Exhibit 4.4
                               PURCHASE AGREEMENT


          THIS PURCHASE AGREEMENT ("Agreement") is made as of the 15th day of
September, 2004 by and among World Heart Corporation, a corporation incorporated
under the laws of the Province of Ontario, Canada (the "Company"), and the
Investors set forth on the signature pages affixed hereto (each an "Investor"
and collectively the "Investors").

                                    Recitals

          A.  The Company and the Investors are executing and delivering this
Agreement in reliance upon the exemption from securities registration afforded
by the provisions of Regulation D ("Regulation D"), as promulgated by the U.S.
Securities and Exchange Commission (the "SEC") under the Securities Act of 1933,
as amended; and

          B.  The Investors wish to purchase from the Company, and the Company
wishes to sell and issue to the Investors, upon the terms and conditions stated
in this Agreement, up to a minimum of US$12,000,000 and a maximum of
US$20,000,000 (the "Offering") unsecured convertible debentures ("Debentures")
and common share purchase warrants of the Company at a rate of one warrant for
each US$1.25 principal amount of Debentures (a "Warrant" or collectively, the
"Warrants"). The Debentures will be convertible, at the option of the holder,
into common shares at a rate, subject to adjustment, of US$1.25 principal amount
of Debentures per Common Share for a period of 60 months from the Closing Date.

          C.  The form of Debenture is attached to the Agreement as Exhibit A
and the form of the Warrant is attached to the Agreement as Exhibit B.

          D.  Contemporaneous with the sale of the Debentures and the Warrants,
the parties hereto will execute and deliver a Registration Rights Agreement, in
the form attached hereto as Exhibit C (the "Registration Rights Agreement"),
pursuant to which the Company will agree to provide certain registration rights
under the Securities Act of 1933, as amended, and the rules and regulations
promulgated thereunder, and applicable state securities laws.

          In consideration of the mutual promises made herein and for other good
and valuable consideration, the receipt and sufficiency of which is hereby
acknowledged, the parties hereto agree as follows:

     1.   Definitions. In addition to those terms defined above and elsewhere in
this Agreement, for the purposes of this Agreement, the following terms shall
have the meanings here set forth:

          "Affiliate" means, with respect to any Person, any other Person which
directly or indirectly Controls, is controlled by, or is under common control
with, such Person.

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          "Business Day" means a day, other than a Saturday or Sunday, on which
banks in New York City and Ottawa, Ontario are open for the general transaction
of business.

          "Common Stock" means the common shares of the Company, and any
securities into which the Common Stock may be reclassified.

          "Company's Knowledge" means the actual knowledge of the officers of
the Company, after due inquiry.

          "Confidential Information" means trade secrets, confidential
information and know-how (including but not limited to ideas, formulae,
compositions, processes, procedures and techniques, research and development
information, computer program code, performance specifications, support
documentation, drawings, specifications, designs, business and marketing plans,
and customer and supplier lists and related information).

          "Control" means the possession, direct or indirect, of the power to
direct or cause the direction of the management and policies of a Person,
whether through the ownership of voting securities, by contract or otherwise.

          "Debentures" has the meaning ascribed thereto in the recitals of this
Agreement.

          "Debenture Shares" means the Common Stock issuable upon the conversion
of the Debentures.

          "Dollars" or "$" means United States dollars.

          "Effective Date" means the date on which the initial Registration
Statement (as defined in the Registration Rights Agreement) is declared
effective by the SEC.

          "Effectiveness Deadline" means the date on which the initial
Registration Statement (as defined in the Registration Rights Agreement) is
required to be declared effective by the SEC under the terms of the Registration
Rights Agreement.

          "Intellectual Property" means all of the following: (i) patents,
patent applications, patent disclosures and inventions (whether or not
patentable and whether or not reduced to practice); (ii) trademarks, service
marks, trade dress, trade names, corporate names, logos, slogans and Internet
domain names, together with all goodwill associated with each of the foregoing;
(iii) copyrights and copyrightable works; (iv) registrations, applications and
renewals for any of the foregoing; and (v) proprietary computer software
(including but not limited to data, data bases and documentation).

          "Interest" means the interest at the rate of 3% per annum (accrued but
not compounded) calculated on the outstanding principal amount of the
Debentures.

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          "Interest Shares" means the shares of Common Stock issuable upon the
conversion of the Interest under the terms and conditions set forth in the
Debentures.

          "Material Adverse Effect" means a material adverse effect on (i) the
assets, liabilities, results of operations, condition (financial or otherwise),
business, or prospects of the Company and its Subsidiaries taken as a whole, or
(ii) the ability of the Company to perform its obligations under the Transaction
Documents.

          "NASDAQ" means the NASDAQ National Market, its successors and assigns.

          "Person" means an individual, corporation, partnership, limited
liability company, trust, business trust, association, joint stock company,
joint venture, sole proprietorship, unincorporated organization, governmental
authority or any other form of entity not specifically listed herein.

          "Purchase Price" means 100% of the principal amount of the Debentures.

          "Registration Rights Agreement" has the meaning set forth in the
recitals to this Agreement.

          "SEC" means the United States Securities and Exchange Commission.

          "SEC Filings" has the meaning set forth in Section 4.6.

          "Securities" means the Debentures, the Debenture Shares, the Interest
Shares, Warrants and the Warrant Shares.

          "Subsidiary" has the meaning set forth in Section 4.1.

          "Transaction Documents" means this Agreement, the Registration Rights
Agreement, the Warrant Indenture, the Debentures and the Warrants.

          "TSX" means the Toronto Stock Exchange Inc., its successors and
assigns.

          "Warrant" has the meaning ascribed thereto in the recitals to this
Agreement.

          "Warrant Indenture" means the Warrant Indenture to be entered into by
the Company and CIBC Mellon Trust Company, as warrant agent, in substantially
the form of Exhibit D attached hereto.

          "Warrant Shares" means the shares of Common Stock issuable upon
exercise of the Warrants.

          "1933 Act" means the Securities Act of 1933, as amended, and the rules
and regulations promulgated thereunder.

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          "1934 Act" means the Securities Exchange Act of 1934, as amended, and
the rules and regulations promulgated thereunder.

     2.   Purchase and Sale of the Debentures and Warrants. Subject to the terms
and conditions of this Agreement, on the Closing Date, each of the Investors
shall severally, and not jointly, purchase, and the Company shall sell and issue
to the Investors, the Debentures and Warrants in the respective principal
amounts and numbers set forth opposite the Investors' names on the signature
pages attached hereto in exchange for the Purchase Price as specified in Section
3 below.

     3.   Closing. Upon confirmation that the other conditions to closing
specified herein have been satisfied, the Company shall deliver to Lowenstein
Sandler PC, in trust, the Debentures and certificates representing the Warrants,
registered in such name or names as the Investors may designate, with
instructions that such Debentures and certificates are to be held for release to
the Investors only upon payment of the Purchase Price to the Company. Upon
receipt by Lowenstein Sandler PC of the Debentures and such certificates, each
Investor shall promptly cause a wire transfer in same day funds to be sent to
the account of the Company as instructed in writing by the Company, in an amount
representing such Investor's pro rata portion of the Purchase Price as set forth
on the signature pages to this Agreement. On the date (the "Closing Date") the
Company receives such funds and the Debentures and the certificates evidencing
the Warrants shall be released to the Investors (the "Closing"). The purchase
and sale of the Debentures and the Warrants shall take place at the offices of
Lowenstein Sandler PC, 1330 Avenue of the Americas, 21st Floor, New York, New
York, or at such other location and on such other date as the Company and the
Investors shall mutually agree.

     4.   Representations and Warranties of the Company. The Company hereby
represents and warrants to the Investors that, except as set forth in the
schedules delivered herewith (collectively, the "Disclosure Schedules"):

          4.1 Organization, Good Standing and Qualification. Each of the
Company and its Subsidiaries is a corporation duly organized, validly existing
and in good standing under the laws of the jurisdiction of its incorporation and
has all requisite corporate power and authority to carry on its business as now
conducted and to own its properties. Each of the Company and its Subsidiaries is
duly qualified to do business as a foreign corporation and is in good standing
in each jurisdiction in which the conduct of its business or its ownership or
leasing of property makes such qualification or leasing necessary unless the
failure to so qualify has not and could not reasonably be expected to have a
Material Adverse Effect. The Company's subsidiaries are reflected on Schedule
4.1 hereto (the "Subsidiaries").

