Influence of Hypoxic and Hyperoxic Preconditioning on Endothelial Function in a Model of Myocardial Ischemia-Reperfusion Injury with Cardiopulmonary Bypass (Experimental Study).

The aim of the experiment was to evaluate the effect of preconditioning based on changes in inspiratory oxygen fraction on endothelial function in the model of ischemia-reperfusion injury of the myocardium in the condition of cardiopulmonary bypass. The prospective randomized study included 32 rabbits divided into four groups: hypoxic preconditioning, hyperoxic preconditioning, hypoxic-hyperoxic preconditioning, and control group. All animals were anesthetized and mechanically ventilated.

Myocardial Protection against Ischemic and Reperfusion Injuries (Experimental Study).

The effects of hypoxic, hyperoxic, and hypoxic-hyperoxic preconditioning were examined in the prospective study on narcotized and artificially ventilated rabbits. Under artificial circulation, acute myocardial ischemia was modeled by ligation of anterior descending coronary artery, which was followed by reperfusion. The degree of ventricular arrhythmias was assessed, and the ischemic area was evaluated in percent of the area at risk.

[The phenomenon of ischaemic postconditioning of the heart. Analysis of clinical data].

Data concerning the effectiveness of ischaemic postconditioning (IPost) in treatment of acute ST-segment elevation myocardial infarction (STEMI) are controversial. The authors of the majority of studies have reported an anti-apoptotic and infarct reducing effect of IPost. There is evidence that IPost reduces the microvascular obstruction zone, increases coronary flow reserve, and improves the pumping functions of the heart.

[Ischaemic postconditioning of the heart. Analysis of experimental findings].

The data of publications regarding the influence of experimental atherosclerosis on the infarct-limiting effect of ischaemic postconditioning (IPost) are controversial. The presented information is suggestive that ageing removes or attenuates the infarct-limiting effect of postconditioning but does not influence the antiarrhythmic effect of IPost. The majority of experimental data report that streptozotocin-induced diabetes removes the infarct-limiting effect of IPost.