Clinical and morphological features of hypertrophic cardiomyopathy in Korean patients.

Thirty three cases of hypertrophic cardiomyopathy (HCMP) were reviewed to estimate the relative frequencies of the subtypes of HCMP and to clarify whether there is any racial difference in clinical and morphological features of HCMP. The diagnosis was made by echocardiography, cardiac catheterization and left ventriculography. Twenty four patients underwent coronary angiogram. Numbers of cases by the types of HCMP were 20 (61%) with asymmetrical septal hypertrophy (ASH), 11 (33%) with apical hypertrophy (APH) and 2 (6%) with midventricular hypertrophy (MVH). Mean ages of the patients with APH, ASH and MVH were 54, 46 and 31 years respectively, and the differences were statistically significant (p less than 0.05). The giant negative T wave on electrocardiogram was seen in 4 patients (20%) of ASH and 5 patients (45%) of APH. On echocardiogram mean ratio of interventricular septal to left ventricular posterior wall thickness was 1.9 in ASH, 1.2 in APH and 1.6 in MVH, and the differences were statistically significant (p less than 0.05). All patients with APH showed "spade of ace" deformity in left ventriculography. Coronary angiograms were normal in all patients who had the procedure. Our study showed high frequency of APH of which characteristics were similar to those of the Japanese type APH.