          4.2 Authorization. The Company has full power and authority and has
taken all requisite action on the part of the Company, its officers, directors
and shareholders necessary for (i) the authorization, execution and delivery of
the Transaction Documents, (ii) authorization of the performance of all
obligations of the Company hereunder or thereunder, and (iii) the authorization,
issuance (or reservation for issuance) and delivery of the Securities. The
Transaction Documents constitute the legal, valid and binding obligations of the
Company, enforceable against the Company in accordance with their terms, subject
to bankruptcy,

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insolvency, fraudulent transfer, reorganization, moratorium and similar laws of
general applicability, relating to or affecting creditors' rights generally.

          4.3 Capitalization. Schedule 4.3 sets forth (a) the authorized capital
stock of the Company on the date hereof; (b) the number of shares of capital
stock issued and outstanding; (c) the number of shares of capital stock issuable
pursuant to the Company's stock plans; and (d) the number of shares of capital
stock issuable and reserved for issuance pursuant to securities (other than the
Securities) exercisable for, or convertible into or exchangeable for any shares
of capital stock of the Company. All of the issued and outstanding shares of the
Company's capital stock have been duly authorized and validly issued and are
fully paid, non-assessable and free of pre-emptive rights and were issued in
full compliance with applicable law and any rights of third parties. All of the
issued and outstanding shares of capital stock of each Subsidiary have been duly
authorized and validly issued and are fully paid, non-assessable and free of
pre-emptive rights, were issued in full compliance with applicable law and any
rights of third parties and are owned by the Company, beneficially and of
record, subject to no lien, encumbrance or other adverse claim. No Person is
entitled to pre-emptive or similar statutory or contractual rights with respect
to any securities of the Company. Except as described on Schedule 4.3, there are
no outstanding warrants, options, convertible securities or other rights,
agreements or arrangements of any character under which the Company or any of
its Subsidiaries is or may be obligated to issue any equity securities of any
kind and except as contemplated by this Agreement, neither the Company nor any
of its Subsidiaries is currently in negotiations for the issuance of any equity
securities of any kind. Except as described on Schedule 4.3 and except for the
Registration Rights Agreement, there are no voting agreements, buy-sell
agreements, option or right of first purchase agreements or other agreements of
any kind among the Company and any of the securityholders of the Company
relating to the securities of the Company held by them. The Company has not
granted any Person the right to require the Company to register any securities
of the Company under the 1933 Act, whether on a demand basis or in connection
with the registration of securities of the Company for its own account or for
the account of any other Person.

          Schedule 4.3 sets forth a true and complete table setting forth the
pro forma capitalization of the Company on a fully diluted basis giving effect
to (i) the issuance of the Debentures and the Warrants, (ii) any adjustments in
other securities resulting from the issuance of the Debentures or the Warrants,
and (iii) the exercise or conversion of all outstanding securities. Except as
described on Schedule 4.3, the issuance and sale of the Debentures and the
Warrants hereunder will not obligate the Company to issue shares of Common Stock
or other securities to any other Person (other than the Investors) and will not
result in the adjustment of the exercise, conversion, exchange or reset price of
any outstanding security.

          The Company does not have outstanding shareholder purchase rights or
any similar arrangement in effect giving any Person the right to purchase any
equity interest in the Company upon the occurrence of certain events.

          4.4 Valid Issuance. The Debentures have been duly and validly
authorized. Upon the due conversion of the Debentures and Interest, the
Debenture Shares and the Interest Shares will be validly issued, fully paid and
non-assessable and shall be free and clear of all

<PAGE>

encumbrances and restrictions, except for restrictions on transfer set forth in
the Transaction Documents or imposed by applicable securities laws. The
Warrants have been duly and validly authorized. Upon the due exercise of the
Warrants, the Warrant Shares will be validly issued, fully paid and
non-assessable free and clear of all encumbrances and restrictions, except for
restrictions on transfer set forth in the Transaction Documents or imposed by
applicable securities laws. The Company has reserved a sufficient number of
shares of Common Stock for issuance upon the conversion of the Debentures, the
Interest and upon the exercise of the Warrants, free and clear of all
encumbrances and restrictions, except for restrictions on transfer set forth in
the Transaction Documents or imposed by applicable securities laws.

          4.5 Consents. The execution, delivery and performance by the Company
of the Transaction Documents and the offer, issuance and sale of the Securities
require no consent of, action by or in respect of, or filing with, any Person,
governmental body, agency, or official other than (i) approvals required to be
obtained by the TSX and NASDAQ, all of which shall be obtained and shall be in
full force and effect prior to the Closing, and (ii) filings that have been made
pursuant to applicable securities laws and post-sale filings pursuant to
applicable state, federal and provincial securities laws which the Company
undertakes to file within the applicable time periods. The Company has taken all
action necessary to exempt (i) the issuance and sale of the Debentures and
Warrants, (ii) the issuance of the Debenture Shares and the Interest Shares upon
the due conversion of the Debentures and the Interest, (iii) the issuance of the
Warrant Shares upon due exercise of the Warrants, and (iv) the other
transactions contemplated by the Transaction Documents from the provisions of
any anti-takeover, business combination or control share law or statute binding
on the Company or to which the Company or any of its assets and properties may
be subject or any provision of the Company's articles of incorporation, by-laws
or any shareholder rights agreement that is or could become applicable to the
Investors as a result of the transactions contemplated hereby, including without
limitation, the issuance of the Securities and the ownership, disposition or
voting of the Securities by the Investors or the exercise of any right granted
to the Investors pursuant to this Agreement or the other Transaction Documents.

          4.6 Delivery of SEC Filings; Business. The Company has provided the
Investors with copies of the Company's most recent Annual Report on Form 40-F
for the fiscal year ended December 31, 2003 (the "40-F"), and all other reports
filed by the Company pursuant to the 1934 Act since the filing of the 40-F and
prior to the date hereof (collectively, the "SEC Filings"). The SEC Filings are
the only filings required of the Company pursuant to the 1934 Act for such
period. The Company and its Subsidiaries are engaged only in the business
described in the SEC Filings and the SEC Filings contain a complete and accurate
description in all material respects of the business of the Company and its
Subsidiaries, taken as a whole.

          4.7 Use of Proceeds. The proceeds of the sale of the Debentures and
the Warrants hereunder shall be used by the Company for funding ongoing
operations including the RELIANT Trial, manufacturing of the Novacor LVAS
products, sales and marketing efforts, research and development, restructuring
costs and general corporate purposes.

          4.8  No Material Adverse Change. Since December 31, 2003, except as
identified and described in the SEC Filings or as described on Schedule 4.8,
there has not been:
<PAGE>

               (i) any change in the consolidated assets, liabilities, financial
condition or operating results of the Company from that reflected in the
financial statements included in the 40-F, except for changes in the ordinary
course of business which have not and could not reasonably be expected to have a
Material Adverse Effect, individually or in the aggregate;

              (ii) any declaration or payment of any dividend, or any
authorization or payment of any distribution, on any of the capital stock of the
Company, or any redemption or repurchase of any securities of the Company;

             (iii) any material damage, destruction or loss, whether or not
covered by insurance to any assets or properties of the Company or its
Subsidiaries;

              (iv) any waiver, not in the ordinary course of business, by the
Company or any Subsidiary of a material right or of a material debt owed to it;

               (v) any satisfaction or discharge of any lien, claim or
encumbrance or payment of any obligation by the Company or a Subsidiary, except
in the ordinary course of business and which is not material to the assets,
properties, financial condition, operating results or business of the Company
and its Subsidiaries taken as a whole (as such business is presently conducted
and as it is proposed to be conducted);

              (vi) any change or amendment to the Company's articles of
incorporation or by-laws, or material change to any material contract or
arrangement by which the Company or any Subsidiary is bound or to which any of
their respective assets or properties is subject;

             (vii) any material labor difficulties or labor union organizing
activities with respect to employees of the Company or any Subsidiary;

            (viii) any transaction entered into by the Company or a
Subsidiary other than in the ordinary course of business;
<PAGE>

              (ix) the loss of the services of any key employee, or material
change in the composition or duties of the senior management of the Company or
any Subsidiary;

               (x) the loss or threatened loss of any customer which has had or
could reasonably be expected to have a Material Adverse Effect; or

              (xi) any other event or condition of any character that has had
or could reasonably be expected to have a Material Adverse Effect.

