부산대학교 도서관

A 68–year–old Caucasian female presented to the ED with cardiac chest pain and dyspnea. The patient had a history of arterial hypertension and was equipped with a biventricular pacemaker due to atrial fibrillation with low ventricular response. She had recently been diagnosed with metastatic melanoma and initiated treatment with nivolumab and ipilimumab two weeks prior. Troponin levels were elevated (700 ng/ml), and no ST–segment elevation was observed on the electrocardiogram (ECG). In suspicion of NSTEMI–ACS, coronary angiography was performed, revealing an intact epicardial coronary circulation without stenotic lesions. The echocardiogram showed borderline left ventricular systolic function (EF 50%), and the right ventricle exhibited initial signs of reduced systolic function (TAPSE, 15 mm; S RV, 9.5 m/s). The following day, there was a deterioration in hemodynamics and respiratory exchange, with evidence of apical and mid–distal interventricular septum hypokinesia of the left ventricle (EF 40%) and dilated right ventricle (BD 4.8 cm; MD 4 cm) with severely reduced systolic function (TAPSE 10 mm, S RV 7 m/s, FAC, 20%), and severe tricuspid regurgitation. Urgent computed tomography pulmonary angiography (CTPA) excluded pulmonary embolism. Additionally, there was a new troponin increase (5000 ng/ml) and elevated hepatic biomarkers. The clinical picture raised suspicion of myocarditis related to immune checkpoint inhibitor therapy. Corticosteroid therapy was initiated with a daily administration of methylprednisolone 1000 mg. Diagnostic confirmation was sought through autoimmune panel and viral marker assessments, which yielded negative results. Endomyocardial biopsy (EMB) revealed CD4 and CD8–positive lymphocytic infiltration and myocardial necrosis. Despite initial clinical improvement, an arrhythmic storm developed. Despite treatment with a defibrillator, intravenous antiarrhythmic therapy (beta–blocker, amiodarone, and lidocaine), and sedation, the patient unfortunately succumbed. Immune checkpoint inhibitors (ICIs) have been revolutionary in the treatment of many solid tumors. However, the dysregulation of immune mechanisms can rarely (2%) lead to autoimmune events involving multiple organs. Myocarditis, despite optimal treatment, is characterized by a mortality rate exceeding 50%, representing a significant challenge in the Intensive Care Unit.