Physiological impact of coronary artery bypass surgery on chronic total occlusion: a functional evaluation using coronary flow reserve.

AIMS: This study evaluated the physiological impact of CABG for left anterior descending (LAD) artery chronic total occlusion (CTO) using postoperative coronary flow reserve (CFR).

METHODS

We retrospectively analyzed 1,149 patients undergoing isolated CABG, comparing LAD-CTO (n = 164) and non-CTO (n = 985) groups. Postoperative CFR was measured in 685 patients. The CTO group was stratified by preoperative Rentrop collateral classification.

RESULTS

In the entire cohort (n = 1,149), early mortality (3.7% vs. 1.7%, p = 0.1018) and LAD graft patency (97.8% vs. 98.6%, p = 0.4595) were comparable between groups. In the CFR cohort (n = 685), the CTO group showed lower CFR values than the non-CTO group (2.76 ± 0.90 vs. 3.04 ± 0.88, p = 0.0012). However, mean CFR exceeded 2.0 across all CTO subgroups, regardless of collateral status (Poor: 2.66 ± 0.7; Moderate: 2.76 ±0.94; Good: 2.78 ± 1.00; p = 0.763).

CONCLUSIONS

CABG achieves reliable physiological improvement (CFR > 2.0) and favorable outcomes for LAD-CTO revascularization, independent of preoperative Rentrop collateral grade.