          4.9 SEC Filings; 1933 Act Registration Form
              ---------------------------------------
<PAGE>

              (a) At the time of filing thereof, the SEC Filings complied as to
form in all material respects with the requirements of the 1934 Act and did not
contain any untrue statement of a material fact or omit to state any material
fact necessary in order to make the statements made therein, in the light of the
circumstances under which they were made, not misleading.

              (b) Each registration statement and any amendment thereto filed
by the Company since January 1, 2002 pursuant to the 1933 Act and the rules and
regulations thereunder, as of the date such statement or amendment became
effective, complied as to form in all material respects with the 1933 Act and
did not contain any untrue statement of a material fact or omit to state any
material fact required to be stated therein or necessary in order to make the
statements made therein, in light of the circumstances under which they were
made, not misleading; and each prospectus filed pursuant to Rule 424(b) under
the 1933 Act, as of its issue date and as of the closing of any sale of
securities pursuant thereto did not contain any untrue statement of a material
fact or omit to state any material fact required to be stated therein or
necessary in order to make the statements made therein, in the light of the
circumstances under which they were made, not misleading.

              (c) The Company is eligible to use Form F-3 or an appropriate
form under the 1933 Act to register the Registrable Securities (as such term is
defined in the Registration Rights Agreement) for sale by the Investors as
contemplated by the Registration Rights Agreement. The Company will provide
written notice to the Investors at least 15 days prior to the Company ceasing to
be eligible to use Form F-3.

          4.10 No Conflict, Breach, Violation or Default. The execution,
delivery and performance of the Transaction Documents by the Company and the
issuance and sale of the Securities will not conflict with or result in a breach
or violation of any of the terms and provisions of, or constitute a default
under (i) the Company's Articles of Incorporation or the Company's Bylaws, both
as in effect on the date hereof (copies of which have been provided to the
Investors before the date hereof), or (ii)(a) any statute, rule, regulation or
order of any governmental agency or body or any court, domestic or foreign,
having jurisdiction over the Company, any Subsidiary or any of their respective
assets or properties, or (b) any agreement or instrument to which the Company or
any Subsidiary is a party or by which the Company or a Subsidiary is bound or to
which any of their respective assets or properties is subject.

          4.11 Tax Matters. The Company and each Subsidiary has timely prepared
and filed all material tax returns required to have been filed by the Company or
such Subsidiary with all appropriate governmental agencies and timely paid all
taxes shown thereon or otherwise owed by it. The charges, accruals and reserves
on the books of the Company in respect of taxes for all fiscal periods are
adequate in all material respects, and there are no material unpaid assessments
against the Company or any Subsidiary nor, to the Company's Knowledge, any basis
for the assessment of any additional taxes, penalties or interest for any fiscal
period or audits by any federal, state, local or provincial taxing authority
except for any assessment which is not material to the Company and its
Subsidiaries, taken as a whole. All material taxes and other assessments and
levies that the Company or any Subsidiary is required to withhold or to collect
for payment have been duly withheld and collected and paid to the proper
governmental

<PAGE>

entity or third party when due. There are no tax liens or claims pending or, to
the Company's Knowledge, threatened against the Company or any Subsidiary or
any of their respective assets or property. Except as described on Schedule
4.11, there are no outstanding tax sharing agreements or other such arrangements
between the Company and any Subsidiary or other corporation or entity.

          4.12 Title to Properties. Except as disclosed in the SEC Filings or as
described on Schedule 4.12, the Company and each Subsidiary has good and
marketable title to all real properties and all other properties and assets
owned by it, in each case free from liens, encumbrances and defects that would
materially affect the value thereof or materially interfere with the use made or
currently planned to be made thereof by them; and except as disclosed in the SEC
Filings, the Company and each Subsidiary holds any leased real or personal
property under valid and enforceable leases with no exceptions that would
materially interfere with the use made or currently planned to be made thereof
by them.

          4.13 Certificates, Authorities and Permits. The Company and each
Subsidiary possess adequate certificates, authorities or permits issued by
appropriate governmental agencies or bodies necessary to conduct the business
now operated by it, and neither the Company nor any Subsidiary has received any
notice of proceedings relating to the revocation or modification of any such
certificate, authority or permit that, if determined adversely to the Company or
such Subsidiary, could reasonably be expected to have a Material Adverse Effect,
individually or in the aggregate.

          4.14 No Labor Disputes. No material labor dispute with the employees
of the Company or any Subsidiary exists or, to the Company's
Knowledge, is imminent.

          4.15 Intellectual Property.
               ---------------------

              (a) All Intellectual Property of the Company and its Subsidiaries
is currently in compliance with all legal requirements (including timely
filings, proofs and payments of fees) and is valid and enforceable. To the
Company's Knowledge, no Intellectual Property of the Company or its Subsidiaries
which is material to the conduct of Company's and each of its Subsidiaries'
respective businesses as currently conducted or as currently proposed to be
conducted has been or is now involved in any cancellation, dispute or
litigation, and, to the Company's Knowledge, no such action is threatened. To
the Company's Knowledge, no material patent of the Company or its Subsidiaries
has been or is now involved in any interference, reissue, re-examination or
opposition proceeding.

              (b) All of the licenses and sublicenses and consent, royalty or
other agreements concerning Intellectual Property which are material to the
conduct of the Company's and each of its Subsidiaries' respective businesses as
currently conducted or as currently proposed to be conducted to which the
Company or any Subsidiary is a party or by which any of their assets are bound
(other than generally commercially available, non-custom, off-the-shelf software
application programs having a retail acquisition price of less than $10,000 per
license) (collectively, "License Agreements") are valid and binding obligations
of the Company or its Subsidiaries that are parties thereto and, to the
Company's Knowledge, the other parties thereto,

<PAGE>

enforceable in accordance with their terms, except to the extent that
enforcement thereof may be limited by bankruptcy, insolvency, reorganization,
moratorium, fraudulent conveyance or other similar laws affecting the
enforcement of creditors' rights generally, and there exists no event or
condition which will result in a material violation or breach of or constitute
(with or without due notice or lapse of time or both) a default by the Company
or any of its Subsidiaries under any such License Agreement.

              (c) The Company and its Subsidiaries own or have the valid right
to use all of the Intellectual Property that is material to the conduct of the
Company's and each of its Subsidiaries' respective businesses as currently
conducted or as currently proposed to be conducted and for the ownership,
maintenance and operation of the Company's and its Subsidiaries' properties and
assets, free and clear of all liens, encumbrances, adverse claims or obligations
to license all such owned Intellectual Property and Confidential Information,
other than licenses entered into in the ordinary course of the Company's and its
Subsidiaries' businesses. The Company and its Subsidiaries have a valid and
enforceable right to use all third party Intellectual Property and Confidential
Information used or held for use in the respective businesses of the Company and
its Subsidiaries.

              (d) To the Company's Knowledge, the conduct of the Company's and
its Subsidiaries' businesses as currently conducted does not infringe or
otherwise impair or conflict with (collectively, "Infringe") any Intellectual
Property rights of any third party or any confidentiality obligation owed to a
third party, and the Intellectual Property and Confidential Information of the
Company and its Subsidiaries which are material to the conduct of Company's and
each of its Subsidiaries' respective businesses as currently conducted or as
currently proposed to be conducted are not being Infringed by any third party.
There is no litigation or order pending or outstanding or, to the Company's
Knowledge, threatened or imminent, that seeks to limit or challenge or that
concerns the ownership, use, validity or enforceability of any Intellectual
Property or Confidential Information of the Company and its Subsidiaries and the
Company's and its Subsidiaries' use of any Intellectual Property or Confidential
Information owned by a third party, and, to the Company's Knowledge, there is no
valid basis for the same.

