Abstract 17705: Is Apical Hypertrophic Cardiomyopathy Distinctive Disease Entity?: Comparative Study Using Cardiac Magnetic Resonance Imaging
Background: Apical hypertrophic cardiomyopathy (HCM), which is characterized by hypertrophy of the apex of the left ventricle, is very frequently observed in patients from Asian countries and has a relatively good prognosis. Our aim was to compare the finding of cardiac resonance imaging including quantitative analysis of left ventricle (LV), frequency and distribution of stress perfusion, and delayed hyper-enhancement between patients with apical HCM and those with non-apical HCM.
Methods: Total of 200 patients with HCM (152 men and 48 women; average age: 54±13 years) had undergone cardiac magnetic resonance imaging from December 2008 to May 2010. All the MRI examinations were performed using a 1.5 T system.
Results: Among 200 patients, 64 patients (32%) were apical type and 136 patients (68%) were non-apical type. LV mass (169.27 ± 68 vs 141.05 ± 40 ml, p<0.001) and LV mass index (97.88 ± 39 vs 77.91 ± 19 ml/m2, p<0.001) were significantly increased in non-apical group than apical group. Maximal LV wall thickness (20.94 ± 4.98 vs 16.51 ± 3.77 gm, p<0.001) was significantly increased in the non-apical group than in apical group. Delayed hyper-enhancement volume and percentage of delayed hyper-enhancement were also significantly increased in the case of the non-apical group than in the case with apical group (34.24 ± 29.98 vs 13.99 ± 14.77ml, p<0.001, and 21 ± 19 vs 10 ± 11%, p<0.001, respectively). There was no difference in prevalence of stress induced perfusion defect between non-apical group and apical group (45% vs 52%, p=0.606).
Conclusion: The quantitative and qaulitative parameters of cardiac magnetic resonance imaging are different between the non-apical and apical group. These findings provide insights into pathophysiologic and clinical differences between these two distinctive subgroups of HCM.
- © 2010 by American Heart Association, Inc.