Among the 194 children studied, 30 (15%) had abnormal findings on echocardiogram that explained the murmur. The cardiac diseases diagnosed were atrial septal defects (ASDs) in 9 children, ventricular septal defects (VSDs) in 5, ASD associated with VSD in 1, sonographically important mitral regurgitation in 7, tricuspid regurgitation in 1, aortic valve stenosis in 3, pulmonary valve stenosis in 1, coarctation of the aorta in 1, patent ductus arteriosus in 1, and coronary-to–pulmonary artery fistula in 1. The clinical and echocardiographic characteristics of the children are shown in Table 1.
Persistence of the murmur on standing, the absence of a decrease of its intensity, location on the left upper sternal border or at the apex, and presence of radiation were significantly associated with a pathologic murmur (Table 2).
Overall, 100 children had complete disappearance of their murmur when they stood up. Within this group, only 2 (2%) had an abnormal echocardiogram. One, a girl aged 13 years, had an ASD, and needed percutaneous closure of the defect. Her murmur was located on the left upper sternal border without radiation. The other, a boy aged 12 years, had a trivial muscular VSD, and required neither intervention nor specialized follow-up. His murmur was located at the low to middle left sternal border without radiation.