              (e) The consummation of the transactions contemplated hereby will
not result in the alteration, loss, impairment of or restriction on the
Company's or any of its Subsidiaries' ownership or right to use any of the
Intellectual Property or Confidential Information which is material to the
conduct of the Company's and each of its Subsidiaries' respective businesses as
currently conducted or as currently proposed to be conducted.

              (f) To the Company's Knowledge, as currently used all software
owned by the Company or any of its Subsidiaries and all software licensed from
third parties by the Company or any of its Subsidiaries, (i) is free from any
material defect, bug, virus, or programming, design or documentation error; (ii)
operates and runs in a reasonable and efficient business manner; and (iii)
conforms in all material respects to the specifications and purposes thereof.

<PAGE>

              (g) The Company and its Subsidiaries have taken reasonable steps
to protect the Company's and its Subsidiaries' rights in their Intellectual
Property and Confidential Information. Each employee, consultant and contractor
who has had access to Confidential Information which is material to the conduct
of the Company's and each of its Subsidiaries' respective businesses as
currently conducted or as currently proposed to be conducted has either (i)
executed an agreement to maintain the confidentiality of such Confidential
Information; (ii) executed appropriate agreements that are substantially
consistent with the Company's standard forms thereof or (iii) undertaken similar
safeguards to protect and preserve the confidentiality of all Confidential
Information. Except under confidentiality obligations, to the Company's
Knowledge there has been no material disclosure of any of the Company's or its
Subsidiaries' Confidential Information to any third party.

          4.16 Environmental Matters. Neither the Company nor any Subsidiary is
in violation of any statute, rule, regulation, decision or order of any
governmental agency or body or any court, domestic or foreign, relating to the
use, disposal or release of hazardous or toxic substances or relating to the
protection or restoration of the environment or human exposure to hazardous or
toxic substances (collectively, "Environmental Laws"), owns or operates any real
property contaminated with any substance that is subject to any Environmental
Laws, is liable for any off-site disposal or contamination pursuant to any
Environmental Laws, and is subject to any claim relating to any Environmental
Laws, which violation, contamination, liability or claim has had or could
reasonably be expected to have a Material Adverse Effect, individually or in the
aggregate; and to the Company's Knowledge there is no pending or threatened
investigation that might lead to such a claim.

          4.17 Litigation. Except as described on Schedule 4.17, there are no
pending actions, suits or proceedings against or affecting the Company, its
Subsidiaries or any of its or their properties; and to the Company's Knowledge,
no such actions, suits or proceedings are threatened or contemplated.

          4.18 Financial Statements. The financial statements included in each
SEC Filing present fairly, in all material respects, the consolidated financial
position of the Company as of the dates shown and its consolidated results of
operations and cash flows for the periods shown, and such financial statements
have been prepared in conformity with Canadian generally accepted accounting
principles applied on a consistent basis (except as may be disclosed therein or
in the notes thereto). Except as set forth in the financial statements of the
Company included in the SEC Filings filed prior to the date hereof or as
described on Schedule 4.18, neither the Company nor any of its Subsidiaries has
incurred any liabilities, contingent or otherwise, except those incurred in the
ordinary course of business, consistent (as to amount and nature) with past
practices since the date of such financial statements, none of which,
individually or in the aggregate, have had or could reasonably be expected to
have a Material Adverse Effect.

          4.19 Insurance Coverage. The Company and each Subsidiary maintains in
full force and effect insurance coverage that is customary for comparably
situated companies for the business being conducted and properties owned or
leased by the Company and each Subsidiary, and the Company reasonably believes
such insurance coverage to be adequate against all


<PAGE>

liabilities, claims and risks against which it is customary for comparably
situated companies to insure.

          4.20 Compliance with TSX and NASDAQ Continued Listing Requirements.
The Company is in compliance with applicable TSX and NASDAQ continued listing
requirements. There are no proceedings pending or, to the Company's Knowledge,
threatened against the Company relating to the continued listing of the
Company's Common Stock on the TSX or on NASDAQ and the Company has not received
any notice of, nor to the Company's Knowledge is there any basis for, the
delisting of the Common Stock from the TSX or NASDAQ.

          4.21 Brokers and Finders. No Person will have, as a result of the
transactions contemplated by this Agreement, any valid right, interest or claim
against or upon the Company, any Subsidiary or an Investor for any commission,
fee or other compensation pursuant to any agreement, arrangement or
understanding entered into by or on behalf of the Company, other than as
described in Schedule 4.21.

          4.22 No Directed Selling Efforts or General Solicitation. Neither the
Company nor any Person acting on its behalf has conducted any general
solicitation or general advertising (as those terms are used in Regulation D) in
connection with the offer or sale of any of the Securities.

          4.23 No Integrated Offering. Neither the Company nor any of its
Affiliates, nor any Person acting on its or their behalf has, directly or
indirectly, made any offers or sales of any Company security or solicited any
offers to buy any security, under circumstances that would adversely affect
reliance by the Company on Section 4(2) for the exemption from registration for
the transactions contemplated hereby or would require registration of the
Securities under the 1933 Act.

          4.24 Private Placement. The offer and sale of the Securities to the
Investors as contemplated hereby is exempt from the registration requirements of
the 1933 Act. The offer and sale of the Debentures as contemplated hereby is
exempt from the requirements of the Trust Indenture Act of 1939, as amended.

          4.25 Questionable Payments. Neither the Company nor any of its
Subsidiaries nor, to the Company's Knowledge, any of their respective current or
former shareholders, directors, officers, employees, agents or other Persons
acting on behalf of the Company or any Subsidiary, has on behalf of the Company
or any Subsidiary or in connection with their respective businesses: (a) used
any corporate funds for unlawful contributions, gifts, entertainment or other
unlawful expenses relating to political activity; (b) made any direct or
indirect unlawful payments to any governmental officials or employees from
corporate funds; (c) established or maintained any unlawful or unrecorded fund
of corporate monies or other assets; (d) made any false or fictitious entries on
the books and records of the Company or any Subsidiary; or (e) made any unlawful
bribe, rebate, payoff, influence payment, kickback or other unlawful payment of
any nature.
<PAGE>

          4.26 Transactions with Affiliates. Except as disclosed in SEC Filings
made on or prior to the date hereof or as disclosed on Schedule 4.26, none of
the officers or directors of the Company and, to the knowledge of the Company,
none of the employees of the Company is presently a party to any transaction
with the Company or any Subsidiary (other than as holders of stock options
and/or warrants, and for services as employees, officers and directors),
including any contract, agreement or other arrangement providing for the
furnishing of services to or by, providing for rental of real or personal
property to or from, or otherwise requiring payments to or from any officer,
director or such employee or, to the knowledge of the Company, any entity in
which any officer, director, or any such employee has a substantial interest or
is an officer, director, trustee or partner.

          4.27 Internal Controls. The Company and the Subsidiaries maintain a
system of internal accounting controls sufficient to provide reasonable
assurance that (i) transactions are executed in accordance with management's
general or specific authorizations, (ii) transactions are recorded as necessary
to permit preparation of financial statements in conformity with generally
accepted accounting principles and to maintain asset accountability, (iii)
access to assets is permitted only in accordance with management's general or
specific authorization, and (iv) the recorded accountability for assets is
compared with the existing assets at reasonable intervals and appropriate action
is taken with respect to any differences.

          4.28 Disclosures. Neither the Company nor any Person acting on its
behalf has provided the Investors or their agents or counsel with any
information that constitutes or might constitute material, non-public
information. The written materials delivered to the Investors in connection with
the transactions contemplated by the Transaction Documents do not contain any
untrue statement of a material fact or omit to state a material fact necessary
in order to make the statements contained therein, in light of the circumstances
under which they were made, not misleading.

     5.   Representations, Warranties and Covenants of the Investors. Each of
the Investors hereby severally, and not jointly, represents and warrants to, and
covenants with, the Company that:

          5.1 Organization and Existence. The Investor is a validly existing
corporation, limited partnership or limited liability company and has all
requisite corporate, partnership or limited liability company power and
authority to invest in the Securities pursuant to this Agreement.

