EMPLOYMENT AGREEMENT

Exhibit 10.18

[***] A CONFIDENTIAL PORTION OF THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

Cambridge Heart, Inc.

100 Ames Pond Road

Tewksbury, MA 01876

EMPLOYMENT AGREEMENT

Effective as of November 24, 2008

Roderick de Greef

c/o Cambridge Heart, Inc.

100 Ames Pond Road

Tewksbury, MA 01876

Dear Roderick:

You have agreed to serve as Chairman of the Board of Cambridge Heart, Inc. (the “Company”) commencing November 24, 2008 (the “Effective Date”), in accordance with the following terms of your employment by the Company. You are referred to herein as the “Executive”.

1. EMPLOYMENT AND TERM : Subject to the terms and conditions set forth in this Agreement, the Company hereby offers and the Executive hereby accepts employment. The term of this Agreement (the “Employment Period”) shall commence on the Effective Date and end on November 24, 2011, or the date on which your employment is sooner terminated as provided below. The Employment Period shall be automatically extended for successive periods of one year unless either party gives to the other written notice not less than thirty (30) days prior to the then-current expiration date that it or he does not wish to extend the term of this Agreement.

2. CAPACITY AND PERFORMANCE :

(a) During the Employment Period, the Executive will serve as the Company’s Chairman of the Board. During the Employment Period, the Executive shall devote approximately 50% of a regular work week and his best efforts, business judgment, skill and knowledge to the advancement of the business and interests of the Company and to the discharge of his duties and responsibilities hereunder. The Executive shall comply with all lawful written policies of the Company in effect from time to time. The Executive may engage in other business activities and may pursue personal interests (including, without limitation, industry civil and charitable activities), and attend to his personal investments, so long as such activities and interests do not interfere with or adversely affect the performance of his duties and responsibilities hereunder.

(b) Subject to the direction and control of the Board and any committee thereof, the Executive shall, together with the Chief Executive Officer and Board, formulate the strategic plan for the Company and, together with the Chief Executive Officer, oversee the execution of that corporate strategy. The Executive shall perform such other duties and responsibilities on behalf of the Company as may be designated from time to time by the Board, provided that such duties shall be reasonably consistent with those duties assigned to Chairmen of the Board in organizations comparable to the Company.

(c) On the Effective Date, the Executive shall be appointed a member of the Company’s Board of Directors and shall serve as a member of the Board without additional compensation. During the Employment Period, at each annual meeting of the Company’s stockholders at which the Executive’s membership on the Board has expired, the Company will nominate the Executive to serve as a member of the Board. Upon termination of the Executive’s employment with the Company for any reason, unless the Company’ s Board of Directors affirmatively requests that the Executive remain on the Board, the Executive will be deemed to have resigned from the Board voluntarily as of the last day of employment with the Company; and at the Board’s request, the Executive shall execute any documents necessary to reflect such resignation.

(d) The Executive hereby represents and warrants that the execution of this Agreement and the performance of his obligations hereunder will not breach or be in conflict with any other agreement to which the Executive is a party or is bound and that the Executive is not subject to any covenants against competition or similar covenants that would affect the performance of his obligations hereunder. The Executive will not disclose to or use any proprietary information of a third party without such party’s consent.

3. SALARY : The Company shall pay the Executive a base salary at the rate of One Hundred Twenty Thousand Dollars ($120,000) per annum, payable in accordance with the payroll practices of the Company for its executives. Such base salary, as from time to time increased by the Board in its sole discretion, is hereafter referred to as the “Base Salary.”

4. STOCK OPTIONS :

(a) Grant of Stock Option : The Executive shall receive a stock option (the “Stock Option”) to purchase Five Hundred Fifty Thousand (550,000) shares of common stock of the Company. The Stock Option shall be granted under, and shall be subject to the terms and conditions of, the Company’s 2001 Stock Incentive Plan (the “2001 Plan”) and shall otherwise contain such terms and conditions consistent with the terms and conditions of options regularly granted to senior executives of the Company. The Stock Option shall have an exercise price equal to the closing price for shares of common stock of the Company on the Effective Date and shall have a term of 10 years. The Executive will have the right to exercise the Stock Option for a period of 90 days after the termination of employment (but in no event after the expiration date of the Stock Option) to the extent that the Executive was entitled to exercise the Option on the date of such termination.

