Fontan procedure. This surgery is usually done when your child is between 18 months and 4 years of age. The surgeon creates a path for the ...Scheduleyourappointmentnowforsafein-personcare.Learnmore:MayoClinicfactsaboutcoronavirusdisease2019(COVID-19)Our COVID-19patient andvisitorguidelines,plustrustedhealthinformationLateston COVID-19vaccination bysite:ArizonapatientvaccinationupdatesArizona,FloridapatientvaccinationupdatesFlorida,RochesterpatientvaccinationupdatesRochesterandMayoClinicHealthSystempatientvaccinationupdatesMCHSSkiptositenavigationSkiptoContentThiscontentdoesnothaveanEnglishversion.ThiscontentdoesnothaveanArabicversion.SectionsforHypoplasticleftheartsyndromeSymptoms&causesDiagnosis&treatmentDoctors&departmentsCareatMayoClinicPrintDiagnosisBeforebirthIt'spossibleforababytobediagnosedwithhypoplasticleftheartsyndromewhilestillinthewomb.Yourdoctormightbeabletoidentifytheconditiononaroutineultrasoundexamduringthesecondtrimesterofpregnancy.AfterbirthAfteryourbabyisborn,adoctormightsuspectaheartdefect,suchashypoplasticleftheartsyndrome,ifyourbabyhasgrayish-blueskincolororhastroublebreathing.Yourbaby'sdoctormightalsosuspectaheartdefectifheorshehearsaheartmurmur—anabnormalsoundcausedbyturbulentbloodflow—whenlisteningtotheheartwithastethoscope.Doctorsusuallyuseanechocardiogramtodiagnosehypoplasticleftheartsyndrome.Thistestusessoundwavesthatbounceoffyourbaby'shearttoproducemovingimagesthatcanbeviewedonavideoscreen.Ifyourbabyhashypoplasticleftheartsyndrome,theechocardiogramwillshowasmallerthannormalleftventricleandaorta.Theechocardiogrammightalsoshowabnormalheartvalves.Becausethistestcantrackbloodflow,italsoshowsbloodmovingfromtherightventricleintotheaorta.Inaddition,anechocardiogramcanidentifyassociatedheartdefects,suchasanatrialseptaldefect.CareatMayoClinicOurcaringteamofMayoClinicexpertscanhelpyouwithyourhypoplasticleftheartsyndrome-relatedhealthconcernsStartHereMoreInformationHypoplasticleftheartsyndromecareatMayoClinicEchocardiogramFetalultrasoundTreatmentH