Sex-based differences in anatomical and hemodynamic parameters and outcomes in patients with hypertrophic cardiomyopathy undergoing alcohol septal ablation

Abstract Background This study aimed to assess sex differences in anatomical and hemodynamic parameters, and in procedure related outcomes, in patients with hypertrophic obstructive cardiomyopathy (HOCM) undergoing alcohol septal ablation (ASA). Methods 154 patients that underwent ASA in at our university hospital, between 2009 and 2021, were retrospectively included. Anatomical and hemodynamic parameters were collected from invasive catheterization before and during ASA, and from echocardiography (ECHO) examinations at maximum one week before ASA. Follow-up was conducted one year after ASA. The parameters analyzed were left ventricular (LV) volume, basal septal wall thickness (BSWT), anterior (AML) and posterior mitral leaflet (PML) length, minimal left ventricle outflow tract (LVOT) diameter, and LVOT pressure gradient at rest, prior to ASA, and prevalence of atrioventricular block after ASA. Linear and logistic regression models were used to assess the sex differences between the parameters. Results 50% of the patients were women. At the time of ASA, women were significantly older, had lower LV volume indexed for BSA in end-diastole (44 vs. 54 ml, p<0.001) and end-systole (18 vs. 23 ml, p=0.021), longer AML length indexed for BSA (13.7 vs. 11.6 mm, p<0.001) and PML length indexed for BSA (8.8 vs. 8.1 mm, p=0.018), smaller minimal LVOT diameter (4.6 vs. 4.9 mm, p=0.042), and higher LVOT pressure gradient at rest (49.3 vs. 32.5 mmHg, p=0.014), compared with men. The median follow-up was 364 days. Atrioventricular block (II or III) was more common among women (n=20, 26%) compared with men (n=10, 13%, p=0.045). Conclusions ECHO and invasive catheterization prior to ASA showed that women with HOCM presented with less favorable anatomical and hemodynamic pre-conditions, compared with men. At follow-up, women had a greater incidence of atrioventricular block after ASA. This strongly emphasizes the need for a sex-specific approach to optimize care and improve outcomes in patients with HOCM.