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(b) Vesting of Stock Option : The Stock Option shall become exercisable in three equal annual installments beginning on the first anniversary of the Effective Date (the “Annual Vesting Dates”) as follows: 183,333 on November 24, 2009, 183,333 on November 24, 2010, and 183,334 on November 24, 2011. Notwithstanding the foregoing, upon the occurrence of each of the following events (each, a “Performance-Based Acceleration Event”), the Stock Option shall immediately become exercisable with respect to the lesser of (i) the number of shares set forth opposite each Performance-Based Acceleration Event below and (ii) the positive difference between total number of shares under the Stock Option that are not yet exercisable and the number of shares set forth opposite the respective Performance-Based Acceleration Event below. The Performance-Based Acceleration Events are:

The shares underlying the Stock Option that become exercisable upon the occurrence of a Performance-Based Acceleration Event shall reduce the number of shares that otherwise would next become exercisable on an Annual Vesting Date following the date of the Performance-Based Acceleration Event. In no event shall the occurrence of a Performance-Based Acceleration Event cause the total number of shares covered by the Stock Option to exceed 550,000 shares.

5. VACATIONS : During the term of his employment, the Executive shall be entitled to two (2) weeks of vacation per annum, on terms as provided by the Company for its other senior executives, to be taken at such times and intervals as shall be determined by the Executive, subject to the reasonable business needs of the Company. Vacation time shall not cumulate from year to year.

6. BENEFITS : During the term of his employment and subject to any contribution therefor generally required of employees of the Company, the Executive shall be entitled to participate in any and all employee benefit plans from time to time in effect for part-time employees of the Company generally, except to the extent such plans are in a specific category of benefits otherwise provided to the Executive. Such participation shall be subject to (a) the terms of the applicable plan documents, (b) generally applicable Company policies and (c) the discretion of the Board or any administrative or other committee provided for in or contemplated by such plan. The Company may alter, modify, add to or delete its employee benefit plans at any time as it, in its sole judgment, determines to be appropriate, without recourse by the Executive. In the event that the Executive is not eligible to participate in the Company’s health insurance

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benefit plan, the Company shall reimburse the Executive for the cost to the Executive of maintaining his current family medical insurance coverage, provided that the aggregate amount of such reimbursement shall not exceed $2,000 per month. Reimbursement of the Executive’s family medical insurance coverage costs shall be subject to such reasonable substantiation and documentation as may be specified by the Company from time to time.

7. BUSINESS EXPENSES : The Company shall pay or reimburse the Executive for all reasonable and necessary business expenses incurred or paid by the Executive in the performance of his duties and responsibilities hereunder, subject to reasonable substantiation and documentation as may be specified by the Company from time to time.

8. TERMINATION OF EMPLOYMENT : The Employment Period (and thereby the Executive’s employment hereunder) may be terminated as set forth below.

(a) Death . In the event of the Executive’s death during the term hereof, the Employment Period shall immediately and automatically terminate. In that event, the Company shall pay to the Executive’s designated beneficiary or, if no beneficiary has been designated by the Executive, to his estate, any earned and unpaid Base Salary, prorated through the date of his death. The Company shall have no further obligation or liability to the Executive or his estate.

(b) Disability .

(i) The Company may terminate the Employment Period, upon notice to the Executive, in the event that the Executive becomes disabled during his employment hereunder through any illness, injury, accident or condition of either a physical or psychological nature and, as a result, is unable to perform the essential functions of his position hereunder, with or without reasonable accommodation, for ninety (90) days during any period of three hundred sixty-five (365) consecutive calendar days.

