Hypertrophic cardiomyopathy in adult patients. Clinical course and prognostic factors in 119 patients

BACKGROUND AND OBJECTIVE: The purpose of this study was to characterize adult patients with hypertrophyc cardiomyopathy (HCM), to compare their mortality with that of the general population and to establish a prognosis based on clinical and noninvasive techniques. PATIENTS AND METHOD: One hundred nineteen consecutive patients (60 women, mean: 52 [12] years) with HCM were prospectively studied by ECG, Holter, echo-Doppler, exercise testing, myocardial perfusion SPET and radionuclide ventriculography. Prognostic variables included clinical data and parameters derived from these noninvasive techniques. RESULTS: During a mean follow-up of 10 [6.7] years, 7 patients (5.8%) died of cardiovascular causes (4 cardiac failure and 3 sudden death). The annual mortality rate was 0.6% and the actuarial survival curve for patients with HCM was significantly worse compared with the expected survival curve derived from the general population after adjustment for age and sex (p = 0.008). The presence of atrial fibrillation (p = 0.04), moderate or severe mitral regurgitation (p = 0.02), dynamic gradient > 50 mmHg (p = 0.02), left atrial diameter > 45 mm (p = 0.02), and interventricular septal thickness > 25 mm (p = 0.04) were all predictive of mortality. CONCLUSIONS: The mortality rate of adult patients with HCM is significantly higher than that expected for the general population and heart failure and sudden death are almost evenly distributed as a cause of death in these patients. Atrial fibrillation, magnitude of mitral regurgitation, dynamic gradient, left atrial dilatation and interventricular septal thickness are the main predictors of death.