing for or reasonably likely to result in any of the foregoing events. Notwithstanding anything to the contrary in any of the Transaction Documents, neither the Reincorporation Plan, nor a Monetization Plan approved by the Investor pursuant to the Purchase Agreement, shall be considered to be a “Change of Control,” “Sale Transaction”, “Asset Sale Transaction”, or “WHI Sale”.

“ Closing Price ” means, for any date, the price determined by the first of the following clauses that applies: (a) if the Common Stock is then listed or quoted on an Eligible Market, the closing bid price per share of the Common Stock for such date (or the nearest preceding date if no trading on such date) on the primary Eligible Market or exchange on which the Common Stock is then listed or quoted (based on the Eligible Market with the highest trading volume); (b) if prices for the Common Stock are then quoted on the OTC Bulletin Board, the closing bid price per share of the Common Stock for such date (or the nearest preceding date if no trading on such date) so quoted; (c) if prices for the Common Stock are then reported in the “Pink Sheets” published by the National Quotation Bureau Incorporated (or a similar organization or agency succeeding to its functions of reporting prices), the most recent bid price per share of the Common Stock so reported; or (d) in all other cases, the fair market value of a share of Common Stock as determined by an independent qualified appraiser selected in good faith and paid for by the Investor.

“ Conversion Date ” means the date a Conversion Notice together with the Conversion Schedule is delivered to the Company in accordance with Section 4(a).

“ Conversion Notice ” means a written notice in the form attached hereto as Exhibit A .

“ Conversion Price ” means the lesser of the Initial Conversion Price or Adjusted Conversion Price.

“ dollars ” or “ $ ” shall mean lawful money of the United States.

“ Default ” means any event or condition which constitutes an Event of Default or that upon notice, lapse of time or both would, unless cured or waived, become an Event of Default.

“ Eligible Market ” means any of the New York Stock Exchange, the American Stock Exchange, the Nasdaq Capital Market, the Nasdaq Global Market, the Nasdaq Global Select Market or the OTC Bulletin Board.

“ Equity Conditions Are Satisfied ” means, as of any date of determination, that each of the following conditions is (or would be) satisfied on such date, if the Company were to issue on such date all of the Underlying Shares then issuable upon conversion in full of the outstanding principal amount of this Note and all accrued and unpaid interest under this Note, assuming Investor elects to convert all interest pursuant to Section 2(b): (i) the number of authorized but unissued and otherwise unreserved shares of Common Stock is sufficient for such issuance, (ii) the Common Stock is listed or quoted (and is not suspended from trading) on an Eligible Market and such shares of Common Stock are approved for listing on such Eligible Market upon

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issuance, (iii) such Common Stock is registered for resale under the Registration Statement and the prospectus under such Registration Statement is available for the sale of all Registrable Securities held by the Investor or all of the Underlying Shares are eligible for resale pursuant to Rule 144 without time or volume limitations, or (iv) no public announcement by the Company of a pending or proposed Change of Control transaction has occurred that has not been consummated.

“ Event of Default ” means any one of the following events (whatever the reason and whether it shall be voluntary or involuntary or effected by operation of law or pursuant to any judgment, decree or order of any court, or any order, rule or regulation of any administrative or governmental body):

(i) any default in the payment (free of any claim of subordination), when the same becomes due and payable (whether on the Payment Date, the Required Payment Date or by acceleration or otherwise), of principal or interest in respect of this Note within 5 Trading Days of demand by the Investor;

(ii) the Company or any Subsidiary (1) fails to pay when due any monetary obligation (regardless of amount) to any third party under any currently existing or hereafter arising debenture or any mortgage, credit agreement or other facility, indenture agreement, factoring agreement or other instrument under which there may be issued, or by which there may be secured or evidenced, any Debt or under any long term leasing or factoring arrangement, if the aggregate amount of the obligations and liabilities of the Company and the Subsidiaries thereunder exceed $100,000 (each of the foregoing a “ Material Debt Agreement ”), or (2) fails to observe or perform any other material obligation under any Material Debt Agreement, and such failure results in the obligations thereunder becoming or being declared due and payable prior to the date on which they would otherwise become due and payable;

