Clinical characteristics, treatment and prognosis of pembrolizumab induced myocarditis.

To explore the regularity and clinical characteristics of pembrolizumab induced myocarditis, and to provide a reference for the diagnosis and treatment of myocarditis. Clinical reports of pembrolizumab induced myocarditis were collected by searching the database as of May 31, 2025. Clinical data were extracted and analyzed statistically. A total of 97 patients were enrolled in the study, with a median age of 70 years (range 25, 89), of which 53(54.6%) were male. The median time for diagnosis of myocarditis was 25 days (range 3, 4050). The common clinical symptoms were dyspnoea (23.7%), shortness of breath (16.5%), and thoracic pain (13.4%). Myositis and/or myasthenia gravis occurred in 43.3% of the patients. These patients with myocarditis may be accompanied by abnormalities in myocardial biomarkers, electrocardiograms, cardiac magnetic resonance and echocardiograms. After the patients discontinued pembrolizumab and received steroid-based immunotherapy, 72.2% of the patients recovered and 26.8% of the patients died. Myocarditis is a rare and fatal immune-related adverse event of pembrolizumab. Cardiac biomarkers, electrocardiograms and echocardiograms should be monitored during the use of Pembrolizumab. Cardiac magnetic resonance or myocardial biopsy can be used to further confirm myocarditis.