Abstract 16047: Clinical Difference Between Extended and Pure Apical Type of Apical Hypertrophic Cardiomyopathy
Introduction: Apical hypertrophic cardiomyopathy (HCM) is a type of hypertrophic cardiomyopathy that is considered to show favorable prognosis compared to other types in general. With the increase in use of cardiac magnetic resonance imaging (CMR), it has been able to evaluate the extent of apical hypertrophy among the patients with apical HCM.
Hypothesis: We sought to find out the difference between the extended type and the pure apical type of apical HCM.
Methods: Sixty-nine consecutive subjects who received CMR at our institute under the diagnosis of apical HCM by echocardiography were included in this study. The subjects were divided into two groups. When the hypertrophy was confined only to the 4 left ventricular apical segments, the subject was included in the pure apical group (N=32). The second group consisted of subjects whose apical hypertrophy was extended to at least one of the midventricular 6 segments, hence extended apical group (N=37). Clinical and CMR parameters were evaluated and compared between the two groups.
Results: There were no significant differences in age, gender, history of syncope, NYHA class, presence of atrial fibrillation, or family history of sudden cardiac death or HCM. There were no differences in non-sustained ventricular tachycardia on 24-hour ECG or abnormal hemodynamic response to exercise either. In the extended apical group, the frequency of presence of late Gadolinium enhancement, (35 (94.6%) vs. 23 (71.9%), p = 0.02), left ventricular mass index, (78.90±19.78 vs. 69.24±12.71, p = 0.03) and presence of dynamic left ventricular cavity obstruction (18 (48.6%) vs. 3 (9.4%), p =0.001) were significantly higher compared to the pure apical group. Notably, there were 14 cases of apical pouching or aneurysmal change (20.3%) which were found only in the extended apical group.
Conclusions: The extended type of apical hypertrophy in apical HCM demonstrates a higher rate of potentially serious findings for the prognosis of the disease compared to the pure apical type. This group should be considered separately among the apical HCM patients and may need special attention.
Author Disclosures: S. Lee: None. S. Chang: None. S. Park: None. J. Choi: None. S. Park: None. E. Kim: None. G. Lee: None. S. Kim: None. E. Cho: None. Y. Choe: None. J.K. Oh: None.
- © 2014 by American Heart Association, Inc.