D is a 16 yr old high school student who is in the sportsclinic prior to beginning of baseball practice,has no medicalhistory.Assesment reveals he gets 'winded' earlier than most boyson the team.He attributes this to needing to get in bettershape.The physical exam is unremarkable except for a grade IIIsystolic murmur heard over the entireprecordium.An echocardiogram and cardiac cath reveals aventricular septal defect (VSD) with moderate pulmonaryhypertension.
Q1 A VSD is usually an acyanotic defect. Why is this ?
Q2 What is the mechanism and significance of pulmonaryhypertension?
Q3 What other disorders besides VSD can produce a systolicmurmur?How can character of the murmur and pattern of radiation beused to differentiate among these etiologic factors?
Q4 Is it necessary to close a VSD?What are the commoncomplications of untreated VSD?