A？young man with exertional chest discomfort

In this case we present a 43-year-old athletic male, nonprofessional cyclist with unremarkable medical history. He had been admitted to the emergency department because of chest discomfort, dizziness, heavy sweating and nausea after cycling 40？km in extreme heat (local temperature 41.5 degrees Celsius). Physical examination revealed a Glasgow Coma Scale score of 15, and he was haemodynamically stable. The laboratory results showed: creatine kinase 870？IU/l, creatine kinase-MB 12？IU/l, troponin T 16？ng/ml, and creatinine 1.6？mg/dl. Out-of-hospital electrocardiogram taken at first medical contact is shown in Fig. 1