Cardiogenic shock secondary to immune checkpoint inhibitor associated myocarditis

Immune checkpoint inhibitors have transformed the treatment for multiple cancers and are increasingly used in recent years, but they can cause potentially life-threatening cardiac toxicity. We report a case of a 64-year-old gentleman who presented to the Emergency Department with symptoms of fatigue and breathlessness whilst receiving treatment with an immune checkpoint inhibitor, pembrolizumab, for cholangiocarcinoma. He was found to be in cardiogenic shock with an abnormal electrocardiogram and elevated cardiac troponin at presentation. Echocardiogram demonstrated severely impaired right and left ventricular function. Computed tomography pulmonary angiography and invasive coronary angiography excluded pulmonary embolism and acute myocardial infarction, respectively, and he was diagnosed with immune checkpoint inhibitor associated myocarditis. He was treated with high-dose methylprednisolone and a dobutamine infusion. Within days, his troponin and C-reactive protein levels decreased, and his left ventricular function improved. He was established on heart failure therapies and discharged from hospital 12 days later.