A 36-year-old woman without overt coronary risk factors was admitted to hos
pital with coma about 9 hours after mass self-injection of insulin (1,500 u
nits). Laboratory investigation revealed severe hypoglycemia and hyperinsul
inemia. During the treatment of her hypoglycemia, circulatory collapse occu
rred. The EGG, echocardiogram, and elevation in troponin T suggested a diag
nosis of myocardial infarction. Although the patient became apallic and dev
eloped systemic spasticity due to hypoglycemic brain damage, her hemodynami
cs improved with supportive care alone. Coronary angiography and myocardial
scintigraphy performed later demonstrated a broad area of myocardial damag
e despite intact coronary artery circulation. The authors hypothesize that
temporary coronary arterial narrowing or coronary arterial vasospasm induce
d by severe hyperinsulinemia contributed to the pathogenesis of the myocard
ial infarction. The possibility of myocardial infarction should be consider
ed in patients with acute insulin poisoning.