On-Pump Versus Off-Pump Coronary Artery Bypass Grafting: A Comparison of Outcomes in Patients Receiving LIMA-LAD and Sequential No-Touch Saphenous Vein Graft Anastomoses.

AIM: Coronary artery bypass grafting (CABG), whether conducted using on-pump or off-pump strategies, exhibits distinct perioperative risk profiles. When combined with left internal mammary artery (LIMA) to left anterior descending artery (LAD) grafting and sequential no-touch saphenous vein graft (SVG) anastomosis, these differences gain clinical relevance. Therefore, this study aims to compare the clinical outcomes of on-pump CABG and off-pump CABG in patients who uniformly received the LIMA-LAD graft combined with sequential no-touch SVG anastomosis.

METHODS: This retrospective cohort study included 240 patients who received LIMA-LAD grafting combined with sequential no-touch SVG anastomosis between June 2019 and December 2023. Of the total patients, 61 received the procedure under cardiopulmonary bypass and were assigned to the on-pump group, while 179 underwent off-pump coronary artery bypass, categorized as the off-pump group. After propensity score matching (PSM; 1:1 ratio), 57 pairs were successfully matched and analyzed. The primary endpoint of the study included the incidence of major adverse cardiovascular and cerebrovascular events (MACCE), a composite of all-cause mortality, myocardial infarction, stroke, or target vessel revascularization, within one year after surgery. A key secondary endpoint was a graft patency rate assessed within one year after the procedure, including the LIMA-LAD graft and the sequential SVGs. Other secondary endpoints included: (1) postoperative recovery metrics, such as intensive care unit (ICU) stay duration, duration of mechanical ventilation, volume of thoracic drainage, and blood transfusion requirements; (2) hemodynamic parameters at 24 hours post-operation, including cardiac index (CI), pulmonary artery wedge pressure (PAWP), left ventricular stroke work index (LVSWI), stroke volume index (SVI), mean arterial pressure (MAP), and systemic vascular resistance index (SVRI); and (3) short-term postoperative complications (e.g., atrial fibrillation, acute kidney injury (AKI), sternal wound infection, and lower extremity venous territory infection).

RESULTS: There was no significant difference in the one-year incidence of MACCE between the off-pump and on-pump groups (p > 0.05). Similarly, no significant differences were found in the one-year patency rates of the LIMA-LAD graft or the sequential SVGs between the two groups (p > 0.05). Compared to the on-pump group, the off-pump group had shorter ICU stays, reduced duration of mechanical ventilation, lower thoracic drainage volumes, and decreased blood transfusion requirements (p < 0.001). Furthermore, no significant difference was observed in total hospitalization duration between the two groups (p > 0.05). Preoperatively, none of the hemodynamic parameters achieved statistical significance between the two groups (p > 0.05). At 24 hours postoperatively, both groups showed substantial within-group improvements (off-pump: all parameters; on-pump: CI, PAWP, LVSWI, SVRI; p < 0.05). However, between-group comparisons revealed better CI, PAWP, LVSWI, SVI and SVRI levels in the off-pump group (p < 0.05). Within 1 month postoperatively, the off-pump group experienced a lower incidence of atrial fibrillation (p < 0.05). Additionally, there were no significant differences in the rates of AKI, sternal wound infection, or leg wound infection between the two groups within 2 months postoperatively (p > 0.05).

CONCLUSIONS: Compared to on-pump CABG, off-pump CABG utilizing sequential no-touch SVG anastomosis offers advantages in terms of earlier recovery and superior hemodynamic performance without compromising graft patency or increasing the long-term risk of major adverse cardiovascular and cerebrovascular events.