Complications

A small ventricular septal defect may never cause any problems. Medium or large defects can cause a range of disabilities — from mild to life-threatening. Treatment can prevent many complications.

Complications can include:

• Heart failure. In a heart with a medium or large VSD, the heart works harder and the lungs have too much blood pumped to them. Without treatment, heart failure can develop.
• Pulmonary hypertension. Increased blood flow to the lungs due to the VSD causes high blood pressure in the lung arteries (pulmonary hypertension), which can permanently damage them. This complication can cause reversal of blood flow through the hole (Eisenmenger syndrome).
• Endocarditis. This heart infection is an uncommon complication.
• Other heart problems. These include abnormal heart rhythms and valve problems.