Background

Patients with coronary artery disease and concomitant heart failure (left ventricular ejection fraction < 35%) requiring myocardial revascularization are at risk of poor long-term prognosis and higher mortality. The benefits of minimally invasive extracorporeal circulation (MiECC), particularly in end-stage coronary artery disease patients undergoing myocardial revascularization, have not been completely described.

Materials and methods

In this single-centre control study, 60 end-stage coronary artery disease patients undergoing isolated coronary artery bypass grafting (CABG) were included. Patients were divided into two groups of 30 patients each undergoing CABG using MiECC or conventional extracorporeal circulation (cECC).

Results

In the MiECC group, oxygen delivery index (DO_2i) was 305 mL/min/m² in relation to indexed oxygen extraction ratio (O₂ER_i) 21.5%, whereas in the cECC group DO_2i was 288 mL/min/m² in relation to O₂ER_i 25.6% (p = 0.037). Lactate levels > 3 mmol/L were reported in 7 MiECC patients vs 20 cECC patients (p = 0.038), with blood glucose peak. Mean nadir hemoglobin values during cardiopulmonary bypass (CPB) were 9.7 g/dL in the MiECC group vs 7.8 g/dL in the cECC group (p = 0.044). Cardiac index during CPB was 2.4 L/min/m² in both groups. Red blood cell units administered were 8 vs 21 units in the MiECC vs cECC group (p = 0.022). A glycemic peak was recorded in 7 patients of the MiECC group and in 20 patients of the cECC group (p = 0.037).

Conclusion

In end-stage coronary artery disease, the MiECC technique was associated with a higher DO_2i compared to cECC. MiECC patients showed a significant reduction in red blood cell unit administration and peak intraoperative lactate levels, which correlated with better postoperative outcome.