Impact of Coronary Artery Anatomy on Clinical Course and Prognosis in Apical Hypertrophic Cardiomyopathy: Analysis of Coronary Angiography and Computed Tomography

BACKGROUND AND OBJECTIVES Apical hypertrophic cardiomyopathy (AHCM) is an uncommon variant of hypertrophic cardiomyopathy with a relatively benign course. However, the prognostic factors of AHCM-particularly those associated with coronary artery disease (CAD) and its anatomical subtypes-are not well known. SUBJECTS AND METHODS We enrolled 98 consecutive patients with AHCM who underwent coronary angiography or coronary computed tomography scanning at two general hospitals in Korea from January 2002 to March 2012. Patient charts were reviewed for information regarding cardiovascular (CV) risk factors, symptoms, and occurrence of CV events and/or mortality. We also reviewed echocardiographic data and angiography records. RESULTS The mean age at the time of enrollment was 61.45±9.78 years, with female patients comprising 38.6%. The proportions of mixed and pure types of AHCM were 34.4% and 65.6%, respectively. CAD was found in 31 (31.6%) patients. The mean follow-up period was 53.1±60.7 months. CV events occurred in 22.4% of patients, and the mortality rate was 5.1%. The mixed-type was more frequent in CV event group although this difference was not statistically significant (50% vs. 30%, p=0.097). The presence of CAD emerged as an independent risk factor for CV events in univariate and multivariate Cox regression analysis after adjusting for other CV risk factors. CONCLUSION Coronary artery disease is an independent risk factor for CV events in AHCM patients. However, AHCM without CAD has a benign natural course, comparable with the general population.