Andersons pediatric cardiology 813
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timeforoptimumforvalvarrepairissomewherebetween3and6months.58
Stephensandcoworkersfoundthatgoodresultscanbeachievedwithan
individualapproacheveninchildrenyoungerthan3monthsofage.59Severely
symptomaticpatientsmaybenefitfromearlieroperativerepairbecauseoffailure
tothrive.Inthesepatients,theatrioventricularannulusmaydilateastheresultof
ventriculardilatation.TheAchillesheelisthetextureoftheatrioventricular
valvartissue,whichisfriableafterbirthandmaycausesuturestotearthrough.
Valvartissuemayfibroseatthesiteofregurgitation,whichfacilitatessuturing.
Butifrepairispostponedtoolongitmaybecomemoredifficult.
ObjectivesofSurgicalCorrection
Surgicalcorrectionaimsatclosureofallseptaldefectstoabolishshunting.The
zoneofappositionbetweensuperiorandinferiorbridgingleafletsmustbeclosed
atalltimes,unlessspecificallycontraindicated.Thepolicynottoclosethezone
whenthevalveiscompetenthasresultedinlargenumbersofreoperationsfor
valvarregurgitation.Themostfrequentcontraindicationtoclosingthezoneof
appositionisabsenceorhypoplasiaoftheleftmuralleaflet,whereclosureofthe
zonewouldrenderthevalvestenotic.Whenstrivingtoachievetheseprimary
goals,careshouldbetakentoavoidtwocomplications,namelydamagetothe
atrioventricularconductionsystemandobstructionwithintheleftventricular
outflowtract.
ClosureoftheSeptalDefect
Themannerinwhichthedefectisclosedcanhaveaprofoundeffectonthe
subsequentarchitectureoftheatrioventricularvalvarcomplexbecausedefect
andvalveareinseparablepartsofthethree-dimensionalanomalyofthe
abnormalcommonatrioventricularjunction.Theshapeofthepatchorpatches,
andthetechniqueusedforinsertionofsutures,therefore,areofutmost
importancenotonlyforseptalclosurebutparticularlyforpostoperativevalvar
function(Fig.31.40).
FIG.31.40 Howboththeanteroposteriorandsuperoinferiordimensionsof
theventricularpatchareessentialtothecoaptationofthebridgingleaflets.
Ifthepatchistoowideand/ortoodeep,coaptationwillnotbeideal.
Methodsofrepaircanbecategorizedclassicallyasuseofoneortwopatches
forclosureoftheentiredefectpresumingthatthereareatrialandventricular
componentstoclose.Afurthercategorizationiswhetherornotbridgingvalvar
leafletsarecutinordertoexposetheatrioventricularvalvarannulusatthe
ventricularseptaljunction.Thecuttingofbridgingleafletscanbeappliedtoone
orboththesuperiorandinferiorbridgingleafletsdependingontheirextentof
bridging.Afurthervariableisthepossibilityofattachingoneorbothbridging
leafletsdirectlytotheseptalcrest.Permutationofthesestrategiesresultsinat
leasteightpossiblecombinationsoftechniques,whicharelistedbelow:
■Onepatch,andcuttingbothbridgingleaflets(Fig.
31.41).60,61
FIG.31.41 Classicsingle-patchtechniqueforsurgicalrepair,in
whichbothbridgingleafletsarecutintheplaneoftheventricular
septumtoexposeitscrest.Thesinglepatchissuturedtotheright
sideoftheventricularseptum;thereafterthecutedgesofthe
bridgingleafletsaresuturedtogether,sandwichingthepatch
betweenthem.
■Onepatch,butleavingthebridgingleafletsintact.
Thisisonlypossiblewithminimalbridgingofboth
bridgingleafletsandconstitutesanumericallyminor
subset(Fig.31.42).