(ii) The Board may designate another employee to act in the Executive’s place during any period in which the Executive is unable to perform the essential functions of his position as a result of any illness, injury, accident or condition of either a physical or psychological nature. Notwithstanding any such designation, the Executive shall continue to receive the Base Salary in accordance with Section 3 and his other benefits pursuant to Section 6, to the extent permitted by the then-current terms of the applicable benefit plans, until the Executive becomes eligible for disability income benefits under any disability income plan provided by the Company or until the termination of his employment, whichever shall first occur.

(iii) If any question shall arise as to whether during any period the Executive is disabled through any illness, injury, accident or condition of either a physical or psychological nature so as to be unable to perform the essential functions of his position hereunder, the Executive may, and at the request of the Company shall, submit to a medical examination by a physician designated by agreement between the Company and the Executive or his duly appointed guardian, if any, to determine whether the Executive is so disabled, and such determination shall for the purposes of this Agreement be conclusive of the issue. If such question shall arise and the Executive shall fail to submit to such medical examination, the Company’s determination of the issue shall be binding on the Executive.

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(c) By the Company for Cause . The Company may terminate the Employment Period hereunder for Cause (as defined below) at any time upon notice to the Executive setting forth in reasonable detail the nature of such Cause. The following, as determined by the Board in its reasonable and good faith judgment, shall constitute Cause for termination: (i) conviction or plea of nolo contendere in a court of law of (x) any felony or (y) any misdemeanor involving dishonesty, breach of trust, misappropriation or illegal narcotics, (ii) commission of any act involving theft, embezzlement, fraud, dishonesty or moral turpitude or that otherwise impairs the reputation, goodwill or business of the Company, (iii) material breach of any of the material provisions of this Agreement or of any other material agreement between the Executive and the Company or any of its Affiliates, (iv) demonstration of gross negligence, willful misconduct or dereliction of duty in the execution of his duties under this Agreement or breach of his duty of loyalty to the Company or any of its Affiliates that is materially injurious to the Company, or (v) repeated and consistent failure to be present at work or to perform his duties at a level consistent with his position with the Company. Upon the giving of notice of termination of the Executive’s employment hereunder for Cause, the Company shall not have any further obligation or liability to the Executive, other than for Base Salary earned and unpaid through the date of termination. Notwithstanding the foregoing, following written notice from the Board of Directors of any of the events described in (iii) or (v) above (such notice to set forth in reasonable detail the nature of the alleged breach or conduct): (x) the Executive shall have thirty (30) calendar days in which to cure the alleged breach or conduct, except where such breach or conduct by its nature may not be cured, and (y) if the Executive fails to cure, the Executive’s termination shall become effective on the 31st calendar day following such written notice.

(d) By the Company without Cause . The Company may terminate the Employment Period hereunder without Cause at any time upon notice.

(e) By the Executive . The Executive may terminate the Employment Period hereunder, with or without cause, at any time upon at least thirty (30) days’ advance written notice to the Company.

9. SEVERANCE BENEFITS : In the event that the Executive’s employment terminates without Cause pursuant to Section 8(d), the Executive shall be entitled, subject to the requirements of Section 9(c), to receive the following severance benefits (the “Severance Benefits”):

(a) Salary and Health Care Benefit Continuation :

(i) The Company will pay the Executive installments of his Base Salary in effect as of the last day of the Employment Period for a period of three (3) months from and after the date of such termination (the “Severance Period”); and

(ii) The Company will either (A) continue the Executive’s group health plan benefits to the extent authorized by and consistent with 29 U.S.C. § 1161 et seq. (commonly known as “COBRA”), with the cost of the regular employer portion of the

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premium for such benefits paid by the Company during the Severance Period, or (B) in the event that as of the date of termination of the Executive’s employment the Company was reimbursing the Executive for the cost of maintaining his current family medical insurance coverage pursuant to Section 6, continue such reimbursement during the Severance Period.

In the event that a Change in Control (as defined below) occurs and the Executive’s employment with the Company or the successor/acquiror of the Company