Comparison of a coronary bypass surgery using a combination of both on-pump beating heart and cardioplegic arrest with conventional coronary bypass surgery using cardioplegic arrest on-pump.

Objective: Antegrade cardioplegia may cause maldistribution in patients with multivessel coronary artery disease. Surgically bypassing large epicardial vessels before the cross-clamp and then administering cardioplegia from both the aortic root and the anastomosed grafts significantly prevent maldistribution and provide better cardiac protection.

Methods: This study included 80 patients, all older than 70 years with an ejection fraction between 25 and 35%. Patients were equally divided into two groups. Distal anastomoses to some of large epicardial coronary arteries were performed before the cross-clamp was placed. Grafted veins were attached to multi-perfusion set ports. Then, cross-clamping was performed, and the multi-perfusion set was disconnected from the aortic cannula and attached to the cardioplegia route. Antegrade cardioplegia was administered to both the aortic root and saphenous vein grafts. After all distal anastomoses were completed, the cross-clamp was removed, and the multi-perfusion set was connected to the aortic cannula again. Conventional coronary bypass techniques were used in group 2 patients.

Results: Inotropic agents were administered in 12 patients in group 1 and 29 patients in group 2 (p < 0.001). The average troponin I value in coronary sinus blood was 1.05 ± 0.8 ng/mL in group 1 and 3.12 ± 0.7 ng/mL in group 2 (p < 0.001). The average lactate value in coronary sinus blood was 1.15 ± 0.55 mmol/L in group 1 and 3.7 ± 2.4 mmol/L in group 2 (p < 0.001). Six patients died in the early postoperative period in group 2 (p = 0.028).

Conclusion: The current technique considerably reduces cross-clamping time and allows better distribution of the cardioplegic solution, preserving myocardium. Reduced coronary sinus lactate and troponin I levels also indicate better myocardial protection.