Perimembranous ventricular septal defects (also called membranous VSD'S) are located in the membranous septum, a relatively small portion of the septum ...JumptocontentALERT:VaccineWalk-InClinicThisWeekforPatientswithaMichiganMedicineMedicalRecordNumber(MRN).Learnmore.OtherUMHSSitesYouarehereHome›Conditions&Treatments›CongenitalHeartOverview›ConditionsWeTreat›VentricularSeptalDefect(VSD)VentricularSeptalDefect(VSD)Visitour COVID-19GuidelinesforAt-RiskPatientspage toviewcoronavirusinformationdevelopedforyouandour KeepingOurPatientsSafepage tolearnwhatwearedoingtogiveyouasafe,reliableplacetoreceivecare.Whatisaventricularseptaldefect?Ventricularseptaldefectisthemostcommoncongenitalheartdefectandaccountsfor20-30%ofchildrenseeninlargepediatriccardiologyclinics.Theexactincidenceisnotknownwithestimatesrangingfrom2to5outofevery1000babiesborn.Thecauseoftheproblemisnotwellunderstood.Aventricularseptaldefect(VSD)isadefectorhole(1)inthewallthatseparatesthelowertwochambersoftheheart.Thesechambersarecalledtheventricles(2)andthewallseparatingthemiscalledtheventricularseptum.Achildcanhavesingleormultipleventricularseptaldefects.VentricularseptaldefectsalsooccurinassociationwithmorecomplexheartdefectssuchasTetralogyofFallotandtranspositionofthegreatvessels.Theinformationonthispageappliestopatientswithaventricularseptaldefectandanotherwisenormalheart.Ventricularseptaldefectscanbefurtherdescribedby1)sizeofthedefect,2)locationofthedefect,3)whetherthereismorethanonedefectpresent,and4)thepresenceorabsenceofaventricularseptalaneurysm.Thesizeofthedefectisusuallydescribedassmall,moderate,orlarge.Ingeneral,smalldefectscausenosymptomsduringinfancyorchildhoodandoftenclosespontaneously.Moderateandlargedefectsarelesslikelytoclosespontaneously,mayresultincongestiveheartfailure,andmoreoftenrequiresurgicalclosure.Sometimes,thetermrestrictiveornon-restrictiveareusedtodescribethesizeofthedefect.Thetermrestrictivedescribessmalldefectsthatallowlittleornobloodtoflowfromtheleftsideofthehearttotherightsid