Congenitally bicuspid aortic valves. Clinicogenetic study of 41 families.

The families of 41 patients with surgically proved isolated bicuspid aortic valves were examined. There were 275 first degree relatives of whom 220 were living, and 188 (85.5%) of these were examined. Seven first degree relatives were found to have aortic valve disease, and in a further 11 there was 'doubtful' evidence of bicuspid aortic valves. In 6 families there was more than 1 affected member and in an additional 7 families there was 1 or more 'doubtful' first degree relative. The minimum family incidence was therefore 14.6 per cent, or 31.7 per cent if 'doubtful' cases were included. The inheritance is most probably multifactorial, but occasionally the condition may occur as an autosomal dominant. The difficulties of diagnosing bicuspid aortic valves before the development of obstruction of left ventricular outflow were encountered and are discussed. The association of a bicuspid aortic valve with asymmetric septal hypertrophy, hypertrophic cardiomyopathy, and Marfan's syndrome was also noted.

Familial study of hypertrophic cardiomyopathy and congenital aortic valve disease.

A woman with coexisting calcific aortic valve disease and hypertrophic obstructive cardiomyopathy was studied before homograft replacement of the aortic valve and in the second and fourth postoperative years. Postoperative hemodynamic findngs, in studies performed with and without pharmacologic agents, were similar to those of patients with hypertrophic cardiomyopathy. Echocardiographic studies 9 years after operation revealed asymmetric septal hypertrophy and systolic anterior motion of the mitral valve leaflet echoes. The patient eventually died from carcinoma of the bronchus 9 years after aortic valve replacement. At autopsy the heart showed the features of hypertrophic obstructive cardiomyopathy. In addition, the aorta the arrangement of the smooth muscle and elastic fibers was disordered. Subsequently, 10 asymptomatic relatives from four generations of this family were studied clinically and with echocardiography. Unsuspected asymmetric septal hypertrophy was found in four, and the pattern of the aortic valve echoes was compatible with a bicuspid valve in three. Three relatives had coexisting asymmetric septal hypertrophy and a bicuspid aortic valve. This family study shows that hypertrophic cardiomyopathy and bicuspid aortic valve may coexist and may be inherited as a dominant characteristic with variable manifestations.

Echocardiographic spectrum of hypertrophic cardiomyopathy.

Echocardiographic patterns in 15 patients with hypertrophic cardiomyopathy were compared with those in 30 healthy persons. Correlations with angiocardiographic data indicated that most of the anatomical abnormalities in hypertrophic cardiomyopathy can be assessed reliably by echocardiography. These include abnormal mitral valve motion, a reduction of the anteroposterior dimension of the left ventricular outflow tract and of the left and right ventricular cavities, increased thickness of the interventricular septum and the posterior left ventricular wall. Comparision of the haemodynamic and echocardiographic data showed that some degree of abnormal mitral valve motion during systole may occur in the absence of left ventricular outflow tract obstruction. On the other hand, it need not always be present with left ventricular outflow tract obstruction. Other, hitherto unrecognized, abnormalities in hypertrophic cardiomyopathy detected by this technique were: (1) Aortic valve regurgitation in three out of nine patients with evidence of left ventricular cutflow tract obstruction at cardiac catheterization. (2) Left ventricular inflow tract obstruction at the mitral valve level associated with gross septal hypertrophy (five cases). (3) Abnormal forward displacement of the posterior mitral valve leaflet and of the chordae tendineae during systole in 10 patients, in seven of whom there was confirmatory angiocardiographic evidence. Seven patients with miscellaneous cardiac disorders are described in whom asymmetric septal hypertrophy was revealed by echocardiography. In one of these patients coexisting hypertrophic cardiomyopathy was excluded histologically; thus asymmetrical septal hypertrophy is not confined to patients with hypertrophic cardiomyopathy.