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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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<SEC-DOCUMENT>0001179110-10-005962.txt : 20100324
<SEC-HEADER>0001179110-10-005962.hdr.sgml : 20100324
<ACCEPTANCE-DATETIME>20100324165351
ACCESSION NUMBER:		0001179110-10-005962
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100322
FILED AS OF DATE:		20100324
DATE AS OF CHANGE:		20100324

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			WORLD HEART CORP
		CENTRAL INDEX KEY:			0001024520
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTROMEDICAL & ELECTROTHERAPEUTIC APPARATUS [3845]
		IRS NUMBER:				000000000
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		4750 WILEY POST WAY
		STREET 2:		SUITE 120
		CITY:			SALT LAKE CITY
		STATE:			UT
		ZIP:			84116
		BUSINESS PHONE:		801-355-6255

	MAIL ADDRESS:	
		STREET 1:		4750 WILEY POST WAY
		STREET 2:		SUITE 120
		CITY:			SALT LAKE CITY
		STATE:			UT
		ZIP:			84116

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ABIOMED INC
		CENTRAL INDEX KEY:			0000815094
		STANDARD INDUSTRIAL CLASSIFICATION:	SURGICAL & MEDICAL INSTRUMENTS & APPARATUS [3841]
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0331

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-28882
		FILM NUMBER:		10702269

	BUSINESS ADDRESS:	
		STREET 1:		22 CHERRY HILL DR
		CITY:			DANVERS
		STATE:			MA
		ZIP:			01923
		BUSINESS PHONE:		9787775410

	MAIL ADDRESS:	
		STREET 1:		22 CHERRY HILL DRIVE
		CITY:			DANVERS
		STATE:			MA
		ZIP:			01923
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 4 -
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-03-22</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001024520</issuerCik>
        <issuerName>WORLD HEART CORP</issuerName>
        <issuerTradingSymbol>WHRT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0000815094</rptOwnerCik>
            <rptOwnerName>ABIOMED INC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>22 CHERRY HILL DR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>DANVERS</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>01923</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Shares</value>
            </securityTitle>
            <transactionDate>
                <value>2010-03-22</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>22727</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>2.07</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2484369</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Shares</value>
            </securityTitle>
            <transactionDate>
                <value>2010-03-23</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>541799</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>2.69</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1942570</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">The weighted average price of 2.07 is a result of the following sales of shares: 3200 at 2.10, 5100 at 2.08, 4800 at 2.07, 800 at 2.06, and 8827 at 2.05.</footnote>
        <footnote id="F2">This price represents the weighted average purchase price of multiple transactions on the reported date: (i) 13,500 shares at prices between $2.90 and $3.00, (ii) 42,003 shares at prices between $2.80 and $2.89, (iii) 374,352 shares at prices between $2.70 and $2.79, (iv) 12,214 shares at prices between $2.60 and $2.69, (v) 45,000 shares at prices between $2.50 and $2.59, and (vi) 54,730 shares at prices between $2.40 and $2.49. All purchase data is available upon the Commission's request. Detailed information regarding the number of shares purchased at each separate price will be provided upon request by the Commission staff, the issuer, or a security holder of the issuer.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Ian W. McLeod, Corporate Controller</signatureName>
        <signatureDate>2010-03-24</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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