Prooxidant-antioxidant balance and cardiac function in patients with cardiovascular disease following cardiac surgery.

Cardiopulmonary bypass (CPB) is used during on-pump coronary artery bypass grafting (CABG) and heart valvular replacement surgery, and is associated with the induction of oxidative stress. The aim of the study was to assess the association between indices of cardiac function and prooxidant-antioxidant balance (PAB) values in patients undergoing valve replacement surgery and on-or off-pump CABG. Data were obtained from 44, 33, and 41 patients undergoing off-pump CABG, on-pump CABG, and valve replacement surgery, respectively. The PAB values were measured 24 h before and after the operative procedure, and at the time of discharge. Echocardiography was performed before surgery and before discharge. The changes in E/E', end-diastolic volume, end-systolic volume, left ventricular diastolic and systolic diameter were significantly related to baseline PAB values. In the valve replacement group, neither baseline nor changes in PAB values were associated with echocardiographic measurements. Also, neither off-pump nor on-pump CABG were significantly different in inducing oxidative stress (p = 0.596). When PAB values were measured in CABG patients, there was a significant difference in values between the three time points (p = 0.013). In the valve replacement group, PAB values were not significantly different between the preoperative and postoperative samples. The inverse association between the level of oxidative stress and cardiac function measurement may indicate that high levels of oxidative stress may be a predictor of the deterioration of cardiac function in CABG patients. However, in valvular heart disease patients the serum PAB value was not associated with changes in cardiac function. Levels of oxidative stress, as assessed by the PAB assay, were not significantly different for patients undergoing surgery with or without CPB.