Andersons pediatric cardiology 956
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angiogramisadequatetoidentifyandmeasurethecentralpulmonaryarteries
andMAPCAs.49Inourexperience,itisusuallyadequatetodetermine
interconnectionsbetweenMAPCAsandpulmonaryarteries,whichisan
importantconsiderationinourmanagementalgorithm,asdiscussedlater.
Computedtomographycanalsobehelpfulinolderpatientsforcharacterizing
pulmonaryarterialanatomy.Magneticresonanceimagingisusedoccasionally
fortheanatomicdefinitionofMAPCAsbutisinferiortocomputedtomography
orangiographyforthispurpose.Althoughnotwidelyperformed,measurement
ofindividualMAPCAandtotalpulmonarybloodflowswithcardiacmagnetic
resonancehasbeenreportedtohaveprognosticvalueforpredicting
postoperativerightventricularpressure(Video36.1).50
FIG.36.11 Thisseriesofpreoperativecomputedtomographyimagesina
patientwithtetralogyofFallot/pulmonaryatresia/majoraortopulmonary
collateralarteries(MAPCAs)includesmultiplanarreformattedimages
detailingtheorigins,courses,andconnectionsofMAPCAsandpulmonary
arteries.Theupperleftimageisaschematicdepictionofthepulmonary
bloodsupplyinthispatient.LPA,Leftpulmonaryartery;RLL,rightlower
lobe;RPA,rightpulmonaryartery;RUL,rightupperlobe.(Courtesy
FrandicsChan,MD,LucilePackardChildren'sHospitalStanford.)
CardiacCatheterizationandAngiography
Cardiaccatheterizationwithdirectradiocontrastangiographyremainsthegold
standardforthedelineationandcharacterizationofthepulmonarycirculation.
Dependingontheclinicalcircumstancesandfindingsonthecomputed
tomographyangiogram,itmaybereasonabletodeferangiographyuntilthe
patientisseveralmonthsofage,althoughitisoftenindicatedtoobtainthis
informationearlier.Theprimarygoalofcatheterizationandangiographyisto
characterizefullythepulmonarycirculation,theelementsofwhichare
summarizedinBox36.1.Someoftheanatomicvariationsandtechniquesare
depictedinFigs.36.12through36.15andVideos36.2through36.4.Inour
recentlyreportedinstitutionalexperiencewith485patients,37%hadundergone
sometypeofsurgerypriortoreferraltoourinstitution.45Insuchpatients,the
anatomyisacombinationofnativeandpostinterventionvasculature,butthe
samegeneralprinciplesasoutlinedearlierareappliedtotheevaluation.
Differenttechnicalapproachesandtoolscanbeusedtoperformthisassessment,
includingtransvenous(prograde)ortransarterial(retrograde)aortography(see
Video36.2),selectiveangiographicinjectionatdifferentlevelsofthe
vasculaturewithvariouspreshapedormodifiedend-holecatheters(seeFigs.
36.12to36.14),balloon-occlusionangiograms(seeFig.36.15andVideo36.3),
useof0.014-infloppywiresandmicrocatheterstotraversesmallortortuous
arteries(seeVideo36.4),andmore.Thespecifictechniquesuseddonotmatter
inthemselvesaslongasallofthenecessaryinformationisobtained.
Box36.1
ObjectivesofPreoperativeCardiac
CatheterizationinPatientsWith
TOF/PA/MAPCAs
