Andersons pediatric cardiology 1181
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CatheterIntervention
Atmanycenters,transcatheterballoonaorticvalvuloplastyisconsideredfirstlinetreatmentforcriticalaorticvalvestenosis.80,81Ballooningrelievesaortic
stenosisbycausingarupturealongthelinesofleastresistance,eitheralongthe
underdevelopedcommissuresorintothecusptissue.
Earlymortalityincriticalaorticstenosisafterballoonvalvuloplastyis
between9%and14%.73,82,83Comparedwithsurgicalaorticvalvotomyfor
criticalaorticstenosis,balloonvalvuloplastywasassociatedwithgreater
reductioninthedegreeofstenosisbutresultedinhigherriskforaortic
regurgitation.80Theincidenceofmoderateorsevereaorticregurgitationshortly
afterballoonvalvuloplastyisreportedtobebetween7%and33%.82,84,85
However,thesurvivalandfreedomfromreinterventionat5yearsweresimilar
betweenthesurgicalandtranscatheteraorticvalveinterventiongroups.Adverse
eventsafterballooninterventionincludea15%incidenceofaorticwallinjury,a
2.6%incidenceofproceduralfemoralarterydamage,anda5%incidenceof
injuriestotheheartitself,suchasruptureofthevalvesormyocardial
perforation.82,85,86
SurgicalIntervention
Newsurgicaltechniqueshaveincreasedtheenthusiasmforopensurgical
valvotomyastheprimaryinterventioninpatientswithcriticalaorticstenosis.
Opensurgicalvalvotomyallowsconstructionofacuspanatomythatisasclose
aspossibletothenormalanatomy,potentiallyallowingforamoredurableaortic
valverepair.Shavingofthickenedcusps,excisionofobstructivemyxomatous
nodularities,andmobilizationofthecuspseffectivelyincreasetheorificeareaof
thevalveinanytypeofmorphology,withaminimalriskofcreating
regurgitation.Ifcommissuralpostsaredeveloped,tricuspidalizationofthevalve
isusuallypossible,thuspreservingthenativeaorticvalveinthemajorityof
patientsinthelongrun.Surgicalinterventionalsohastheadvantageof
addressingassociatedcardiaclesionsatthesametime(Video44.6).
Earlymortalityafteropenvalvotomyisreportedtobebetween6%and
19%.70,87–93Overallsurvivalisbetween70%and90%at1yearandusually
remainsunchangedat5yearsand10yearsoffollow-up.The10-yearevent-free
survivalforcriticalneonatesisbetween50%and70%.70,90–92Thesefigures
comparefavorablywiththe29%to54%event-freesurvivalat10yearsreported
afterballoonvalvotomy.82,90,91,94,95
HybridApproach
Ahybridprocedurethatincorporatesbothcatheterandsurgicalmodalitiesserves
asabridgetoamoredefinitiverepairforpatientswithaborderlineleftventricle
and/ordepressedleftventricularfunction.70,96–98Ahybridapproachmayinvolve
somecombinationofbilateralpulmonarybanding,enlargementoftheatrial
septalcommunicationtodecompresstheleftheart,maintainpatencyofthe
arterialduct,andeitheraballoonorsurgicalaorticvalvotomy(Video44.7).This
conceptmaysignificantlyreducetheriskofadefinitiveprocedurebyproviding
patientsmoretimetorecover,mature,and“declarethemselves”aseitherone-or
two-ventriclecandidates.98
Long-TermOutcomes
Bothballoonvalvotomyandopenvalvotomyarefirmlyestablishedaseffective
initialtreatments,withencouragingsurvivalbenefits.70,73,82,83,85,88–92,99
Mortalityisassociatedwithhypoplasiaoftheleftheartstructuresandthe
presenceofendocardialfibroelastosis.100However,bothmethodsarepalliative
proceduresandreinterventionislikely.Althoughpatientsundergoingopen
valvotomyaremorelikelytohaveresidualstenosis,thoseundergoingballoon
valvotomyaremorelikelytodevelopprogressiveinsufficiency.75Tricuspid
valvemorphologyshowedsuperiorlong-termoutcomesofopenvalvotomyin
comparisonwithballoonvalvotomyregardingpreservationofthenativeaortic
valve.70,93
ManagementofNoncriticalAorticStenosis
MedicalManagement
Intheolderchildoradolescentwithasymptomaticvalvaraorticstenosis,there
arenomedicaltherapiesthatareproventopreventordelaytheprogressionof
stenosisorneedforintervention.Treatmentofhypertension,ifpresent,is
reasonabletoreducetheoverallafterloadontheleftventricle;however,
medicationsforafterloadreductionarenotindicatedinnormotensivepatients.
Thereistheoreticalconcernthatafterloadreductionmayprecipitateadecrease
incardiacoutputinthesettingofhemodynamicallysignificantaorticstenosis.
Antihypertensives,ifindicated,shouldbestartedatalowdoseandgradually
titratedupasneededuntilpatientsarenormotensive.
Lipid-loweringtherapywithstatinmedicationshasbeenstudiedinadultswith
valvaraorticstenosiswithagoalofreducingcuspcalcificationand
hemodynamicprogression.However,severalprospectiverandomizedcontrolled
trialshavenotdemonstratedbenefitwithstatinswithregardstodisease
progression,andthereforetheyarenotrecommendedforroutinemanagementin
patientswithvalvaraorticstenosis.101,102
Duetoriskforsuddendeathwithexercise,activityrestrictionsshouldbe
consideredinpatientswithsevereaorticstenosis.Themostrecentstatement
fromtheAmericanHeartAssociationandAmericanCollegeofCardiology
recommendsthatpatientswithsevereaorticstenosisberestrictedfrom
competitiveathleticsandparticipateonlyinlow-intensityactivities.103Those
withmildormoderateaorticstenosiscanparticipateinallcompetitivesportsas
longastheyhavenosymptomswithexercise,lessthanorequaltomildleft
ventricularhypertrophy,absenceofleftventricularstrainpatternon
electrocardiogram,andnormalmaximumexercisestresstestwithoutevidenceof
ischemia,arrhythmias,ordropinbloodpressure.103
Althoughpatientswithbicuspidaorticvalveareatriskforendocarditis,
antibioticprophylaxisisnotrecommendedpriortodentalworkorother
procedures.58,104However,patientsshouldbecounseledontheimportanceof
goodoralandskinhygienetoreducetheriskofbacteremiafromdailyactivities.
TimingofIntervention
Forasymptomaticchildrenandyoungadultswithsevereaorticvalvestenosis,
theindicationsandtimingforaorticvalveinterventionarenotwelldefined(Box
44.2).Surgicaltimingisbasedonweighingtherelativerisksofnointervention
(i.e.,riskofcongestiveheartfailureandsuddendeath)versustherisks
associatedwiththeprocedure(catheterorsurgical).
Box44.2
IndicationsforInterventionforSevereValvar
