<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2006-04-04</periodOfReport>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0001166463</issuerCik>
        <issuerName>VISICU INC</issuerName>
        <issuerTradingSymbol>EICU</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001352878</rptOwnerCik>
            <rptOwnerName>Sabin Ralph C</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O PACIFIC VENTURE GROUP</rptOwnerStreet1>
            <rptOwnerStreet2>114 PACIFICA, SUITE 270</rptOwnerStreet2>
            <rptOwnerCity>IRVINE</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92618</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>50000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Series B Convertible Preferred Stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F3"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F2"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>2189781</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote</value>
                    <footnoteId id="F4"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Series C Convertible Preferred Stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F3"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F2"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>729928</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote</value>
                    <footnoteId id="F5"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Immediately following the closing of the intitial public offering of the Issuer's Common Stock, all outstanding shares of Series B Convertible Preferred Stock and Series C Convertible Preferred Stock will be automatically converted into shares of the Issuer's Commmon Stock.</footnote>
        <footnote id="F2">Not Applicable.</footnote>
        <footnote id="F3">One share of Preferred Stock (including any of Series B Convertible Preferred Stock and Series C Convertible Preferred Stock) is convertible into one share of the Issuer's Common Stock.</footnote>
        <footnote id="F4">Includes 2,125,288 shares held by Pacific Venture Group II, L.P. and 64,493 shares held by PVG Associates II, L.P. PVG Equity Partners II, L.L.C. (&quot;PEP II&quot;) is the general partner of Pacific Venture Group II, L.P. and PVG Associates II, L.P.  Reporting Person is a director of the Issuer and the managing member of PEP II.  In his capacity as managing member of PEP II, the Reporting Person may be deemed a beneficial owner of the securities.  The Reporting Person expressly disclaims beneficial ownership of the securities except to the extent of his pecuniary interest therein.</footnote>
        <footnote id="F5">Includes 708,430 shares held by Pacific Venture Group II, L.P. and 21,498 shares held by PVG Associates II, L.P. PEP II is the general partner of Pacific Venture Group II, L.P. and PVG Associates II, L.P.  The Reporting Person is a director of the Issuer and the managing member of PEP II.  In his capacity as managing member of PEP II, the Reporting Person may be deemed a beneficial owner of the securities.  The Reporting Person expressly disclaims beneficial ownership of the securities except to the extent of his pecuniary interest therein, if any.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/S/ Gary Sindler, Attorney-in-fact</signatureName>
        <signatureDate>2006-04-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