          5.2 Authorization. The execution, delivery and performance by the
Investor of the Transaction Documents to which such Investor is a party have
been duly authorized and will each constitute the valid and legally binding
obligation of the Investor, enforceable against the Investor in accordance with
their respective terms, subject to bankruptcy, insolvency, fraudulent transfer,
reorganization, moratorium and similar laws of general applicability, relating
to or affecting creditors' rights generally.

          5.3 Purchase Entirely for Own Account. The Securities to be received
by the Investor hereunder will be acquired for the Investor's own account, not
as nominee or agent, and
<PAGE>

not with a view to the resale or distribution of any part thereof in violation
of the 1933 Act, and the Investor has no present intention of selling, granting
any participation in, or otherwise distributing the same in violation of the
1933 Act. The Investor is not a registered broker dealer or an entity engaged in
the business of being a broker dealer.

          5.4 Investment Experience. The Investor acknowledges that it can bear
the economic risk and complete loss of its investment in the Securities and has
such knowledge and experience in financial or business matters that it is
capable of evaluating the merits and risks of the investment contemplated
hereby.

          5.5 Disclosure of Information. The Investor has had an opportunity to
receive all additional information related to the Company requested by it and to
ask questions of and receive answers from the Company regarding the Company, its
business and the terms and conditions of the offering of the Securities. The
Investor acknowledges receipt of copies of the SEC Filings. Neither such
inquiries nor any other due diligence investigation conducted by the Investor
shall modify, amend or affect the Investor's right to rely on the Company's
representations and warranties contained in this Agreement.

          5.6 Restricted Securities. The Investor understands that the
Securities are characterized as "restricted securities" under the U.S. federal
securities laws inasmuch as they are being acquired from the Company in a
transaction not involving a public offering and that under such laws and
applicable regulations such securities may be resold without registration under
the 1933 Act only in certain limited circumstances. The Investor also
understands that the Debentures and the Warrants have not been and will not be
registered under the 1933 Act or any applicable state securities laws and that
the offer and sale of the Debentures and the Warrants to it is being made in
reliance on an exemption from registration contained in the 1933 Act and
applicable state securities laws based upon the representations of the Investor
contained herein.

          The Investor, by purchasing the Securities, agrees for the benefit of
the Company that if it decides to offer, sell, pledge or otherwise transfer any
of the Securities, such Securities may be offered, sold, pledged or otherwise
transferred only (a) to the Company, (b) outside the United States in accordance
with Rule 903 or Rule 904 of Regulation S under the 1933 Act, if applicable (c)
inside the United States (1) pursuant to the exemption from the registration
requirements under the 1933 Act provided by rule 144 thereunder, if available,
and in accordance with applicable state securities law or (2) in a transaction
that does not otherwise require registration under the 1933 Act or any
applicable state securities law, provided the holder has furnished to the
Company an opinion of counsel of recognized standing to that effect in form and
substance reasonably satisfactory to the Company or (3) pursuant to a
registration statement pursuant to the 1933 Act.

          5.7 Legends. It is understood that, except as provided below,
certificates evidencing such Securities may bear the following or any similar
legend:

               (a) THE SECURITIES REPRESENTED HEREBY (AND THE SECURITIES ISSUED
UPON CONVERSION OR EXERCISE HEREOF) HAVE NOT BEEN
<PAGE>

REGISTERED UNDER THE UNITED STATES SECURITIES ACT OF 1933, AS AMENDED (THE "U.S.
SECURITIES ACT") OR THE SECURITIES LAWS OF ANY STATE OF THE UNITED STATES. THE
HOLDER HEREOF, BY PURCHASING SUCH SECURITIES, AGREES FOR THE BENEFIT OF THE
COMPANY THAT SUCH SECURITIES MAY BE OFFERED, SOLD, PLEDGED OR OTHERWISE
TRANSFERRED ONLY (A) TO THE COMPANY, (B) OUTSIDE THE UNITED STATES IN ACCORDANCE
WITH RULE 903 or 904 OF REGULATION S UNDER THE U.S. SECURITIES ACT, IF
APPLICABLE (C) INSIDE THE UNITED STATES (1) PURSUANT TO THE EXEMPTION FROM THE
REGISTRATION REQUIREMENTS UNDER THE U.S. SECURITIES ACT PROVIDED BY RULE 144
THEREUNDER, IF AVAILABLE, AND IN ACCORDANCE WITH APPLICABLE STATE SECURITIES LAW
OR (2) IN A TRANSACTION THAT DOES NOT OTHERWISE REQUIRE REGISTRATION UNDER THE
U.S. SECURITIES ACT OR ANY APPLICABLE STATE SECURITIES LAW, PROVIDED THE HOLDER
HAS FURNISHED TO THE COMPANY AN OPINION OF COUNSEL OF RECOGNIZED STANDING TO
THAT EFFECT IN FORM AND SUBSTANCE, REASONABLY SATISFACTORY TO THE COMPANY, OR
(3) PURSUANT TO A REGISTRATION STATEMENT PURSUANT TO THE U.S. SECURITIES ACT.

               (b) THE HOLDER, BY ITS ACCEPTANCE OF THIS SECURITY, REPRESENTS,
ACKNOWLEDGES, AND AGREES THAT IT WILL NOT AND WILL NOT BE ENTITLED TO, DIRECTLY
OR INDIRECTLY, SELL OR TRANSFER THE SECURITIES INTO CANADA OR TO RESIDENTS OF
CANADA, EXPECT IN COMPLIANCE WITH APPLICABLE CANADIAN SECURITIES LAWS. NO SALE
OR TRANSFER INTO CANADA OR TO A CANADIAN RESIDENT WILL BE REGISTERED BY WORLD
HEART CORPORATION'S TRANSFER AGENT AND ANY ATTEMPT TO EFFECT SUCH A TRANSFER IS
INVALID UNLESS MADE IN COMPLIANCE WITH THE ABOVE-NOTED RESTRICTIONS. UNLESS
PERMITTED UNDER CANADIAN SECURITIES LEGISLATION, THE HOLDER OF THE SECURITIES
SHALL NOT TRADE THE SECURITIES BEFORE [FOUR MONTHS PLUS ONE DAY FROM THE DATE OF
ISSUANCE].

               (c) THE COMMON SHARES UNDERLYING THE WARRANTS OR THE DEBENTURES
REPRESENTED BY THIS CERTIFICATE ARE LISTED ON THE TORONTO STOCK EXCHANGE;
HOWEVER, THE SAID SECURITIES CAN NOT BE TRADED THROUGH THE FACILITIES OF SUCH
EXCHANGE SINCE THEY ARE NOT FREELY TRANSFERABLE, AND CONSEQUENTLY ANY
CERTIFICATE REPRESENTING SUCH SECURITIES IS NOT "GOOD DELIVERY" IN SETTLEMENT OF
TRANSACTIONS ON THE TORONTO STOCK EXCHANGE.

               (d) If required by the authorities of any state in connection
with the issuance of sale of the Securities, the legend required by such state
authority.

               (e) Upon the earlier of (i) registration for resale pursuant to
the Registration Rights Agreement and receipt by the Company of the Investor's
written confirmation that such Securities will not be disposed of except in
compliance with the prospectus delivery requirements of the 1933 Act or (ii)
Rule 144(k) becoming available the
<PAGE>

Company shall, upon an Investor's written request, promptly cause certificates
evidencing the Securities to be replaced with certificates which do not the
restrictive legend set forth in paragraph (a) above and Debenture Shares and
Warrant Shares subsequently issued upon the due conversion of the Debentures or
the due exercise of the Warrants, respectively, to not bear the restrictive
legends under Section 5.7(a) provided the provisions of either clause (i) or
clause (ii) above, as applicable, are satisfied with respect to such Debenture
Shares and Warrant Shares. From and after the anniversary of four months and one
day of the Closing, the Company shall, upon an Investor's written request,
promptly cause certificates evidencing the Securities to be replaced with
certificates which do not the restrictive legend set forth in paragraphs (b)
and (c) above and Debenture Shares and Warrant Shares subsequently issued upon
due conversion of the Debentures or due exercise of the Warrants, respectively,
to not bear such the restrictive legends under Sections 5.7(b) and 5.7(c).
Whenever the Company is required to cause unlegended certificates to replace
previously issued legended certificates, if unlegended certificates are not
delivered to an Investor within three (3) Business Days of submission by that
Investor of legended certificate(s) to the Company's transfer agent together
with a representation letter in customary form, the Company shall be solely
responsible for, and shall indemnify the Investor from and against, any and all
Losses (as defined in Section 8.2) (including any Losses resulting from any
buy-in effected by or for the Investor's account) incurred by that Investor as a
result of such delay, and will pay or reimburse such Investor for such Losses
upon demand.

