Studying the effect of ischemic postconditioning and controlled aortic root reperfusion on myocardial protection in CABG surgery with cardiopulmonary bypass

Objective: Some degree of cardiac ischemia is seen in cardiac operation due to the decrease in coronary blood flow and re-perfusion injury. Myocadial infarction and decreased cardiac output are the main results of these injuries. In order to control the severity of these injuries, we will use a new type of conditioning strategy namely ischemic post conditioning in our study. Setting and conduct: Patients included in study are candidate for CABG, all will be undergoing cardiopulmonary. Then the aortic cross clamp will be applied and heart will be stopped. After completion of operation and just before releasing of cross clamp, coronary blood flow will be reestablished in three ways: controlled perfusion pressure, post conditioning and simultaneous technique. Inclusion criteria: Age 50-70; Left Ventricular EF more than 40 percent; Complete occlusion of LAD; No redo cardiac operation. Excluction criteria: Concomitant operation; Aortic clamp time more than 100 minute; Cardiopulmonary bypass time more than 130 minute Intervention: Patients are divided in 3 groups: in first group, coronary perfusion with controlled perfusion perssure is applied, in second group we use intermittent clamping and de-clamping (each for 1 minute in three times), and in third group, we use both methods together simultaneously.. Main outcome measures: cardiac enzymes, oxidative stress markers and ejection fraction will be measured after operation.

Vice chancellor for research, Tabriz University of Medical Scinces