Minimally invasive off-pump coronary artery bypass grafting is associated with reduced postoperative intra-aortic balloon pump use.

BACKGROUND

Minimally invasive cardiac surgery-coronary artery bypass grafting (MICS-CABG) is increasingly adopted; however, its association with postoperative intra-aortic balloon pump (IABP) use-a marker of refractory low cardiac output-has not been well characterized in large patient cohorts. This study aimed to evaluate whether MICS-CABG was independently associated with reduced postoperative IABP use compared with conventional sternotomy CABG.

METHODS

We retrospectively analyzed 2,084 patients who underwent CABG between 2017 and 2024 at a single high-volume center (sternotomy: n=1,458; MICS-CABG: n=626). All procedures were primarily off-pump. The primary outcome was postoperative IABP use. Multivariable logistic regression was used to identify independent predictors, and propensity score matching (PSM) was performed to control for baseline differences. Mediation analysis assessed whether operative time or transfusion volume explained the observed association.

RESULTS

Postoperative IABP use was significantly lower after MICS-CABG than after sternotomy, both in the overall cohort (1.8% vs. 4.3%, P=0.004) and in the PSM cohort (1.5% vs. 3.9%, P=0.008). After full multivariable adjustment, MICS-CABG remained independently associated with reduced odds of postoperative IABP use [odds ratio (OR) 0.45, 95% confidence interval (CI) 0.23-0.90; P=0.02]. Mediation analysis indicated that operative time accounted for 15.1% of this association (P=0.02), whereas transfusion volume showed no significant mediating effect. A learning curve analysis suggested that surgical proficiency in MICS-CABG was attained after approximately 225 cases.

CONCLUSIONS

In a center using a standardized rescue-IABP protocol, MICS-CABG was associated with significantly lower postoperative IABP utilization compared with conventional sternotomy CABG. This association was partly mediated by shorter operative time, suggesting that procedural efficiency may contribute to improved perioperative hemodynamic stability. However, these findings should be interpreted in the context of potential residual confounding, including differences in patient selection, sex distribution, and revascularization complexity reflected by the number of grafts.