Oxidative stress and platelet activation during on-pump and off-pump coronary artery bypass grafting in patients with double grafted vessels

Abstract

This study aimed to evaluate the oxidative stress status and two markers of platelet activation and reactivity in off-pump versus on-pump coronary artery bypass surgery. Study groups of 65 patients with double coronary artery bypass grafting were divided into cardiopulmonary bypass (CPB) and off-pump coronary artery bypass groups. In serial blood samples, lipid hydroperoxides (LOOH), serum paraoxonase (PON1), advanced oxidation protein products (AOPP), total sulfhydryl groups (tSHG) and red blood cell distribution width (RDW) to platelet (Plt) ratio (RPR) and mean platelet volume (MPV) to platelet (Plt) ratio (MPR) index were determined to compare the extent of oxidative stress and platelet activation. The MPR and RPR rose significantly in the post-operative period (P < 0.001) in both groups. The increase was higher in the CPB group, but this difference reached borderline significance at 48 h post-operatively. The AOPP/tSHG index increased 6 h after surgery, preceded by a significant fall of the PON1/LOOH ratio, more evident in the CPB group. Multiple linear regression analysis showed explicit connection between these markers and surgery-related clinical conditions. Receiver operating characteristic analysis enabled estimation of the clinical accuracy of oxidative plus platelet-related indices in prediction of surgery caused complications (area under the curve for the model consisted of oxidative stress parameters and platelet activation indices was above 0.9, P < 0.001). Results showed higher oxidative stress and undesirable platelet activation in the CPB group. Oxidative status markers and platelet activity indices showed good clinical accuracy to predict the development of possible surgical complications.

Keywords

• Oxidative stress
• platelet activation
• off-pump coronary artery bypass
• cardiopulmonary bypass
• beating heart