Andersons pediatric cardiology 803
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PresentationandSymptomatology
Inthecurrenteraofroutinescreeningofpatientsdeemedathighrisk,suchas
thosewithDownsyndrome,andtheincreasinglikelihoodofprenataldiagnosis,
thefullclinicalpictureasdescribedinthissectionisencounteredinaneverdecreasingnumberofpatients.Patientswithlargeventricularcomponentstothe
septaldefect,severeleftatrioventricularvalvarregurgitation,significantleft
ventricularhypoplasia,orcomplicatingassociatedlesionssuchasaortic
coarctationpresentwithseverecardiacfailureinearlyinfancy.Iftheventricular
componentwastheonlyproblem,therewouldbealatentperiodof1to2
monthsoccurringafterbirthbutpriortopresentation.Infantswithboth
ventricularandatrialcomponentstendtopresentearlierowingtothemorerapid
increaseinleft-to-rightshunting.Inanumberofinfants,however,pulmonary
vascularresistanceremainshighafterbirth,andtheymaypresentlateduetoa
lackofsymptomsininfancy.ThisisanobviousriskinthesettingofDown
syndrome.Asaresultofroutinescreeningprogramsforcardiacdiseaseinthese
children,developmentofEisenmengersyndromeistodayrare.Patientswithout
thesecomplicatingfactors,typicallythosewithseparateatrioventricularvalvar
orificesandthepotentialforshuntingexclusivelyatatriallevel,oftenescape
detectionoftheircardiacdiseaseininfancy.Theypresentduringchildhoodwith
anincidentalmurmuror,inthosewithacommonatrium,mildcyanosis.Inrare
instancestheymaynotpresentuntiladolescenceoradultlife.
ClinicalFindings
Inthosepatientswithseparateatrioventricularvalvarorificesandshunting
confinedexclusivelyattheatriallevel,theclinicalfindingsareasexpectedfor
simpleinteratrialcommunicationswithintheovalfossa(seeChapter29).
Consequentlyinfantsandchildrenareusuallyfreefromsymptoms,although
somemayhaverecurrentchestinfections.Onauscultation,widesplittingofthe
secondheartsoundisthemostcharacteristicfeature,althoughininfantsand
youngerchildrenthesplitmaynotbefixed.Anejectionsystolicmurmurtypical
ofincreasedflowacrossanormalpulmonaryvalve,grade2or3inintensity,is
typicallyheard,beingmaximalattheupperleftsternaledge.Whenthereisa
largeleft-to-rightshunt,theremayadditionallybeamidsystolicrumbleaudible
alongthelowerleftsternaledgerelatedtoincreasedflowacrossanormal-sized
rightatrioventricularvalve.
Inthepresenceofacommonatrioventricularvalvarorificeorsignificant
ventricularshunting,failuretothriveandsignsofcongestiveheartfailureare
frequentduringearlyinfancy.Thesepatientsusuallypresentwithinthefirst3
monthsoflife.Recurrentchestinfectionsarealsoencountered.Thetypical
findingsonclinicalexaminationareanundernourishedinfantwithtachycardia,
tachypnea,andhepatomegaly.Theprecordiumishyperactive,andasystolic
thrillissometimespalpatedatthelowerleftsternalborder.Thefirstheartsound
isaccentuated,withthesecondsoundbeingnarrowlysplit,itspulmonary
componenthavingincreasedintensity.Murmursheardcanvarymarkedlyin
theircharacteristics,fromashortandsoftmurmur,asoftejectionsystolic
murmuratthemid-to-lowerleftsternalborderinthosewithalargeventricular
septaldefectandelevatedpulmonaryvascularresistance,toaloudpansystolic
murmurduetoventricularshuntingandheardatthesamesite.Notinfrequently,
asoftmiddiastolicmurmurisheardattheleftlowersternaledgeortheapex,
reflectingincreasedflowacrossthecommonatrioventricularvalve.
Thesecardinalphysicalfindingsreflectingdifferencesinthespecificanatomy
maybemodifiedbythepresenceofatrioventricularvalvarregurgitation.This
canproducesymptomsofalargeleft-to-rightshuntandcongestiveheartfailure,
eveninaninfantwithshuntingexclusivelyattheatriallevel.Significantvalvar
regurgitationwillbeassociatedwithapansystolicmurmurheardmaximally
betweenthelowerleftsternaledgeandtheapex.Inthissetting,theremayalso
beaprominentmid-diastolicapicalmurmurduetoincreasedflowacrossthe
atrioventricularvalve.Thepresenceofassociatedmalformationscanfurther
modifythesefindings.Cyanosis,forexample,couldreflectabnormalsystemic
venousdrainage,commonmixingatatriallevel,orcoexistingtetralogyofFallot.
Asindicatedintheprevioussection,infancyisoccasionallyuneventful,
particularlyinthosepatientswithDownsyndrome.Thepatientcanpresentlater
inchildhoodwithEisenmengersyndrome.Suchpatientsarecyanotic,andthe
systolicanddiastolicmurmursnotedearlierareusuallyreducedorabsent.Such
anabsenceofmurmursislesslikelythaninthosewithisolatedventricularseptal
defects,forexample,becauseofthefrequencyofatrioventricularvalvar
regurgitation.Pulmonaryvalvarclosureisevenmoreaccentuated,andthe
secondheartsoundmaybecomesingle.Anearlydiastolicmurmurofpulmonary
regurgitationmaysupervene.
Inpatientswithverylittleshunting,clinicalsymptomsarelimitedto
atrioventricularvalvarregurgitation,whichcanbecomeclinicallymanifestin
adultlife.Thesamegoesinallprobabilityfortheveryrarepatientshavinga
commonatrioventricularjunctionbutwithintactseptalstructures.
