Morphological and Electrical Characteristics in Patient with Hypertrophic Cardiomyopathy: Quantitative Analysis of 864 Korean Cohort

PURPOSE: Although several studies have reported the morphological and electrical characteristics in patients with hypertrophic cardiomyopathy (HCM), comparison between asymmetric and apical HCM has not been investigated in a reasonably sized cohort. MATERIALS AND METHODS: Echocardiography and electrocardiography were quantitatively analyzed in patients with HCM in a Korean tertiary referral center. RESULTS: Of 864 patients (mean age 55.4±14.2 years, 68.9% men), 255 (29.5%) patients had apical HCM, 553 (64.0%) patients asymmetric HCM, and 56 (6.4%) patients mixed type HCM. In echocardiographic evaluations, about three quarters of patients (75.8%) had left atrial enlargement. Left ventricular (LV) dilatations and systolic dysfunction were observed in 6.1% and 2.4%, respectively. QRS widening, PR prolongation, and pathologic Q wave are frequent in patients with asymmetric HCM, while LV strain is frequent in patient with apical HCM. The prevalence of J-point elevations (9.4% in inferior, 2.2% in lateral leads) were substantially higher than that in general population. Giant negative T wave was observed in 15.0% of total patients (32.2% in apical, 6.2% in asymmetric, 25% in mixed type). There was no significant correlation between the thickness of the apical wall and the amplitude of T wave inversion (r=-0.005, p=0.71). CONCLUSION: In a large cohort of HCM including apical type, repolarization abnormalities, including early repolarization and QT prolongation as well as LV strain, were significantly observed. T wave inversion was not appropriate for screening of HCM and not correlated with apical wall thickness.