[Natural course of hypertrophic cardiomyopathy: clinical, hemodynamic and echocardiographic features in the end stage].

We investigated the natural course of 59 patients with hypertrophic cardiomyopathy (HCM) in follow-up periods of one to 13 years and analyzed the clinical, hemodynamic and echocardiographic parameters to determine the factors influencing the prognosis. Among these patients, 44 (75%) remained stable in a compensated condition with or without medications. Five patients died suddenly and two died of congestive heart failure. Heart failure developed in another eight. At the initial evaluation, these 15 patients had high left ventricular end-diastolic pressure (mean: 22 +/- 8 mmHg) significantly higher than that of 44 compensated patients (mean: 13 +/- 6 mmHg, p less than 0.001). There were no differences in age at the initial evaluation between compensated and end stage groups. Atrial fibrillation occurred persistently in three and transiently in two among ten patients with heart failure during follow-up periods. Ventricular dimensions and systolic function did not statistically differ between the two groups. However, six patients with heart failure had cavity dilatation and deteriolated ventricular contractile function at the initial evaluation. Four of them did not show any change in left ventricular hypertrophy, but the regional thinning of the wall was observed in the remaining two. There were no characteristic features to predict sudden death in the clinical, hemodynamic or echocardiographic parameters. Thus, increased left ventricular end-diastolic pressure, atrial fibrillation, left ventricular dilatation and the regional thinning of the left ventricular wall are useful predictive markers for poor prognosis in HCM.