Andersons pediatric cardiology 1379
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childhood.Themajorityaresarcomas.1Theyarecharacterizedclinicallybya
rapidlydownhillcourse,withdeathoccurringshortlyfollowingtheonsetof
symptoms.Thisiscausedbytherapidgrowthofthetumor,systemic
dissemination,andunfavorableresponsetomedicalorsurgicaltreatment.1,128
Thetumorshaveatendencytoinvadethemyocardiumandtoextendwithinthe
cardiacchambers.Theyaredifficulttoexcisecompletely.129Metastasistothe
lungs,thymus,andregionallymphnodescanoccur.1Early,aggressivesurgical
excision,mostofteninconjunctionwithadjunctivechemotherapyandradiation
therapy,mightresultinlongersurvivalinsomepatients.1,106,130Thisapproach,
nonetheless,remainspalliativebecausemalignanttumorsarealmostinvariably
fatal.1,130Cardiactransplantationhasbeenperformedinalimitednumberof
patientswithinconsistentresults.106,131
SecondaryCardiacTumors
Thesearealsoveryrareinchildrenbutaremorefrequentthantheprimarytype.
Theclinicalpictureisnearlyalwaysdominatedbytheunderlyingdisease,albeit
thatoccasionallythecardiacsymptomsconstitutethebasisforthepresenting
complaints.Cardiacinvolvementoccurssecondarytoeitherdirectextension,
hematogenousorlymphaticspread,orviaextensionfromtheinferiorcaval
vein.3Lymphomaisthemostcommonunderlyingdiseaseinchildren,followed
byWilmstumor.Othersolidneoplasms,suchasmalignanthepatictumor,may
alsometastasizeorgrowintotheheart.132,133Thesymptomsproducedbythe
metastaticlesionsdependonthesiteandextentofthetumor.Pericardial
involvementmaygiverisetopericardialeffusion,whichisoftenbloodstained.
Cardiaccompressionmaybecausedbyeitheraneffusionorasolidtumor
encasingtheheart.Postoperativeoutcomeinpatientswithsecondarycardiac
tumorsispoor.Thussurgeryshouldbereservedforcaseswithhemodynamic
compromise.132
SurgicalTherapy
Theplanningofsurgicaltreatmentmustbebasedontheaccurateassessmentof
thenumber,location,size,andextentofthetumor(s)onthehemodynamicstate
ofthepatientandonthehistologicnatureofthelesion.Noninvasiveimaging
generallyprovidesmost,ifnotall,ofthisinformation.Althoughendomyocardial
biopsyhasbeenpromotedasameansofhistologicdiagnosis,inmostcasesthe
histologicnatureofthetumormaybepredictedaccuratelyfromthenoninvasive
investigations.Ininfants,multiplenodulesnearlyalwayspointtoa
rhabdomyoma,byfarthemostcommontumoroftheheartseeninchildren.The
presenceoftuberoussclerosisintheinfant,orinthefamily,confirmsthe
diagnosis.Alargeandwell-circumscribedtumorintheseptumorventricular
wallislikelytobeafibromaoranintracardiacteratoma.
Becauseofadvancesincardiacsurgery,completeresectionofvirtuallyall
primarycardiactumorsiscurrentlypossible.130Asaresult,theprognosisof
childrenwithprimarycardiactumorshasimprovedsignificantlyinrecent
decades.AEuropeanmulticenteranalysisofsurgicalresultsin89primarytumor
cases(includingfourcardiactransplants)foundanearlyandlatemortalityrate
of4.5%forallpatients.134Ifonlybenigntumorswereconsidered,early
mortalitydecreasedto2.4%.Mortalitywasthoughttobedirectlyduetothe
operationinonlyonepatientwithanextensiveextracardiacteratoma.The
remainderofdeathswereattributedprimarilytomalignancyandnoncardiac
complications.Fourpatientsrequiredreoperationforatrioventricularvalve
dysfunction,andtwopatientsrequiredresectionofrecurrentmyxomas.Inthe
Bostonexperience,62patientsunderwentsurgicalresectionofprimarytumors,
withsurgicaldeathsinthreepatientsduetodamagetosurroundingstructures.5
Threeinfantsdevelopedlargeleftventricularaneurysmsatthesiteofresection,
oneofwhichrequiredsurgicalreduction.Onepatientdevelopedcompleteheart
block.InaseriesfromIndianapolisthatincluded30patientswhounderwent
surgery,therewasnosurgicalmortalityforbenigntumorsbut38%mortalityfor
malignanttumors(bothprimaryandsecondary).Postoperativecardiac
complicationsweremostlylimitedtomitralregurgitationnotrequiringsurgical
reintervention.135
Ingeneral,surgicalresectionisindicatedinthefollowingpopulations:
1.Symptomaticpatients
2.Patientswithsignificantobstructionofeithertheventricularinletor
outlet
3.Patientswithlife-threateningarrhythmias76
Thepotentialforspontaneousormedicallyinducedregressionof
rhabdomyomasandinfantilehemangiomasshouldbetakenintoaccount.112
Singlelesionsamenabletosurgicalresection,especiallyfibromas,shouldbe
consideredforremovalbecauseofthepossibilityofarrhythmias,andeven
suddencardiacdeath.Ingeneral,theaimiscompleteresection.However,in
manyseries,incompleteresectionofbenigntumorshasledtogoodresults
withouttumororarrhythmiarecurrenceandmaybepreferableincaseswhere
completeresectionmayremoveexcessivemyocardiumorcausedamageto
nearbystructures.5,130,134,136Hearttransplantationhasbeenperformedincases
withextensivemyocardialinvolvement;however,thisshouldbeconsideredin
thelightoftheefficacyofpartialresection.Inthesettingofmyxomas,surgery
shouldbeundertakenurgentlybecauseofthepotentialforcatastrophic
embolization.Carefulexaminationoftheentireheartisnecessarytoremove
concurrentsitesofmyxomatoustissue.
