Misleading electrocardiographic results in patient with hyperkalaemia and diabetic ketoacidosis

Results of electrocardiography may mimic myocardial infarction in patients with severe metabolic disturbance Diabetic ketoacidosis is an important cause of morbidity and mortality in patients with insulin dependent diabetes. Around 2%-8% of all hospital admissions of diabetic patients are for ketoacidosis, and the overall mortality ranges from 2% to 10%.1 Myocardial infarction is an uncommon but well recognised precipitating cause of diabetic ketoacidosis, accounting for 1% of cases. However, myocardial infarction and congestive cardiac failure account for 28% of deaths in diabetic ketoacidosis.2 Initial baseline investigations of such patients include electrocardiography to assess possible precipitating causes and the effect of metabolic derangement on cardiac electrophysiology and rhythm. Iatrogenic hypokalaemia is a major and avoidable cause of death in diabetic ketoacidosis. However, many diabetic patients with ketoacidosis present initially with hyperkalaemia, which may affect the electrocardiographic morphology. We present a case of a patient with diabetic ketoacidosis and hyperkalaemia whose initial electrocardiogram showed a pseudoinfarction pattern. A 42 year old man with diabetes presented to accident and emergency with intermittent vomiting for three days. Over the previous two days he had been feeling increasingly tired, lethargic, polyuric, and thirsty. As he was unable to keep any food or fluids down, he had omitted two insulin injections, including one on the morning of …