Andersons pediatric cardiology 1812

thereisabsenceoftheleftatrioventricularconnectionandtherightatriumis
connectedtoadominantleftventricle.Whenthereisatresiaoftheleft
atrioventricularvalveorabsenceoftheleftatrioventricularconnectionwiththe
rightatriumconnectedtoadominantrightventricleandtheventricularseptumis
intact,suchheartswillformpartofthehypoplasticleftheartsyndrome(see
earlier).Theaortaisusuallyatreticorelsecriticallystenotic.Inthesettingof
deficientventricularseptation,thearrangementisdescribedintermsofmitral
atresiawithpatentaorticroot,oftenwithadoubleoutletfromtherightventricle.
Irrespectiveoftheanatomiccombinations,thesurgicaloptionislikelytobe
conversiontotheFontancirculation.Thedescribedheterogeneitypointstothe
need,ineachcase,forfullsequentialsegmentalanalysis.

FIG.69.14 Anatomicsubstratesforatrioventricularvalvaratresia.Left,
Imperforatetricuspidvalveinthesettingofconcordantatrioventricular
connections.Right,Absenceoftherightatrioventricular(RAV)connection
inaheartwithclassictricuspidatresia.Botharrangementsarefunctionally
univentricular,buttheheartatlefthasbiventricularatrioventricular
connections.


FIG.69.15 Anatomicsubstratesformitralatresiainthesettingoftheright
atriumconnectedtothemorphologicallyrightventricle.(A)Concordant
connections,andtheatresiaisproducedbyanimperforatemitralvalve.(B)
Completeabsenceoftheleftatrioventricular(LAV)connectioninthesetting
ofthehypoplasticleftheartsyndrome.Theincompleteleftventricleisslitlike.

FIG.69.16 Typicalfeaturesofthemostcommonvariantoftricuspid
atresia.Left,Morphologyoftherightatrium.AsshowninFig.69.4,the
dimpleoverliestheatrioventricularcomponentofthemembranousseptum.

Right,Rightventricle,whichisincompletebecauseittotallylacksitsinlet
component.Theheartshownhasconcordantventriculoarterial
connections,withalonginfundibulumleadingtothepulmonarytrunk.The
infundibulumismuchshorterwhentheventriculoarterialconnectionsare
discordant.VSD,Ventricularseptaldefect.