Myocarditis With Quetiapine

Mr. A, a 35-year-old man with paranoid schizophrenia, was admitted to a psychiatric hospital for the first time. Initially, he was medicated with benperidol and lorazepam, which led to the remission of acute psychosis. He developed extrapyramidal symptoms, and quetiapine, 800 mg/day, was introduced. On admission, a first-degree atrioventricular block and an incomplete right bundle-bunch block were diagnosed. No history of heart disease or cardiac risk factors was found.

During Mr. A’s first 2 months of monotherapy with quetiapine, 600 mg/day, mild eosinophilia (6% eosinophilia cells), thrombocytopenia (138 platelets/nl), and leukopenia (3.9 leukocytes/nl) developed. In the next 2 months, when Mr. A was still taking quetiapine without concomitant medications, a routine workup revealed high levels of creatinine kinase (107 U/liter), troponin (7.9 mg/liter), and C-reactive protein (75.9 mg/liter). In the last 4 days before the increase in his creatinine kinase level, Mr. A had a temperature of 37.8°C and reported nasal congestion with watery discharge, fatigue, and myalgia in the absence of chest pain.

Myocarditis was diagnosed on the basis of transient and ubiquitous ST wave elevation on ECG and elevation of cardiac enzyme levels. Nevertheless, myocardial infarction could not entirely be ruled out in the absence of catheterization. Mr. A’s ECG showed normal global pump function and no pericardial effusion; long-term ECG revealed no arrhythmia.

Since the origin of Mr. A’s myocarditis was unknown, quetiapine therapy was immediately withdrawn. He was treated with metoprolol, 10 mg/day, and ramipril, 2.5 mg/day. A decrease in Mr. A’s levels of troponin and creatinine kinase was observed in the next 4 days, and he was considered cardiologically stable. Within 2 weeks after discontinuation of quetiapine, his eosinophilia, thrombocytopenia, and leukopenia resolved. Amisulpride was initiated without recurrence of psychiatric or cardiac symptoms.