The ACC/AHA guidelines for the management of adult precordial disease classify the size of ventricular septal defects as follows: 1. Small ventricular septal defects have a diameter less than or equal to 25% of the aortic valve diameter, small ventricular defects with small left-to-right shunts, no left ventricular volume overload, no pulmonary hypertension, and a systolic murmur. 2. A medium-sized ventricular septal defect with a diameter greater than 25% of the aortic valve diameter and less than 75% of the aortic valve diameter, with a small-moderate left-to-right shunt, mild-moderate left ventricular volume overload, and no or mild pulmonary hypertension. Patients may be asymptomatic or may have mild heart failure symptoms. Medication, spontaneous absolute ventricular defect reduction or relative ventricular defect reduction due to physical growth may relieve symptoms. Large ventricular septal defects with a diameter greater than or equal to 75% of the aortic valve diameter usually have a large left-to-right shunt, moderate-to-severe left ventricular volume overload, and moderate-to-severe pulmonary hypertension. Most patients with large ventricular ischemia have had clinical manifestations of congestive heart failure in infancy. Very few patients with large ventricular defects lack even a postnatal drop in pulmonary artery pressure, do not develop massive left-to-right shunts, and present early (in childhood, adolescence, or early adulthood) with right-to-left shunts and Eisenmenger syndrome.