Successful Steroid Pulse Therapy in Suspected Immune Checkpoint Inhibitor-Associated Myocarditis With Isolated...

The optimal timing and indications for corticosteroid therapy in patients with suspected immune checkpoint inhibitor (ICI)-associated myocarditis and isolated cardiac troponin (cTn) elevation remain unclear.

A 67-year-old man with recurrent esophageal cancer developed marked cTnI elevation (6,714 pg/mL) 3 weeks after the first nivolumab-ipilimumab cycle. The patient was asymptomatic but was suspected to have ICI-associated myocarditis. Steroid pulse therapy was promptly initiated, and after 5 days, cardiac magnetic resonance imaging confirmed myocarditis. His cTnI levels normalized within 2 weeks, and cardiac function was preserved.

This case highlights the potential benefits of immediate steroid pulse therapy in asymptomatic patients with suspected ICI myocarditis. Treatment before diagnostic confirmation may prevent disease progression.

Even in asymptomatic patients, early corticosteroid therapy should be considered for isolated cTn elevation suggesting ICI-associated myocarditis. Institutional awareness and preparedness for early intervention are crucial for effective allocation of short-term intensive medical resources.