(iii) either Borrower (a) shall fail to observe or perform any material covenant, condition or agreement contained in any Loan Document (other than the Registration Rights Agreement and those specified in clause (i) above or clause (v), (vii), (viii), (ix), (x) or (xi) below), and (b) such failure shall to continue unremedied for a period of twenty Trading Days after the date on which written notice of such default is first given to the Borrowers by the Investor (it being understood that no prior notice need be given in the case of a default that cannot reasonably be cured within seven Trading Days);

(iv) either Borrower’s representations and warranties set forth in the Purchase Agreement shall be incorrect in any material respect as of the Original Issue Date;

(v) the occurrence of a Bankruptcy Event;

(vi) any Loan Document shall cease, for any reason, except as provided therein, to be in full force and effect in all material respects;

(vii) either Borrower shall assert in writing that any Loan Document has ceased, for any reason, to be in full force and effect or shall disavow any of its obligations thereunder;

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(viii) the Common Stock shall not be listed or quoted, or is suspended from trading, on an Eligible Market for a period of three Trading Days within a one year period (which need not be consecutive Trading Days);

(ix) the Company fails to deliver a stock certificate evidencing Underlying Shares to an Investor within five Trading Days after a Conversion Date or in the case of exercises under the Warrant, within five Trading Days after the date the Warrant is exercised, or the conversion or exercise rights of the Investor pursuant to the terms hereof or the terms of the Warrant is otherwise suspended for any reason (other than as a result of the limitations set forth in Section 4(b) hereof or the limitations set forth in the Warrant, respectively, and except as a result of the effects of Section 7.5(b) of the Purchase Agreement);

(x) the Company fails to have available a sufficient number of authorized but unissued and otherwise unreserved shares of Common Stock available to issue the Underlying Shares upon any conversion of this Note or upon any exercise of the Warrant; or

(xi) either Borrower effects or publicly announces its intention to effect a Sale Transaction, an Asset Sale Transaction, or a WHI Sale.

“ Final Maturity Date ” means December 11, 2017.

“ Initial Conversion Price ” means $1.748948, subject to adjustment from time to time pursuant to Section 9.

“ Loan Documents ” means the Note, the Warrant, the Purchase Agreement, the Registration Rights Agreement and the Security Agreements.

“ Maturity Date ” means December 11, 2009.

“ Original Issue Date ” has the meaning set forth on the face of this Note.

“ Payment Date ” has the meaning set forth in Section 11 of this Note.

“ Payment Notice ” has the meaning set forth in Section 11 of this Note.

“ Special Situations Funds ” means the group consisting of Special Situations Cayman Fund, L.P., Special Situations Fund III, L.P., Special Situations Fund III QP, L.P., Special Situations Private Equity Fund, L.P. MGP Advisors Limited, AWM Investment Company, Inc., the Special Situations Technology Fund, L.P., the Special Situations Technology Fund II, L.P., the Special Situations Private Equity Fund, L.P. and the Special Situations Life Sciences Fund, L.P.

2. Interest . (a) The Borrowers shall pay interest to the Investor on the aggregate unconverted and then outstanding principal amount of this Note at the rate of 8% per annum. Such interest shall accrue from the Original Issue Date of this Note, but shall not become payable until the earlier of the Required Payment Date or the date that this Note has been paid or converted in full, at which time all interest then having accrued (including interest accrued on principal previously converted) shall become payable. Interest payments hereunder

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may be made in cash or, subject to the conditions of Section 2(b), in shares of Common Stock. Interest shall be calculated on the basis of a 360-day year for the actual number of days elapsed and shall accrue daily commencing on the Original Issue Date.

(b) Subject to the conditions and limitations set forth below, in lieu of paying interest in cash the Company shall, at the Investor’s option, convert accrued interest on this Note by delivering on the applicable payment date, a number of shares of Common Stock equal to the quotient obtained by dividing the amount of such interest by the average Closing Price for the ten Trading Days immediately preceding (but not including) the date Investor provides written notice of its election to convert accrued interest. The Investor must deliver written notice to the Company indicating the manner in which it intends to receive interest at least five (5) Trading Days prior to the applicable payment date. Failure to timely provide such written notice shall be deemed an irrevocable election by the Investor to receive such interest in cash. All interest payable in respect of this Note on the payment date must be paid in the same manner.

