-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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 ew5L1rwEizfHOzsxhd0Faw==

<SEC-DOCUMENT>0001179110-10-005820.txt : 20100322
<SEC-HEADER>0001179110-10-005820.hdr.sgml : 20100322
<ACCEPTANCE-DATETIME>20100322172655
ACCESSION NUMBER:		0001179110-10-005820
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100318
FILED AS OF DATE:		20100322
DATE AS OF CHANGE:		20100322

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:		10697444

	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>2010-03-18</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>2010-03-18</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>10310</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>2.47</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2531021</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Shares</value>
            </securityTitle>
            <transactionDate>
                <value>2010-03-19</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>23925</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>2.25</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2507096</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">The weighted average price of 2.47 is a result of the following sales of shares: 200 at 2.55, 200 at 2.54, 150 at 2.53, 300 at 2.51, 3086 at 2.50, 200 at 2.47, 5864 at 2.45, 100 at 2.41 and 210 at 2.40</footnote>
        <footnote id="F2">The weighted average price of 2.25 is a result of the following sales of shares: 100 at 2.34, 10000 at 2.30, 200 at 2.28, 1100 at 2.26, 8600 at 2.25, 3925 at 2.14</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Ian W. McLeod, Corporate Controller</signatureName>
        <signatureDate>2010-03-22</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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