Mimics and Chameleons: A Patient with Accidental Hypothermia and Myocardial Infarction

Background Accidental hypothermia is an unintentional drop in core temperature below 35 °C, typically resulting from exposure to cold environmental conditions. Clinical presentations may vary widely depending on the severity of hypothermia and the presence of coexisting conditions complicating diagnosis and treatment. We report a case of accidental hypothermia caused by environmental exposure and associated with cardiogenic shock from a myocardial infarction with complete heart block. Case Presentation A group of ski tourers found a 62-y-old male skier at 3000 m in severe distress with abdominal pain, shivering, and profound exhaustion. On arrival at a mountain hut, he was agitated, then became unconscious and bradycardic with a weak femoral pulse. Once advanced medical equipment reached the hut, a 12-lead electrocardiogram showed an inferior ST-elevation myocardial infarction (STEMI) with complete third-degree atrioventricular block and a ventricular escape rhythm. The first measurable axillary temperature was 32.2 °C. Consciousness progressively improved, but bradycardia persisted during rewarming. The patient was evacuated 6 h after the diagnosis of acute STEMI. He underwent percutaneous coronary intervention and was successfully treated with a stent. Conclusions This case illustrates that hypothermia and environmental factors can complicate the diagnosis of atypical presentations of life-threatening conditions, such as STEMI, and how unexpected clinical findings not fully explained by hypothermia may indicate the presence of an underlying condition. In such situations, hypothermia staging systems should be used with caution. Early electrocardiography, awareness of cognitive biases, and the use of safe rewarming practices are essential to ensure timely diagnosis and prevent complications.