The Force Ballistocardiogram as an Index of Severity in Congenital Aortic Stenosis

ONE of the most frustrating and frequent problems faced by the pediatric cardiologist is that of differentiating between a child with mild and physiologically unimportant congenital aortic stenosis and one whose lesion is severe and therefore potentially dangerous. In an asymptomatic younger child with the typical murmur and thrill of aortic stenosis but no evidence of left ventricular hypertrophy on vectorcardiogram, electrocardiogram, or x-ray, the problem may not be acute as far as clinical management is concerned, since procrastination is probably indicated. The situation is drastically altered, however, when a 12-year-old seeks permission to engage in a competitive sport or to participate in a strenuous physical-education program, and a definite answer must be given. That aortic stenosis can be a treacherous and lethal lesion has been extensively documented, and it is now generally accepted that when the aortic systolic transvalvular pressure gradient is over 50 mm Hg at a normal cardiac output, or when the calculated aortic