Myocardial infarction in the neonate with normal heart and coronary arteries.

Myocardial infarction is rarely recognized in the newborn. We report two cases in which the infant had a normal heart with normal coronary arteries. A review of previously described cases suggests that the most frequent cause of neonatal myocardial infarction is coronary artery occlusion secondary to paradoxical thromboembolization. It is speculated that infarction also can result from coronary hypoperfusion in asphyxiated infants. This report serves to remind the clinician that myocardial infarction can occur in the neonatal period and that an ECG should be obtained when evaluating a newborn with acute onset of shock.