          5.8 Notation on Records. The Investor consents to the Company making a
notation on its records or giving instructions to any transfer agent of the
Securities in order to implement the restrictions on transfer set forth and
described herein.

          5.9 Accredited Investor. The Investor is an accredited investor as
defined in Rule 501(a) of Regulation D, as amended, under the 1933 Act.

          5.10 Prohibited Transactions. During the last thirty (30) days prior
to the date hereof, neither such Investor nor any Affiliate of such Investor
which (x) had knowledge of the transactions contemplated hereby, (y) has or
shares discretion relating to such Investor's investments or trading or
information concerning such Investor's investments, including in respect of the
Securities, or (z) is subject to such Investor's review or input concerning such
Affiliate's investments or trading (collectively, "Trading Affiliates") has,
directly or indirectly, effected or agreed to effect any short sale, whether or
not against the box, established any "put equivalent position" (as defined in
Rule 16a-1(h) under the 1934 Act) with respect to the Common Stock, granted any
other right (including, without limitation, any put or call option) with respect
to the Common Stock or with respect to any security that includes, relates to or
derived any significant part of its value from the Common Stock or otherwise
sought to hedge its position in the Securities (each, a "Prohibited
Transaction"). Prior to the earliest to occur of (i) the termination of this
Agreement, (ii) the Effective Date or (iii) the Effectiveness Deadline, such
Investor shall not, and shall cause its Trading Affiliates not to, engage,
directly or indirectly, in a Prohibited Transaction. Such Investor acknowledges
that the representations, warranties and covenants contained in this Section
5.10 are being made for the benefit of the Investors as well as the Company and
that each of the other Investors shall have an independent right to assert any
claims against such Investor arising out of any breach or violation of the
provisions of this Section 5.10.
<PAGE>

          5.11 Toronto Stock Exchange. The Investor has completed and duly
signed a copy of the Private Placement Questionnaire and Undertaking required
by the TSX attached hereto as Exhibit E_;

          5.12 No General Solicitation or General Advertising. The Investor did
not learn of the investment in the Securities as a result of any general
solicitation or general advertising (as those terms are used in Regulation D
under the 1933 Act).

          5.13 Brokers and Finders. No Person will have, as a result of the
transactions contemplated by this Agreement, any valid right, interest or claim
against or upon the Company, any Subsidiary or an Investor for any commission,
fee or other compensation pursuant to any agreement, arrangement or
understanding entered into by or on behalf of the Investors.

          5.14 Foreign Issuer. The Investor understands and acknowledges that
the Company is not obligated to remain a "foreign issuer" within the meaning of
Regulation S under the 1933 Act.

          5.15 Securities Filings. Each Investor will provide to the Company
upon its reasonable request from time to time such information about the
Investor and its ownership of the Company's securities as the Company is
required to include in its proxy statement, annual report or current reports
filed with the SEC or its information circular, annual information form or
material change reports filed with TSX or Canadian securities regulators."

     6.   Conditions to Closing.
          ---------------------

          6.1 Conditions to the Investors' Obligations. The obligation of the
Investors to purchase the Debentures and the Warrants at the Closing is subject
to the fulfillment to the Investors' satisfaction, on or prior to the Closing
Date, of the following conditions, any of which may be waived by the Investors
agreeing hereunder to purchase a majority of the Debentures and the Warrants
(the "Required Investors"):

              (a) The representations and warranties made by the Company in
Section 4 hereof qualified as to materiality shall be true and correct at all
times prior to and on the Closing Date, except to the extent any such
representation or warranty expressly speaks as of an earlier date, in which case
such representation or warranty shall be true and correct as of such earlier
date, and, the representations and warranties made by the Company in Section 4
hereof not qualified as to materiality shall be true and correct in all material
respects at all times prior to and on the Closing Date, except to the extent any
such representation or warranty expressly speaks as of an earlier date, in which
case such representation or warranty shall be true and correct in all material
respects as of such earlier date. The Company shall have performed in all
material respects all obligations and conditions herein required to be performed
or observed by it on or prior to the Closing Date.
<PAGE>

              (b) The Company shall have obtained in a timely fashion any and
all consents, permits, approvals, registrations and waivers (including, without
limitation, any required approval of the TSX and NASDAQ) necessary or
appropriate for consummation of the purchase and sale of the Securities and the
consummation of the other transactions contemplated hereby, all of which shall
be in full force and effect.

              (c) The Company shall have entered into one or more subscription
agreements with investors located in Canada that contain terms no more
favourable to the subscriber than the terms of this Agreement (the "Other
Agreements").

              (d) The Company shall have received gross proceeds from the sale
of the Debentures and the Warrants as contemplated hereby and under the Other
Agreements of at least US$12 million.

              (e) The Company shall have executed and delivered the
Registration Rights Agreement and the Company and the warrant agent shall have
executed and delivered the Warrant Indenture.

              (f) No judgment, writ, order, injunction, award or decree of or
by any court, or judge, justice or magistrate, including any bankruptcy court or
judge, or any order of or by any governmental authority, shall have been issued,
and no action or proceeding shall have been instituted by any governmental
authority, enjoining or preventing the consummation of the transactions
contemplated hereby or in the other Transaction Documents.

              (g) The Company shall have delivered a Certificate, executed on
behalf of the Company by its Chief Executive Officer or its Chief Financial
Officer, dated as of the Closing Date, certifying to the fulfillment of the
conditions specified in subsections (a), (b), (c), (d) and (j) of this Section
6.1.

              (h) The Company shall have delivered a Certificate, executed on
behalf of the Company by its Secretary, dated as of the Closing Date, certifying
the resolutions adopted by the Board of Directors of the Company approving the
transactions contemplated by this Agreement and the other Transaction Documents
and the issuance of the Securities, certifying the current versions of the
articles of incorporation and bylaws of the Company and certifying as to the
signatures and authority of persons signing the Transaction Documents and
related documents on behalf of the Company.

              (i) The Investors shall have received opinions from White & Case
LLP and McCarthy Tetrault LLP, the Company's counsel, dated as of the Closing
Date, in form and substance reasonably acceptable to the Investors and
addressing such legal matters as the Investors may reasonably request.

              (j) No stop order or suspension of trading shall have been
imposed by the TSX or NASDAQ, the SEC or any other governmental regulatory body
with respect to public trading in the Common Stock.
<PAGE>

          6.2 Conditions to Obligations of the Company. The Company's obligation
to sell and issue the Debentures and the Warrants at the Closing is subject to
the fulfillment to the satisfaction of the Company on or prior to the Closing
Date of the following conditions, any of which may be waived by the Company:

               (a) The representations and warranties made by the Investors in
Section 5 hereof, other than the representations and warranties contained in
Sections 5.3, 5.4, 5.5, 5.6, 5.7, 5.8 and 5.10 (the "Investment
Representations"), shall be true and correct in all material respects when made,
and shall be true and correct in all material respects on the Closing Date with
the same force and effect as if they had been made on and as of said date. The
Investment Representations shall be true and correct in all respects when made,
and shall be true and correct in all respects on the Closing Date with the same
force and effect as if they had been made on and as of said date. The Investors
shall have performed in all material respects all obligations and conditions
herein required to be performed or observed by them on or prior to the Closing
Date.

               (b) The Investors shall have delivered the Purchase Price to the
Company.

