Abstract 13825: Clinical and Echocardiographic Outcomes Associated With Early Initiation of Beta Blockers Use Among Patients With Recently Diagnosed Non-Ischemic Cardiomyopathy Treated With a Wearable Cardioverter Defibrillator

Introduction: Beta-blocker (BB) therapy was shown to improve clinical outcomes among heart failure patients with reduced ejection fraction. However, there are limited data on the efficacy of BB use among patients with recently diagnosed non-ischemic heart cardiomyopathy (NICM) who are treated with the wearable cardioverter defibrillator (WCD) until a decision on the need for an ICD is made. Aim: Determine if BB use is associated with improved outcomes in patients with NICM treated with the WCD. Methods: The study population comprised 1195 patients with recently diagnosed NICM enrolled in the prospective WEARIT-II Registry. Clinical data, arrhythmia events, ICD implantation, and improvement in left ventricular ejection fraction (LVEF) were captured. Multivariate logistic regression was used to estimate the odds ratio (OR) of LVEF improvement to >35% by BB usage. The risk of death at 1-year by BB use was assessed using a multivariate cox-proportional hazards modeling. Results: Patients treated with BBs at baseline were more likely to experience an improvement in LVEF to >35% that patients who did not receive treatment with BB (43% vs 29%, respectively; adjusted OR=1.67 95% CI [1.15-2.41] p=0.007; Figure: panel A and were less likely to receive an ICD at the end of the WCD use (37% vs 47%; adjusted OR=0.64 95% CI [0.46-0.90] p=0.024; Figure: panel B). At 12 months of follow-up the probability of death was significantly lower among patients who received BB therapy during WCD use vs. those who did not.,(p=0.007 Figure: panel C), corresponding to a significant 59% lower risk of death at one year associated with early BB use (adjusted HR=0.41 95% CI [0.21-0.80] p<0.01). Conclusions: Among patients newly diagnosed NICM who are treated with a WCD until a decision on the need for an ICD is made, early initiation of BB is independently associated with a greater likelihood of improvement in EF, a lower probability of needing an ICD at end of WCD use, and a lower risk of death at 1-year.