Hemodynamics of microvascular dysfunction in patients with anterior wall acute myocardial infarction.

This study investigated whether the no-reflow phenomenon in acute myocardial infarction (AMI) is associated with an increase in coronary zero flow pressure (ZFP), a decrease in coronary arterial conductance, or both phenomena. Coronary blood flow velocity and pressure were measured with a Doppler guidewire and a pressure wire, respectively, during vasodilation with adenosine triphosphate after coronary intervention. The data indicate that the no-reflow phenomenon is not necessarily associated with a decrease in coronary arterial conductance but with an increase in ZFP. Greater ZFP is associated with more severe microvascular dysfunction and worse functional outcomes in patients with AMI.