               (c) The Investors shall have executed and delivered the
Registration Rights Agreement.

               (d) The Company shall have obtained in a timely fashion any and
all consents, permits, approvals, registrations and waivers (including, without
limitation, any required approval of the TSX and NASDAQ) necessary or
appropriate for consummation of the purchase and sale of the Securities and the
consummation of the other transactions contemplated hereby, all of which shall
be in full force and effect.

          6.3 Termination of Obligations to Effect Closing; Effects.
              -----------------------------------------------------

              (a) The obligations of the Company, on the one hand, and the
Investors, on the other hand, to effect the Closing shall terminate as follows:

                  (i) Upon the mutual written consent of the Company and the
Required Investors;

                  (ii) By the Company if any of the conditions set forth in
Section 6.2 shall have become incapable of fulfillment, and shall not have been
waived by the Company;

                  (iii) By the Required Investors if any of the conditions set
forth in Section 6.1 shall have become incapable of fulfillment, and shall not
have been waived by the Required Investors; or

                  (iv) By the Required Investors if the Closing has not
occurred on or prior to October 31, 2004;
<PAGE>

provided, however, that, except in the case of clause (i) above, the party
seeking to terminate its obligation to effect the Closing shall not then be in
breach of any of its representations, warranties, covenants or agreements
contained in this Agreement or the other Transaction Documents if such breach
has resulted in the circumstances giving rise to such party's seeking to
terminate its obligation to effect the Closing.

              (b) In the event of termination by the Company or the Required
Investors of their obligations to effect the Closing pursuant to this Section
6.3, written notice thereof shall forthwith be given to the other parties hereto
and the obligation of all parties to effect the Closing shall be terminated,
without further action by any party. Nothing in this Section 6.3 shall be deemed
to release any party from any liability for any breach by such party of the
terms and provisions of this Agreement or the other Transaction Documents or to
impair the right of any party to compel specific performance by any other party
of its obligations under this Agreement or the other Transaction Documents.

     7.   Covenants and Agreements of the Company.
          ---------------------------------------

          7.1 Reservation of Common Stock. The Company shall at all times
reserve and keep available out of its authorized but unissued shares of Common
Stock, solely for the purpose of providing for the conversion of the Debentures
and the exercise of the Warrants, such number of shares of Common Stock as shall
from time to time equal the number of shares sufficient to permit the conversion
of the Debentures and the exercise of the Warrants issued pursuant to this
Agreement in accordance with their respective terms.

          7.2 Reports. The Company will furnish to such Investors and/or their
assignees such information relating to the Company and its Subsidiaries as from
time to time may reasonably be requested by such Investors and/or their
assignees; provided, however, that the Company shall not disclose material
nonpublic information to the Investors, or to advisors to or representatives of
the Investors, unless prior to disclosure of such information the Company
identifies such information as being material non-public information and
provides the Investors, such advisors and representatives with the opportunity
to accept or refuse to accept such material nonpublic information for review and
any Investor wishing to obtain such information enters into an appropriate
confidentiality agreement with the Company with respect thereto.

          7.3 No Conflicting Agreements. The Company will not take any action,
enter into any agreement or make any commitment that would conflict or interfere
in any material respect with the obligations to the Investors under the
Transaction Documents.

          7.4 Insurance. The Company shall not materially reduce the insurance
coverages described in Section 4.19.

          7.5 Compliance with Laws. The Company will comply in all material
respects with all applicable laws, rules, regulations, orders and decrees of all
governmental authorities.
<PAGE>

          7.6 Listing of Underlying Shares and Related Matters. Promptly
following the date hereof, the Company shall take all necessary action to cause
the Debenture Shares and the Warrant Shares to be listed, subject to issuance,
on the TSX and NASDAQ no later than the Closing Date. Further, if the Company
applies to have its Common Stock or other securities traded on any other
principal stock exchange or market, it shall include in such application the
Debenture Shares and the Warrant Shares and will take such other action as is
necessary to cause such Common Stock to be so listed. The Company will use
commercially reasonable efforts to continue the listing and trading of its
Common Stock on the TSX and NASDAQ and, in accordance, therewith, will use
commercially reasonable efforts to comply in all respects with the Company's
reporting, filing and other obligations under the bylaws or rules of such market
or exchange, as applicable.

          7.7 Termination of Covenants. The provisions of Sections 7.2 through
7.5 shall terminate and be of no further force and effect upon the earlier of
(i) mutual consent of the Company and the Required Investors or (ii) the date on
which the Company's obligations under the Registration Rights Agreement to
register or maintain the effectiveness of any registration covering the
Registrable Securities (as such term is defined in the Registration Rights
Agreement) shall terminate.

     8.   Survival and Indemnification.
          ----------------------------

          8.1 Survival. All representations, warranties, covenants and
agreements contained in this Agreement shall be deemed to be representations,
warranties, covenants and agreements as of the date hereof and shall survive the
execution and delivery of this Agreement for a period of two (2) years from the
date of this Agreement; provided, however, that the provisions contained in
Section 7 hereof shall survive in accordance therewith.

          8.2 Indemnification. The Company agrees to indemnify and hold harmless
each Investor and its Affiliates and their respective directors, officers,
employees and agents from and against any and all losses, claims, damages,
liabilities and expenses (including without limitation reasonable attorney fees
and disbursements and other expenses incurred in connection with investigating,
preparing or defending any action, claim or proceeding, pending or threatened
and the costs of enforcement hereof) (collectively, "Losses") to which such
Person may become subject as a result of any breach of representation, warranty,
covenant or agreement made by or to be performed on the part of the Company
under the Transaction Documents, and will reimburse any such Person for all such
amounts as they are incurred by such Person.

          8.3 Conduct of Indemnification Proceedings. Promptly after receipt by
any Person (the "Indemnified Person") of notice of any demand, claim or
circumstances which would or might give rise to a claim or the commencement of
any action, proceeding or investigation in respect of which indemnity may be
sought pursuant to Section 8.2, such Indemnified Person shall promptly notify
the Company in writing and the Company shall assume the defense thereof,
including the employment of counsel reasonably satisfactory to such Indemnified
Person, and shall assume the payment of all fees and expenses; provided,
however, that the failure of any Indemnified Person so to notify the Company
shall not relieve the Company of its obligations hereunder except to the extent
that the Company is materially
<PAGE>

prejudiced by such failure to notify. In any such proceeding, any Indemnified
Person shall have the right to retain its own counsel, but the fees and expenses
of such counsel shall be at the expense of such Indemnified Person unless: (i)
the Company and the Indemnified Person shall have mutually agreed to the
retention of such counsel; or (ii) in the reasonable judgment of counsel to such
Indemnified Person representation of both parties by the same counsel would be
inappropriate due to actual or potential differing interests between them. The
Company shall not be liable for any settlement of any proceeding effected
without its written consent, which consent shall not be unreasonably withheld,
but if settled with such consent, or if there be a final judgment for the
plaintiff, the Company shall indemnify and hold harmless such Indemnified Person
from and against any loss or liability (to the extent stated above) by reason of
such settlement or judgment. Without the prior written consent of the
Indemnified Person, which consent shall not be unreasonably withheld, the
Company shall not effect any settlement of any pending or threatened proceeding
in respect of which any Indemnified Person is or could have been a party and
indemnity could have been sought hereunder by such Indemnified Party, unless
such settlement includes an unconditional release of such Indemnified Person
from all liability arising out of such proceeding.

     9.   Miscellaneous.
          -------------

          9.1 Successors and Assigns. This Agreement may not be assigned by a
party hereto without the prior written consent of the Company or the Required
Investors, as applicable, provided, however, that an Investor may assign its
rights and delegate its duties hereunder in whole or in part to an Affiliate or
to a third party acquiring some or all of its Securities in a private
transaction without the prior written consent of the Company or the other
Investors, after notice duly given by such Investor to the Company and the other
Investors, provided, that no such assignment or obligation shall affect the
obligations of such Investor hereunder. The provisions of this Agreement shall
inure to the benefit of and be binding upon the respective permitted successors
and assigns of the parties. Nothing in this Agreement, express or implied, is
intended to confer upon any party other than the parties hereto or their
respective successors and assigns any rights, remedies, obligations, or
liabilities under or by reason of this Agreement, except as expressly provided
in this Agreement.

