Andersons pediatric cardiology 1377
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areheterogeneouswithsolidandmulticysticareasandcalcifications(Fig.
52.16).Pericardialeffusionsarenearlyalwaysseenandmaybelargeand
hemodynamicallysignificant.MRIandCTcanbehelpfulindeterminingthe
extentandvascularizationofthetumor.
FIG.52.16 (A)Pericardialteratoma(asterisk)inanewborn.(B)Sagittal
view.Notetheveryheterogeneousappearanceofthetumor,aswellthe
associatedpericardialeffusion(dagger).
Teratomasareoftendiagnosedinfetallife,particularlyduetopericardial
effusions.Hydropsmaybepresentandtendstoberapidlyprogressive.Infants
frequentlypresentwithtamponadeandcardiovascularcollapse.Cyanosis,
respiratorydistress,andstillbirthhavealsobeendescribed.1Teratomastendto
growrapidlyandmayreachbizarredimensions,leadingtoimpairedcardiac
functionwithorwithoutcongestivecardiacfailureortocompressionofthe
airwayswithrespiratorydistress.Suddendeaths,severeencroachmentbythe
tumorontheheartandgreatvessels,andinfectiouspericarditishaveallbeen
reported.97
Earlyandaccuratediagnosisisofparamountimportanceinsuchcriticallyill
patientsbecausesurgicalexcisionanddecompressionofthepericardialeffusion
canbeachievedsuccessfully.Furthermore,diagnosisduringfetallifeallows
promptpostnatal,orevenprenatal,interventiontothedevelopmentof
cardiopulmonarydistress.49,50,52,53,111Inolder,asymptomaticchildren,surgical
removalofthetumorisrecommendedbecauseoftheriskofsuddendeathand
potentialformalignanttransformation.
VascularTumors
Vascularprimarycardiactumorsrepresentaheterogeneousgroupandcanhave
variouspathologiccharacteristics.112Thetermhemangiomahassometimesbeen
usedasagenerictermtorepresentvarioustypesofvasculartumors.Vascular
tumorsarisingfromtheheartareextremelyrare,havingbeendocumentedinless
than10%ofallprimarycardiactumorsseeninchildren.99
Vasculartumorshavebeendescribedinallcardiacchambersandcanbe
intracavitary,myocardial,epicardial,orpericardial.1Tumortype,clinical
presentation,andprognosistendtovarywiththepatient'sageatpresentation.
Fetalandinfantiletumorstendtobemorefrequentlyrightatrialand
symptomatic.Mostareassociatedwithpericardialeffusionsandcanpresentwith
tamponade.Thesetumorsmayregressspontaneouslyandmayrespondto
antiangiogenicmedicationsuchascorticosteroidsandinterferon-α.Incontrast,
tumorsthatpresentafterthefirstyearoflifetendtobelessrightsidedandmay
beintramyocardial.Thesetumorsaregenerallyasymptomaticanddonot
spontaneouslyregressorrespondtomedication.Otherreportedsignsand
symptomsincludecongestiveheartfailure,valvardisease,outflowtract
obstruction,andatrioventricularblock.
Grossinspectionwillusuallyreadilyidentifythetruenatureofthelesion.On
histology,variousvascularlesionscanbefoundandarediagnosedbasedonthe
predominantsizeofthevesselsinvolved,withthemostcommondescribedas
capillaryandcavernoustypes.1,31Veryrarely,vasculartumorsmaybe
malignant.
Onechocardiographytheselesionsareheterogeneousandcanhavecystic
spaces(Fig.52.17).ColorDopplerinterrogationmayrevealvascularchannels
withinthelesion,althoughthesearenotalwayspresent.74MRImaybeusedto
characterizetumortypeandextentofthelesionandtoquantifyhemodynamic
burden.CharacteristicfindingsonMRIarehyperintensityonT2-weighted
sequencesandavidenhancementonfirstpassperfusionaftergadolinium
administration.Differentiationfrommalignantvasculartumorsmaybedifficult,
andfactorssuchasill-definedboundaries,crossingoftissueplaneswithinthe
heart,andclinicalpresentationshouldbeconsidered.54,113
FIG.52.17 (A)Vasculartumor(asterisks)inanewbornsurroundingthe
superiorvenacava.Notelackofcolorflowturbulenceinthesuperiorvena
cavaaswellasanassociatedpericardialeffusion(dagger).(B)Vascular
tumor(asterisk)ina4-year-oldlocatedwithintheleftventricular
myocardium.Notecolorflowwithinthetumor.
Aswithrhabdomyomas,nonsurgicalmanagementispreferredininfancy
becausethesetumorsmayinvolutespontaneouslyorwithmedication.Infantile
tumorsalsomayrecuraftersurgicalresection.Incontrast,symptomatictumors
inolderchildrenshouldberesected,andtheytendnottorecur.112
Lipomas
Anotherveryraretypeofpediatrictumor,cardiaclipomasarebenign
encapsulatedlesionscomposedofmatureadiposecells.Lipomasaregenerally
solitary,althoughMFFoftuberoussclerosisarefrequentlymultiple(seeearlier).
Theycanpresentinanylocation,mostcommonlytherightatriumandleft
ventricle.Mosttumorsaresubepicardialorsubepicardial,althoughtheycanalso
beintramural.114Lipomasaregenerallyasymptomaticanddiscovered
incidentally,althoughtherearereportsofarrhythmiaandevensuddendeathin
adults.Surgicalresectioncanbeperformedwithgoodresultsandisreservedfor
symptomaticpatients.115Onechocardiographythelesionsarehomogenousand
havebeendescribedasbothhyperechogenicandhypoechogenic.116OnMRI,
fattylesionshaveacharacteristicchemicalshiftartifactonbrightbloodimages.
TheyarehyperintenseonT1-weightedimages,withasignificantdecreasein
signalwhenfatsuppressionisadded.OnCT,thesemasseshaveacharacteristic
lowattenuationsimilartoepicardialandmediastinalfat.
