Effect of alpha-adrenergic stimulation on regional contractile function and myocardial blood flow with and without ischemia.

Abstract

These results indicate the selective vasoconstriction in outer wall layers during ischemia mediated by either alpha 1- or alpha 2-receptors can cause a decrease in regional contractile function despite unchanged subendocardial blood flow and improved subendocardial-to-subepicardial flow ratio. This suggests an adverse effect of alpha-adrenergic vasoconstriction during ischemia in this coronary perfusion pressure-controlled canine model.