Sudden death case of single coronary artery with special reference to the effect of ischemia on actomyosin.

A normal single left coronary artery was found in a high school boy who died suddenly after Rugby football practice. He had an infarct lesion in the posterior wall where there was no perfusion because of the absence of the right coronary artery. There was no significant lesion in the anterior wall except for contraction band necrosis. Myoglobin diffusion paralleled the extent of necrosis. The case was useful in evaluating the effects of ischemia on a human subject because variations due to personality and postmortem changes were not involved. Actomyosin ATPase activity was not different among the various infarct and non-infarct regions examined except in one infarct region where it was higher.