Importance: Immune checkpoint inhibitors (ICIs) are a class of immunotherapies that have significant clinical efficacy in treating many cancer types, but they are also associated with systemic effects, including myocarditis.

Objective: This review describes potential mechanisms underlying ICI-associated myocarditis; data on epidemiology, including possible risk factors; diagnostic criteria for ICI-associated myocarditis; and recommendations for managing ICI-associated myocarditis.

Review: This paper is a narrative literature review that summarizes existing literature to increase awareness of ICI-associated cardiotoxicities, including myocarditis.

Findings: Reported cardiovascular adverse events include myocarditis, cardiomyopathy, arrhythmias, pericarditis, vasculitis, atherosclerotic cardiovascular events, Takotsubo syndrome, and venous thromboembolism. Myocarditis is associated with the highest risk of morbidity and mortality.

Conclusions: With increasing use of ICIs, there is an urgent need for greater awareness and understanding of ICI-associated myocarditis. Clinicians need to recognize the diagnostic criteria and develop current treatment recommendations for ICI-associated myocarditis given the condition’s variable clinical presentation and potential fulminant course.