Hyperoxemic Perfusion for Treatment of Reperfusion Microvascular Ischemia in Patients with Myocardial Infarction

In patients with acute myocardial infarction (AMI) primary angioplasty and stent placement is a more effective and better tolerated treatment than thrombolysis, and therefore, when logistics allow, this treatment is preferred and routinely used. However, successful reopening of an occluded coronary artery does not necessarily lead to recovery of left ventricular (LV) function. Post-AMI reduction in contractile function and ventricular remodeling may result in heart failure.There is evidence that reduced contractile function in the infarct zone is related to poor microvascular perfusion even after normalization of large-vessel flow by angiographic criteria following coronary recanalization. Failure to re-establish adequate tissue perfusion may be because of reperfusion injury, ischemia-induced microvascular damage, and plugging of the microcirculation by thrombus and plaque during mechanical recanalization. Experimental data support the hypothesis that reperfusion microvascular ischemia contributes to myocardial tissue injury over a prolonged time period.