Apical hypertrophic cardiomyopathy- not so benign after all?
I Chung, P J FrancisAbstract
Background
Hypertrophic cardiomyopathy (HCMP) is the commonest cardiomyopathy and we have described previously that differences in the clinical outcomes depending on the phenotypes.
Methods
360 patients who were diagnosed with HCM at a teaching hospital from 1995 to 2025 with a mean follow-up duration of 7.36 ±4.37 years. We compare the effect of different phenotypes, apical (n=199) and non-apical (n=161) HCMP on clinical outcomes of patients. Continuous variables were compared by Student t tests and categorical variables compared by use of the Fisher exact test. Statistical significant difference was denoted as p<0.05. Clinical endpoints include life threatening ventricular arrhythmias (VAs)/ sudden cardiac death (SCD), atrial fibrillation, stroke, hospitalisations for heart failure (HHF), cardiovascular and all cause mortality.
Results
Mean age 69.98±13.45, 62 % men, women were older, 75.15 ±12.30 vs 66.84 ±13.18 respectively. Hypertension 69%, diabetes mellitus 19%, ischaemic heart disease 24%, device therapy 3.8%, LDL 2.70 ±1.10 mmol/L. All cause mortality 14.7%, cardiovascular death 7%, HHF 23%. Of the 199 apical HCMP, there were 7 apical aneurysms (3.5%). There was significantly more VAs/ SCD in non-apical HCMP (n=8, p=0.012) and there were no statistical significant difference in atrial fibrillation, stroke or HHF between the two groups (p>0.05).
Conclusions
Life threatening arrhythmic risk is statistically higher in non-apical HCMP but incidence of atrial fibrillation, stroke and hospitalisation for heart failure same between apical and non-apical HCMP.