Immune checkpoint inhibitor-associated myocarditis: from pathophysiology to rechallenge of therapy - a narrative review

Even if immune checkpoint inhibitors have revolutionized the landscape of cancer therapy, their use may be complicated by immune-related adverse events. Among these, myocarditis is the most severe complication. The clinical suspicion often arises after clinical symptoms onset and increase in cardiac biomarkers or electrocardiographic manifestations. Echocardiography and cardiac magnetic resonance imaging are recommended for each patient. However, since they may be misleadingly normal, endomyocardial biopsy remains the gold standard for establishing the diagnosis. Until now, treatment has been based on glucocorticoids even if increasing interest has risen in other immunosuppressive agents. Although myocarditis currently imposes immunotherapy discontinuation, case reports have suggested a safety rechallenge in low-grade myocarditis paving the way for further studies to respond to this unmet clinical need.

Automated summary

Although immune checkpoint inhibitors have greatly improved cancer therapy, they can lead to immune-related adverse events, with myocarditis being the most severe complication. Clinical suspicion arises from symptoms and increases in cardiac biomarkers or electrocardiographic manifestations. While echocardiography and cardiac magnetic resonance imaging are recommended, endomyocardial biopsy remains the gold standard for diagnosis. Treatment currently relies on glucocorticoids, but interest in other immunosuppressive agents is growing. Some case reports suggest the safety of rechallenging low-grade myocarditis, highlighting the need for further studies in this area.