(c) Solely for purposes of the Interest Act (Canada), (i) as interest is to be computed or expressed at a rate (the “ Specified Rate ”) on the basis of a year of 360 days hereunder, the annual rate of interest to which the Specified Rate is equal is the Specified Rate multiplied by a fraction, the numerator of which is the actual number of days in the relevant year and the denominator of which is 360; (ii) the principle of deemed reinvestment of interest shall not apply to any interest calculation hereunder; and (iii) the rates of interest stipulated herein are intended to be nominal rates and not effective rates or yields.

3. Registration of Transfers and Exchanges . Subject to compliance with applicable federal, state, provincial and foreign securities laws, the Investor may transfer all or any portion of this Note and the Borrowers shall register the transfer of any portion of this Note upon surrender of this Note to the Borrowers at the address for notice set forth herein. Upon any such registration or transfer, a new Note, in substantially the form of this Note (any such new debenture, a “ New Note ”), evidencing the portion of this Note so transferred shall be issued to the transferee and a New Note evidencing the remaining portion of this Note not so transferred, if any, shall be issued to the transferring Investor. The acceptance of the New Note by the transferee thereof shall be deemed the acceptance by such transferee of all of the rights and obligations of a holder of a Note. The Borrowers agree that their prior consent is not required for the transfer of any portion of this Note; provided , however, that the Borrowers shall be entitled to reasonable assurance that such transfer complies with applicable federal, state and foreign securities laws. No service charge or other fee will be imposed in connection with any such registration of transfer or exchange.

4. Conversion .

(a) At the Option of the Investor . All or any portion of the principal amount of this Note then outstanding together with any accrued and unpaid interest hereunder shall be convertible into shares of Common Stock at the Conversion Price (subject to limitations set forth in Section 4(b)), at the option of the Investor, at any time and from time to time from and after the Original Issue Date. The Investor may effect conversions under this Section 4(a), by delivering to the Company a Conversion Notice together with a schedule in the form of Schedule

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1 attached hereto (the “ Conversion Schedule ”). If the Investor is converting less than all of the principal amount and accrued and unpaid interest represented by this Note, or if a conversion hereunder may not be effected in full due to the application of Section 4(b), the Company shall honor such conversion to the extent permissible hereunder and shall promptly deliver to the Investor a Conversion Schedule indicating the principal amount and accrued and unpaid interest which has not been converted.

(b) Certain Conversion Restrictions . Notwithstanding anything to the contrary contained herein, to the extent applicable, until such time as the issuance of shares of Common Stock under this Note and the Warrant have been approved by the Company’s stockholders in accordance with Nasdaq Marketplace Rule 4350(i) and any applicable Nasdaq Marketplace Rule, the number of shares of Common Stock that may be acquired by the Investor upon conversion of this Note (or otherwise in respect hereof) and upon exercise of the Warrant, together, shall be limited to no greater than 19.9% of the total number of shares of Common Stock outstanding on the Original Issue Date (the “Initial Cap”). For the avoidance of doubt, in implementing the foregoing restriction, the Investor shall be free to exercise the Warrant for the full amount of the Initial Cap to the extent that the Investor has not converted the Note into shares of Common Stock and any cash payments made to the Investor under this Note shall not be counted in any way towards the Initial Cap. Notwithstanding the foregoing, to the extent that the limitation set forth in this Section 4(b) prevents the issuance of shares on conversion, the Investor is nonetheless entitled to payment of any and all principal and interest provided for hereunder in accordance with the terms of this Note.

5. Mechanics of Conversion .

(a) The number of Underlying Shares issuable upon any conversion hereunder shall equal the outstanding principal amount of this Note to be converted, divided by the Conversion Price on the Conversion Date, plus (if indicated in the applicable Conversion Notice) the amount of any accrued but unpaid interest on this Note through the Conversion Date, divided by the Conversion Price on the Conversion Date.

(b) The Company shall, by the third Trading Day following each Conversion Date, issue or cause to be issued and cause to be delivered to or upon the written order of the Investor and in such name or names as the Investor may designate a certificate for the Underlying Shares issuable upon such conversion. The Investor, or any Person so designated by the Investor to receive Underlying Shares, shall be deemed to have become holder of record of such Underlying Shares as of such Conversion Date.

(c) The Investor shall not be required to deliver the original Note to the Company in order to effect a co