Echocardiographic evidence of left ventricular bands in infants and children.

M-mode and two-dimensional echocardiographic studies were carried out on 100 consecutive neonates, infants and children to evaluate the incidence of left ventricular chordae or bands. These fibromuscular structures were noted in 61 subjects and were seen to traverse both the long and short axes of the left ventricle. Although a single left ventricular band was usually noted, several subjects had multiple bands. These bands were seen in normal subjects and in patients with a wide variety of congenital cardiac lesions. Distortion of left ventricular geometry was noted in one subject. Identification of these linear echoes is essential to allow differentiation of left ventricular bands from true anatomic left ventricular outflow tract obstruction or septal thickening.