Gender-disparities in patients undergoing alcohol septal ablation for hypertrophic obstructive cardiomyopathy

Abstract

Abstract Background Alcohol septal ablation (ASA) improves symptoms in patients with hypertrophic obstructive cardiomyopathy (HOCM) but gender-disparities have only rarely been investigated. Purpose To assess gender-disparities regarding outcome and procedure-related aspects in HOCM patients undergoing ASA. Methods and results 1,367 consecutive ASAs between 2002 and 2020 were retrospectively analyzed for sex-differences. Females (47.2%) had more advanced age at the timing of ASA (66.0 years [IQR 55.0–74.0] vs. 54.0 years [IQR 45.0–62.0]; p<0.0001), had more severe symptoms (NYHA class 2.8±0.6 vs. 2.5±0.8 in males; p<0.0001) and shorter distances walked in 6-min-walk-test at baseline (359.0m [IQR 272.3–442.0] vs. 464.4m [IQR 400.0–524.0] in males; p<0.0001). The baseline interventricular septal diameter (IVSD) was higher in males (21.0mm [IQR 19.0–24.0] vs. 20.0mm [IQR 18.0–23.0] in females; p<0.0001). However, the IVSD was higher in females when it was indexed to the body-surface-area (10.9 mm/m2 [IQR 9.7–12.7] vs. 10.2 mm/m2 [IQR 9.0–11.7] in males; p<0.0001). The resting and exercise-induced left ventricular outflow tract gradients (LVOTG) were lower in females when calculated 1–4 days after ASA (resting: 20.0 mmHg [IQR 12.0–37.5] vs. 22.0 mmHg [IQR 13.0–40.0] in males; p=0.0062; exercise-induced: 55.0 mmHg [IQR 30.0–109.0] vs. 71.0 mmHg [IQR 37.0–115.0] in males; p=0.0006). At 6 months follow-up females had lower exercise-induced LVOTG (34.0 mmHg [IQR 21.0–70.0] vs. 43.5 mmHg [IQR 25.0–74.8]; p=0.0072). More females had complete heart block after ASA (20.3% vs. 13.3% in men; p=0.0005) and, hence, more females (17.4%) than males (10.4%; p=0.0002) needed a pacemaker. There were no differences regarding mortality. Conclusion Female HOCM patients had more advanced age, more severe symptoms and a higher IVSD when indexed to BSA at the timing of ASA. However, early hemodynamic response was better in females, but procedure-related complete heart block was more often found in women. Gender-disparities in clinical characteristics and procedural outcome of ASA should be taken into consideration. Funding Acknowledgement Type of funding sources: None.