Ventricular septal defect (VSD):A holeintheseptum(the wall) between the lower chambers of the heart (theventricles).
VentricularSeptalDefect is the most common type of heartmalformation(congenitalheart disease). At least 1 baby in every 500 is born with aVSD.
A VSD letsbloodfrom theleft ventricle(where it is under relatively high pressure)分流器into theright ventriclewhich has to do extra work to handle the additional blood, may have trouble keeping up with the load, enlarge, and fail. Thelungsreceive too much blood under too great pressure, the arterioles (small arteries) in the lungs thicken up in response, and permanentvasculardamage can be done to the lungs.
Small VSDs (less than 0.5 squarecmin area) permit only minimal shunting of blood and the pressure in theright ventricleremains normal and the heart (and lungs) function normally. Surgical repair is not recommended for small VSDs.
No matter what size a VSD is, it carries an increased risk forinfectionof the heart walls and valves (endocarditis). To prevent endocarditis, anyone with a VSD should take antibiotics before dental and other particular procedures.
With a large VSD (usually one greater than 1.0 square cm in area), there is a significant shunt into the rightventricle, excessive blood flow into the lungs, and pulmonary hypertension. The child may have labored breathing, difficulty feeding, and grow poorly. Medically, the heart that has a large VSD should be kept strong. Vascular disease in the lungs must not be allowed to develop.Surgeryshould be done to close a large VSD.
Theprognosis(outlook) with VSD is generally excellent.
