Andersons pediatric cardiology 1372
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field.
Prenatalechocardiographicscreening(Fig.52.7)haspermittedfetaltumorsto
bediagnosedasearlyas15weeksofgestation,withtwo-thirdsofthetumors
beingrhabdomyomas.1,49–51Priorknowledgeoftheexistenceofthetumorin
somecircumstanceshaspermittedlife-savinginterventions,suchasintrauterine
pericardiocentesisorevenintrauterinesurgery.Prenataldiagnosiscertainly
permitsoptimizationofpostnatalcare.1,49,50,52,53Spontaneousregressionofeven
symptomatictumorshasalsobeendescribedwhendiagnosedduringfetallife.1
FIG.52.7 Massiveright-sidedhearttumor(arrow)diagnosedduringfetal
echocardiographyat21weeksofgestation.Theneoplasm,whichis
primarilyextracardiac,mayhaveanintracardiacextension,andappearsto
havelimitedtheeffectiverightventricularcavity,causingsomeobstruction
oftherightventricularoutflowtract.Ateratomawassuspectedandwas
confirmedatpathology.(CourtesyDr.JuleneCarvalho,RoyalBrompton
Hospital,London,UnitedKingdom.)
MagneticResonanceImagingandComputed
Tomography
Cardiacmagneticresonanceimaging(MRI)hasemergedasausefulcompanion
toechocardiographyinthediagnosisofpediatriccardiactumors.Thisislargely
dueinparttotheabilityofMRItodifferentiatebetweentumortypesbasedon
theirappearanceondifferentimagingsequences.54–64
AtypicalMRIexaminationbeginswithsteadystatefreeprecession(bright
blood)cineangiographicsequencesinmultiplecardiacplanes.Thesesequences
provideexcellentvisualizationoftheheart,pericardium,vasculature,and
adjacentstructures.Tumorsize,location,andattachmentsaregenerallywell
visualizedandcanbeassessedthroughoutthecardiaccycletoassessfor
obstruction.Ventricularfunctionisalsowellvisualized.Spinecho(blackblood)
sequencesallowfortissuecharacterizationbasedonT1(fatenhancing)andT2
(waterenhancing)weightingandtheapplicationoffatsuppression.After
gadolinium-basedcontrastadministration,firstpassperfusionsequencesallow
forassessmentoftumorvascularity.Lategadoliniumenhancementsequences
canassessforfibrosisandareusefulforidentificationofthrombus.Magnetic
resonanceangiographycandemonstratetherelationshipofthetumortoblood
vessels,ifapplicable.Three-dimensionalacquisitionscanbeperformedwithor
withoutcontrastandallowformultiplanarreconstructionsandthree-dimensional
modelingandprinting.65MRIisunabletoassessforcalcification,whichisbest
seenbyx-ray–basedtechniquesandechocardiography.
Thesignalintensityofthetumoroneachsequenceisassessedandcompared
withpublishedtablesfordifferenttumortypes.54Certaintumorshave
pathognomonicfeaturessuchasstronglategadoliniumenhancementfor
fibromas,fatsuppressionforlipomas,andstrongfirst-passperfusionfor
vasculartumors(Fig.52.8).Featuressuggestiveofmalignancyareill-defined
boundaries,crossingoftissueplaneswithintheheart,involvementofboth
cardiacandextracardiacstructures,andlineargrowththroughlargeblood
vessels(Fig.52.9).
FIG.52.8 MRItumorcharacterization.(A–B)Vasculartumor(asterisk)of
theleftventricle.First-passperfusionsequenceshowsavidcontrastuptake
inthetumor.(C–D)Myocardialfattyfoci(arrows)intheepicardiumand
ventricularseptumofapatientwithtuberoussclerosiscomplex.(C)Strong
enhancementonT1-weightedsequenceand(D)nullingonfatsaturation
sequencesconfirmthefattynatureofthetumor.
