Regional myocardial infarction of low-flow type in a neonate with tricuspid atresia.

Clinical and anatomical data are presented on a neonate with tricuspid atresia, who died at 16 hours with a regional, nontransmural myocardial infarcti after clinical documentation of akinesis. A partially occlusive intimal lesion associated with acute angulation of the right coronary artery was noted in an area of fibrosis that included the atretic tricuspid valve. Low-flow myocardial infarction was found in the posterior part of the left ventricle in an area supplied by the right coronary artery distal to the arterial lesion.