Comparison Of Perioperative Inflammatory Response And Myocardial Injury Between Conventional Coronary Artery Aypass Grafting And Off-Pump Coronary Artery Bypass Grafting

This study was to explore the difference of perioperative inflammatory response and degree of myocardial tissue injury by comparing on the perioperative inflammatory cytokines and indicators of myocardial injury release between conventional coronary artery bypass grafting (CCABG) and off-pump coronary artery bypass grafting(OPCAB). 1 Patients and methods 1.1 General informationForty-one patients with unstable angina were involved in the study, among them, 22 patients (mean-age 62.36±8.27 years old, preoperative ejection fraction(EF) 56.86±5.05% ) underwent off-pump coronary artery bypass grafting; 19 patients (mean-age 60.10 ± 7.46 years old, preoperative EF 53.32±6.67% )underwent conventional coronary artery bypass grafting. There were no significant differences of theage and the preoperative cardiac function between the twogroups.(P>0.05)1.2 Surgical methodsAll patients received a standardized anesthetic technique. In every instance, the operation was performed via a median sternotomy. The left internal mammary artery (LIMA) was dissociated with extrapleurae technique and a segment of saphenous vein (SV) was dissociated. The left anterior descending coronary artery (LAD) was anastomosed with LITA, and other coronary artery branches were anastomosed with SV.A standardized cardiopulmonary bypass(CPB) was performed in the CCABG group. All distal target arteries were anastomosed while the patients were perfused at a normal temperature or a light hypothermia. Proximal anastomosis was completed using tangential clamping after the heart was resuscitated.In the OPCAB group, All distal target arteries were anastomosed_under the circumstance that the movement of beating heart was dampen by stabilizer. Preximal anastomosis was completed using tangential clamping. LAD was anastomosed first and then SV. 1.4 Sample collection and analysisBlood samples were collected from the radial artery at the time of after induction of anesthesia, Smins, 2, 4, 12, and 24hs after reperfusion respectively in every patient. Theplasma TNF-a, IL-6, IL-8 and IL-10 in these samples were measured with radioimmunoassay method. Venous blood samples were collected before induction of anesthesia, 12h and 24h after operation to determine the levels of CK-MB and cTnl. The standard ECG was recorded preoperatively and on the 7th postoperative day.2 ResultsNo death or major complications as peri operative myocardial infarction and infection were found in the study.The preoperative levels of TNF-a, IL-6, IL-8, IL-10 and cTnI between two groups were similar. The levels of IL-6, IL-8 and cTnl increased significantly after surgery in both groups, and those of IL-8 and cTnl were higher in the CCABG group than in the OPCAB group (P<0.05). Postoperative levels of TNF-a and IL-10 have no significant rising in the OPCAB group (P>0.05), but increased significantly in CCABG group (P<0.05). The levels of cTnl at 12th hour after operation were highly positively correlated with the peak levels of TNF-a, IL-6 and IL-8 (P<0.05).3 ConclusionsCPB might be a major factor of inflammatory response after conventional coronary artery bypass grafting. Compared with CCABG, OPCAB is associated with reduced cytokine release and less myocardial injury. Postoperative myocardial injury were correlated with the peak level of TNF-α, IL-6andIL-8.