Myocardial ischemia serum markers in coronary artery bypass grafting by on-pump and off-pump techniques

ABSTRACT

Coronary Artery Bypass Grafting [CABG] is usually performed with Cardio Pulmonary Bypass [CPB]. However CPB has been associated with several adverse effects. Recently off-pump CABG technique is offered as an alternative to the standard on-pump technique. The purpose of this study was to evaluate the safety of the technique by estimating and comparing serum markers of myocardial ischemia; CK, CK-MB, LDH, AST, Cardiac Troponin 1 and some peri and postoperative complications after two types of surgical procedures. Seventy-three patients [58 males and 15 females] with angiographically defined CAD admitted to the hospital for CABG were selected. The off-pump technique was performed in 38 patients with mean age of 60 +/- 10.5 years. In 35 other patients with mean age of 55 +/- 10.4 years, the on-pump technique was applied. CK, CK-MB, LDH and AST activities and Cardiac Troponin 1 concentration were measured pre and postoperatively into first 24 hours. Characteristics of the patiaents and some pre and postoperative data regarding incidence of complications were also recorded. The activities of cardiac enzymes; CK, CK-MB, LDH and AST after on-pump CABG technique were higher than those of off-pump technique [P<0.05 in all cases]. The levels of Troponin I were significantly higher after on-pump CABG throughout the entire measurement period [P<0.01]. In other groups of the patients no preoperative myocardial infarction was observed. In the off-pump technique procedure time was shorter and transfusion of blood and blood products was less than those of on- pump technique, but no differences were noticed among the other recorded data. Significantly lower release of the enzymes and Troponin 1 during operation by off-pump technique suggests that the technique causes less myocardial injury. On the basis of little change in the activities of cardiac enzymes and Troponin 1 and presented data including a marked decrease in blood transfusion and shorter procedural time it is concluded that off-pump CABG is a safe and effective technique in selected patients with appropriate coronary lesions