Morphological Characteristics of Hypertrophic Cardiomyopathy in Korean : Echocardiographic Study

Background: Patients with hypertrophic cardiomyopathy(HCMP) may present a wide spectrum of clinical and morphological manifestations. There was little literature regarding clinical and morphological features of HCMP in Korea. Methods: 1) Study population : Among 18, 183 patients who unerwent echocardiography from June 1990 to Qctober 1993 at Yonsei cardiovascular center Echocardiography laboratory, 65 patients with HCMP were enrolled to study population. All patients with HCMP have at least onesegment of left ventricular wall measuring 17mm or more in thickness at end diastole. 2) Two dimensional echocardiography : All standard views were performed and recorded with Super VHS video tape. All records were reviewed and the maximal wall thickness was measured at video monitor by aid of electronic caliper of our echocardiographic machine. 3) Dopple echocardiography : Peak velocity of E and A wave and deceleration time were measured. The intracavitary peak systolic pressure gradient was also measured using continous wave Doppler at the site of abnomal mosaic pattern in color flow interrogation. Results: 1) Mean age of the patients was 50±15 ranging from 11 to 84 and the sex ratio was 2.3:1(male:female). 2) The type 3(involving all segments except inferior wall) was the most frequently observed in Korean(47%). 3) The mid anterior septum was the most frequently involved segment(71%) and the non-obstructive type was perdominant(78%). 4) There was 17 cases of apical HCMP and 4 cases of mid ventricular obstructive type. 5) There was no significant correlation between symptoms and dynamic obstruction. 6) The EA ratio had statistically significant difference between obstructive and non-obstructive groups probably due to mitral regurgitation. Conclusion: The type 3 was the most frequent type of HCMP in Korean and the non-obstructive type was more frequently observed than obstructive type. Among the all left ventricular segments, the mid anterior septum was most frequently involved.ope