Andersons pediatric cardiology 1784
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age.48Ischemictime(traveldistance,complexityofsurgery)anddonorage
shouldbetakenintoconsiderationforolderpediatriccandidatesindeciding
aboutacceptingapotentialdonorheart.Coldstaticstoragehasbeenthe
mainstayoforganpreservation;however,alternatestrategiesareonthehorizon,
includingcontinuoushypothermicornormothemicdonorperfusion49,50and
donationaftercardiacdeath.51
Althoughrarelyaconsiderationinadults,inchildrenthedonorheartmustbe
appropriatelymatchedinsizetotherecipient.Widelydisparateratiosofweight
betweendonorandrecipienthavebeenreported,withvariableeffectson
outcome.52–55MultivariableanalysisoftheISHLTdatabasehasshownaratioof
lessthan0.5ormorethan2.5tobeassociatedwithanincreasedriskfor
mortalitywithinthefirstyear.2However,donor-to-recipientweightratiowasnot
identifiedasariskfactorinamultivariableanalysisofthePHTSregistry.48
SurgicalTechniques
Thebasictechniquesforimplantationofacardiacallografthavenotchanged
significantlysincetheiroriginaldescription.56Inchildren,thesizeofthepatient,
thelocationoftheheart,atrialarrangement,systemicvenousanatomy,and
pulmonaryvenousanatomymustallbetakenintoconsiderationwhen
determiningthesurgicalapproach(Video67.1).Insomecomplexformsof
congenitalcardiacdiseasetheremaybeaneedtoharvestportionsofthe
pulmonaryarteries,aorta,inferiorvenacava,orthebrachiocephalicveinto
facilitatetheanastomoseswithintherecipient.Thesedetailsshouldbeplanned
duringassessmentpriortotransplantation.Thesurgicalchallengespertainingto
transplantationforpatientswithcomplexlymalformedheartshavebeen
summarizedintheliterature.57
Therearetwomaintypesofatrialanastomoses,bicavalandbiatrial.The
bicavalapproachhasbeenreportedtobeassociatedwithfewer
tachyarrhythmias,slightlybetterhemodynamics,lesstricuspidregurgitation,a
lowerincidenceofpacemakersupport,andbetterexercisetolerance.58,59The
biatrialtechnique(usuallyreservedforsmallerpatients)hasbeenassociatedwith
disturbancesofconductionrequiringtheplacementofpacemakersinuptoonesixth,ahigherriskofthromboembolism,pooratrialsynchrony,andmore
atrioventricularvalvarregurgitationduetodistortionoftheatrialanatomy.The
onlyrandomizedtrialdemonstratedthatthebicavaltechniqueresultedinbetter
hemodynamicsandsurvival.60
ManagementoftheRecipient
Thereareseveralimportantpostoperativeissuesthatmustbeanticipatedand
appropriatelymanagedintherecipient.Theacutelydenervatedheartis
frequentlyinslowsinusorjunctionalrhythm.Ventriculardysfunctionasaresult
ofischemia-reperfusioninjury,compoundedbybraindeathofthedonor,can
leadtoacutedecompensationofthetransplantedheart,rightventricularfailure
beingaspecificconcern.Thelatterisexacerbatedbyelevatedpulmonary
vascularresistance.Ingeneral,strategiesofpostoperativemanagementinclude
thefollowing:(1)maintainingcoronaryarterialperfusionandsystemicblood
pressurebyinotropicsupport;(2)pulmonaryvasodilatorstoreducetheright
ventricularafterloadandpulmonaryvascularresistance;(3)chronotropywith
eitherpacingorisoproterenol;(4)optimizationofpreloadtotheischemicand
dilatedrightventriclebylimitingthecirculatingvolumeandcentralvenous
pressure,especiallyifthereissystemichypotensionand/orlowcardiacoutput
unresponsivetofluidboluses;(5)ensuringanatrioventricularsynchronous
rhythm;(6)optimizingventilatormanagementtoavoidhypercapniaand
acidemiabyoptimizingpeakearlyexpiratorypressuresandearlyextubation;
and(7)providingearlymechanicalassistancetofacilitaterecoveryofthe
transplantedheartifclinicallywarranted.
SpecificPostoperativeComplications
Stenosiscandevelopatanyoftheanastomosissitesincludingthesystemic
venousanastomoses,thepulmonaryarterialanastomoses,ortheanastomosisof
thereconstructedaorta.Thesemaybeamenabletointerventionaltreatment,
usuallyrequiringimplantationofstents.Lesscommonly,thesizeoftheleftatrial
anastomosismaybeaproblem.Ifitishemodynamicallysignificantandnot
recognizedintheoperatingroomatthetimeofthepostoperative
transesophagealechocardiogram,itwilllikelycausehemodynamicinstabilityin
theimmediateperiodsubsequenttotransplantationandmayrequireearly
reoperation.
PosttransplantEducation
Thetransplantteamprovidessupportandeducationtothefamilyregarding
recoveryandpossibleposttransplantcomplications.Signsandsymptomsof
rejectionandinfectionmustbereviewedandthetransplantcoordinatormust
arrangefornecessarydischargeeducationwithtransplantteammembersfrom
thepharmacy,psychosocial,anddietarydepartments.Otherkeyteachingpoints
forthefamilyincludemedicationsandtheirsideeffects,healthyliving,when
andhowthefamilyshouldcontactthetransplantteam,physicalactivity,regular
dentalexams,cancerscreening,bonehealth,sexuality,pregnancyandbirth
control,andtravel.Thefamilyshouldbeeducatedregardingroutine
posttransplantcareaspereachcenter'sclinicalpractice.
