Sex Disparities in the Use and Outcomes of Septal Reduction Therapies for Obstructive Hypertrophic Cardiomyopathy

Background: Data are limited that examine potential sex-based disparities in the utilization and complications of septal reduction therapy (SRT) in patients with obstructive hypertrophic cardiomyopathy. Our aim was to assess the use and in-hospital outcomes of SRT, according to sex. We performed a retrospective cohort study using the 2017-2019 National Inpatient Sample database. Adult patients with obstructive hypertrophic cardiomyopathy were identified. Methods: We assessed the use of SRT (surgical septal myectomy and alcohol septal ablation), according to sex. In those who underwent SRT, rates of in-hospital mortality, pacemaker implantation, implantable cardioverter defibrillator (ICD) implantation, ischemic stroke, major bleeding, and pericardial complication were assessed. All outcomes were compared between groups using inverse probability of treatment weighting (IPTW), adjusting for demographics, comorbidity burden, and hospital characteristics. Results: In total, 72,680 weighted hospitalizations (median age: 67 years [range: 57-77]; 61% female patients) were included, and only 5.9% of patients underwent SRT. After IPTW adjustment, female patients were more likely to undergo SRT (adjusted risk ratio [aRR] 1.18, 95% confidence interval [95% CI] 1.03-1.36) and alcohol septal ablation (aRR 1.38, 95% CI 1.04-1.83). Likewise, female patients received pacemaker implantation more often (aRR 1.96, 95% CI 1.10-3.50) and ICD implantation (aRR 0.58, 95% CI 0.34-0.99) less frequently, compared with male patients. No differences were present in rates of surgical septal myectomy, in-hospital mortality, ischemic stroke, major bleeding, and pericardial complication between groups. Conclusions: Our results suggest that female patients were slightly more likely to undergo SRT, especially alcohol septal ablation. In-hospital mortality and postprocedural complications were similar between the sexes, but women received more pacemaker implantation and less ICD implantation.