Noninvasive follow-up study in hypertrophic obstructive cardiomyopathy.

: The clinical course of hypertrophic cardiomyopathy with left ventricular outflow obstruction showed a symptomatic progression in 25% of patients, independent of the of degree of left ventricular obstruction. Echocardiographic and mechanocardiographic examinations showed a close relationship between severity of asymmetric ventricular hypertrophy and diastolic failure. During the follow-up septal hypertrophy became more severe without left ventricular dilatation. Global diastolic function deteriorated and the left atrium dilated. The probability of survival was 67.2%. Our data suggest that septum hypertrophy and diastolic dysfunction are progressive in HOCM. The mortality is independent of the severity of hypertrophy and diastolic dysfunction, and shows a close correlation with arrhythmias.