Clinicopathologic features of hypertrophic cardiomyopathy managed by cardiac transplantation.

Clinical records, electrocardiographic, echocardiographic, hemodynamic and radionuclide data, and the operatively excised hearts were reviewed in 10 patients (aged 19 to 46 years, mean 35) who had cardiac transplantation for hypertrophic cardiomyopathy. Severe congestive heart failure unassociated with outflow obstruction was the indication for transplantation in 9 patients. During a pretransplantation period ranging from 45 to 312 months (mean 137) in these 9 patients, pulmonary artery wedge pressure increased from 19 +/- 9 to 27 +/- 7 mm Hg, left ventricular ejection fraction decreased from 51 +/- 11% to 41 +/- 1%, left ventricular end-diastolic dimension increased from 42 +/- 6 to 48 +/- 4 mm, and total 12-lead QRS voltage decreased from 209 +/- 50 to 156 +/- 41 mm. In these 9 patients, the explanted hearts had dilated left ventricular cavities, and 8 had left ventricular scars without significant narrowing of the epicardial coronary arteries. The tenth patient had a nondilated left ventricular cavity and had transplantation because of recurrent, refractory syncope. Of the 10 patients, 3 died within the first month, and another died 8 months after transplantation. The remaining 6 patients have survived 20 to 54 months (mean 39) after transplantation and are in functional class I or II.