Contemporary medical therapy, sex-specific characteristics, and outcomes of patients with non-ischemic cardiomyopathy: a prespecified interim analysis of the BIO-LIBRA study

Background: Contemporary data on characteristics, medical therapy, and outcomes in non-ischemic cardiomyopathy (NICM) with implantable cardioverter defibrillator (ICD) or cardiac resynchronization therapy defibrillator (CRT-D) are lacking, and the role of sex remains unexplored due to historical low enrollment of females in device trials. The purpose of this pre-specified interim analysis of the BIO-LIBRA study was to assess characteristics, medical therapy, and ventricular tachyarrhythmias (VT/VF) or mortality at 12 months in NICM patients with ICD or CRT-D, by sex. Methods: In this multicenter, prospective, registry study, we recruited patients with primary prevention ICD or CRT-Ds with Home Monitoring®, aiming for 40% female enrollment, utilizing specific recruitment tools. Patients were assessed for the primary endpoint of device-treated VT or VF every 6 months. This study is registered with ClinicalTrials.gov (NCT03884608). Findings: From May 9, 2019 to October 1, 2021, we enrolled 1000 patients, including 475 (47.5%) females, 30.4% non-white, and 9.2% Hispanic/Latino patients. Beta-blockers were prescribed in 92%, ACE-Inhibitor/ARB in 80%, ARNI in 39%, and SGLT2 in 6% at enrollment with increase in SGLT2 use over time. Diuretics were more frequently prescribed in females. Females had a 52% lower risk of VT/VF or death as compared to men through 12 months (HR = 0.49, 95% CI: 0.31-0.78, p = 0.003), driven by a 54% lower risk of VT/VF (HR = 0.46, 95% CI: 0.25-0.85, p = 0.003), even after adjustments for LVEF or QRS duration. No significant differences were reported by ICD vs. CRT-D. Interpretation: In a contemporary cohort of patients with NICM and ICD/CRT-D, we report an increased enrollment of females and minorities, an increase in the use of novel guideline-directed medical therapy (GDMT) over time, and a lower risk of ventricular arrhythmias or death in females as compared to men at one year. Funding: BIOTRONIK Inc.