Clinical features and long-term outcome comparison of patients with midventricular obstructive hypertrophic cardiomyopathy and apical hypertrophic cardiomyopathy

Abstract

To compare the clinical features and long-term outcome of patients with midventricular obstructive hypertrophic cardiomyopathy (MVOHCM) and patients with apical hypertrophic cardiomyopathy (AHCM) in China. This retrospective study analyzed clinical data of 66 patients with MVOHCM and 263 patients with AHCM from a consecutive single-center cohort consisting of 2 413 patients with HCM. The clinical features, cardiovascular mortality and morbidity were compared between the two groups. Compared with the AHCM, patients in the MVOHCM group was younger and more likely to be symptomatic over a mean follow-up of 7 years. The proportion of MVOHCM and AHCM were 2.7% (66/2 413) and 10.9% (263/2 413) (P < 0.001), respectively, in this cohort. Cardiovascular mortality of the two groups were 13.6% (9/66) and 0.8% (2/263) (P < 0.001), and cardiovascular morbidity of the two groups were 53.0% (35/66) and 14.4% (38/263) (P < 0.001). MVOHCM is rarer, but the clinical manifestations and long-term outcomes are worse compared with AHCM in this patient cohort.