Management and Surveillance of Immune Checkpoint Inhibitor Myocarditis: Managing the Aftermath: JACC CardioOncology State-of-the-Art Review.

Immune checkpoint inhibitor (ICI)-associated myocarditis remains one of the most serious immune-related adverse events and can present major challenges after hospital discharge. Although guidelines and expert consensus statements have addressed diagnostic and management strategies in the acute phase, there is a paucity of evidence for post-discharge management and how to address recrudescence of symptoms and/or biomarkers suggesting rebound myocarditis. This review synthesizes evidence on the pathophysiology of ICI myocarditis, including the T cell-macrophage inflammatory loop that sustains smoldering disease, and provides a framework for outpatient management. We address steroid tapering strategies, the taper-flare phenomenon, and evidence for second-line agents and emerging therapies. Practical guidance is provided for biomarker surveillance, cardiac imaging protocols, antimicrobial prophylaxis, and the balance between immunosuppression and infection risk. This review aims to highlight and address significant gaps in cardio-oncology practice by offering clinicians an evidence-informed roadmap for managing this complex patient population.