PD-1 inhibitor-associated myasthenia gravis with acute myocardial injury: a case report

Abstract Background PD-1 inhibitors can cause serious immune-related adverse events, including myasthenia gravis (MG). The occurrence of myocardial injury during immune checkpoint inhibitor therapy can pose diagnostic challenges. Case presentation A 65-year-old man with hepatocellular carcinoma developed severe PD-1 inhibitor-associated MG after receiving tislelizumab. During the acute phase, he developed acute myocardial injury, with marked hs-cTnT elevation and new ST-segment depression on electrocardiography, and non-ST-segment elevation myocardial infarction (NSTEMI) was clinically suspected. His myasthenic symptoms gradually improved with immunosuppressive therapy, whereas hs-cTnT remained elevated during follow-up. Seven months after the initial presentation, he developed an ST-segment elevation myocardial infarction due to total occlusion of the proximal left anterior descending artery and underwent percutaneous coronary intervention. Conclusion This case highlights the need to carefully evaluate the underlying cause of myocardial injury in patients with severe PD-1 inhibitor-associated MG. Persistent hs-cTnT may identify patients at increased cardiovascular risk, although the prognostic significance of this finding requires further investigation.