Immune Checkpoint Inhibitor Myocarditis and Left Ventricular Systolic Dysfunction.

Abstract

Background: Immune checkpoint inhibitors (ICIs) have transformed cancer treatment, but ICI myocarditis (ICI-M) remains a potentially fatal complication. The clinical implications and predictors of left ventricular ejection fraction (LVEF) <50% in ICI-M are not well understood. Objective(s): The aim of this study was to identify factors associated with LVEF =50% at the time of hospitalization for ICI-M. A secondary objective was to evaluate the relationship between LVEF and 30-day all-cause mortality. Method(s): The International ICI-Myocarditis Registry, a retrospective, international, multicenter database, included 757 patients hospitalized with ICI-M. Patients were stratified by LVEF as reduced LVEF (=50%) on admission. Cox proportional hazards models were used to assess the associations between LVEF and clinical events, and multivariable logistic regression was conducted to examine factors linked to LVEF. Result(s): Of 757 patients, 707 had documented LVEFs on admission: 244 (35%) with LVEF =50%. Compared with patients with LVEF >=50%, those with LVEF =50%. Compared with patients with LVEF >=50%, those with LVEF =50%. Compared with patients with LVEF >=50%, those with LVEF =50%. Compared with patients with LVEF >=50%, those with LVEF ², and were more likely to have received chest radiation (24.2% vs 13.5%; P , and were more likely to have received chest radiation (24.2% vs 13.5%; P =50%. LVEF <50% was marginally associated with 30-day all-cause mortality (unadjusted log-rank P = 0.062; adjusted for age, cancer types, and ICI therapy, HR: 1.50; 95% CI: 1.02-2.20). Conclusion(s): Dyspnea, time from ICI initiation, a history of heart failure, and prior cardiotoxic therapy may be predictors of an initial LVEF <50% in patients with ICI-M. Copyright © 2025 The Authors