          9.2 Counterparts; Faxes. This Agreement may be executed in two or more
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument. This Agreement may also
be executed via facsimile, which shall be deemed an original.

          9.3 Titles and Subtitles. The titles and subtitles used in this
Agreement are used for convenience only and are not to be considered in
construing or interpreting this Agreement.

          9.4 Notices. Unless otherwise provided, any notice required or
permitted under this Agreement shall be given in writing and shall be deemed
effectively given as hereinafter described (i) if given by personal delivery,
then such notice shall be deemed given upon such delivery, (ii) if given by
telex or telecopier, then such notice shall
<PAGE>

be deemed given upon receipt of confirmation of complete transmittal, (iii) if
given by mail, then such notice shall be deemed given upon the earlier of (A)
receipt of such notice by the recipient or (B) three days after such notice is
deposited in first class mail, postage prepaid, and (iv) if given by an
internationally recognized overnight air courier, then such notice shall be
deemed given one day after delivery to such carrier. All notices shall be
addressed to the party to be notified at the address as follows, or at such
other address as such party may designate by ten days' advance written notice to
the other party:

                  If to the Company:

                            1 Laser Street
                            Ottawa, Ontario Canada
                            K2E 7V1
                            Attention:  Chief Financial Officer
                            Fax:  (613) 226-4744

                  With a copy to:

                            McCarthy Tetrault LLP
                            Suite 1400
                            40 Elgin Street
                            Ottawa, Ontario
                            K1P 5K6
                            Attention:  Virginia K. Schweitzer, Esq.
                            Fax:  (613) 563-9386

                  If to the Investors:

to the addresses set forth on the signature pages hereto.

          9.5 Expenses. The parties hereto shall pay their own costs and
expenses in connection herewith, except that the Company shall pay the
reasonable fees and expenses of counsel to the Investors, not to exceed a total
aggregate amount of $25,000 for all Investors. Such expenses shall be paid not
later than the Closing. The Company shall reimburse the Investors upon demand
for all reasonable out-of-pocket expenses incurred by the Investors, including
without limitation reimbursement of attorneys' fees and disbursements, in
connection with any amendment, modification or waiver of this Agreement or the
other Transaction Documents. In the event that legal proceedings are commenced
by any party to this Agreement against another party to this Agreement in
connection with this Agreement or the other Transaction Documents, the party or
parties which do not prevail in such proceedings shall severally, but not
jointly, pay their pro rata share of the reasonable attorneys' fees and other
reasonable out-of-pocket costs and expenses incurred by the prevailing party in
such proceedings.

          9.6 Amendments and Waivers. Any term of this Agreement may be amended
and the observance of any term of this Agreement may be waived (either generally
or in a particular instance and either retroactively or prospectively), only
with the written consent of the

<PAGE>

Company and the Required Investors. Any amendment or waiver effected in
accordance with this paragraph shall be binding upon each holder of any
Securities purchased under this Agreement at the time outstanding, each future
holder of all such securities, and the Company.

          9.7 Publicity. No public release or announcement concerning the
transactions contemplated hereby shall be issued by the Company or the Investors
without the prior consent of the Company (in the case of a release or
announcement by the Investors), or Special Situations Fund III, L.P. ("SSF") (in
the case of a release or announcement by the Company) (which consents shall not
be unreasonably withheld), except as such release or announcement may be
required by law or the applicable rules or regulations of any securities
exchange or securities market, in which case the Company or the Investors, as
the case may be, shall allow SSF or the Company, as applicable, to the extent
reasonably practicable in the circumstances, reasonable time to comment on such
release or announcement in advance of such issuance.

          9.8 Severability. Any provision of this Agreement that is prohibited
or unenforceable in any jurisdiction shall, as to such jurisdiction, be
ineffective to the extent of such prohibition or unenforceability without
invalidating the remaining provisions hereof but shall be interpreted as if it
were written so as to be enforceable to the maximum extent permitted by
applicable law, and any such prohibition or unenforceability in any jurisdiction
shall not invalidate or render unenforceable such provision in any other
jurisdiction. To the extent permitted by applicable law, the parties hereby
waive any provision of law which renders any provision hereof prohibited or
unenforceable in any respect.

          9.9 Entire Agreement. This Agreement, including the Exhibits and the
Disclosure Schedules, and the other Transaction Documents constitute the entire
agreement among the parties hereof with respect to the subject matter hereof and
thereof and supersede all prior agreements and understandings, both oral and
written, between the parties with respect to the subject matter hereof and
thereof.

          9.10 Further Assurances. The parties shall execute and deliver all
such further instruments and documents and take all such other actions as may
reasonably be required to carry out the transactions contemplated hereby and to
evidence the fulfillment of the agreements herein contained.

          9.11 Governing Law; Consent to Jurisdiction; WAIVER OF JURY TRIAL.
This Agreement shall be governed by, and construed in accordance with, the
internal laws of the State of New York without regard to the choice of law
principles thereof. Each of the parties hereto irrevocably submits to the
exclusive jurisdiction of the courts of the State of New York located in New
York County and the United States District Court for the Southern District of
New York for the purpose of any suit, action, proceeding or judgment relating to
or arising out of this Agreement and the transactions contemplated hereby.
Service of process in connection with any such suit, action or proceeding may be
served on each party hereto anywhere in the world by the same methods as are
specified for the giving of notices under this Agreement. Each of the parties
hereto irrevocably consents to the jurisdiction of any such court in any such
suit, action or proceeding and to the laying of venue in such court. Each party
hereto irrevocably waives any objection to the laying of venue of any such suit,
action or proceeding brought in such courts and
<PAGE>

irrevocably waives any claim that any such suit, action or proceeding brought in
any such court has been brought in an inconvenient forum. EACH OF THE PARTIES
HERETO WAIVES ANY RIGHT TO REQUEST A TRIAL BY JURY IN ANY LITIGATION WITH
RESPECT TO THIS AGREEMENT AND REPRESENTS THAT COUNSEL HAS BEEN CONSULTED
SPECIFICALLY AS TO THIS WAIVER.

          9.12 Independent Nature of Investors' Obligations and Rights. The
obligations of each Investor under any Transaction Document are several and not
joint with the obligations of any other Investor, and no Investor shall be
responsible in any way for the performance of the obligations of any other
Investor under any Transaction Document. The decision of each Investor to
purchase Securities pursuant to the Transaction Documents has been made by such
Investor independently of any other Investor. Nothing contained herein or in any
Transaction Document, and no action taken by any Investor pursuant thereto,
shall be deemed to constitute the Investors as a partnership, an association, a
joint venture or any other kind of entity, or create a presumption that the
Investors are in any way acting in concert or as a group with respect to such
obligations or the transactions contemplated by the Transaction Documents. Each
Investor acknowledges that no other Investor has acted as agent for such
Investor in connection with making its investment hereunder and that no Investor
will be acting as agent of such Investor in connection with monitoring its
investment in the Securities or enforcing its rights under the Transaction
Documents. Each Investor shall be entitled to independently protect and enforce
its rights, including, without limitation, the rights arising out of this
Agreement or out of the other Transaction Documents, and it shall not be
necessary for any other Investor to be joined as an additional party in any
proceeding for such purpose. The Company acknowledges that each of the Investors
has been provided with the same Transaction Documents for the purpose of closing
a transaction with multiple Investors and not because it was required or
requested to do so by any Investor.

                            [signature page follows]

<PAGE>
          IN WITNESS WHEREOF, the parties have executed this Agreement or caused
their duly authorized officers to execute this Agreement as of the date first
above written.

The Company:                WORLD HEART CORPORATION



                            By:
                               ----------------------
                            Name:
                            Title:
<PAGE>


The Investor:





                            By:
                               ----------------------
                            Name:
                            Title:

Aggregate Purchase Price:  US$___________________________________

Address for Notice:
                                                ------------------------------

                                                ------------------------------

                                                ------------------------------


                                                with a copy to, if any:


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