Preliminary outcomes of quantitative flow ratio-guided coronary bypass grafting in primary valve surgery: A propensity score weighted analysisCentral MessagePerspective

Objectives: The guidelines recommend fractional flow reserve-guided coronary artery bypass grafting (CABG) during primary valve surgery without evidence. Quantitative flow ratio (QFR) is a novel coronary angiography (CAG)-based fractional flow reserve measurement. We aimed to compare the early clinical outcomes between QFR-guided and CAG-guided CABG in these patients. Methods: This observational study screened all 2081 patients admitted to our institution for elective primary mitral and/or aortic valve surgery from January 2017 to September 2020. Of them, all 188 patients with comorbid coronary artery lesions (visual estimated stenosis ≥50%) were included. Sixty-nine patients with QFR analysis received bypasses only for lesions with QFR ≤0.80 (QFR-guided group). The remaining 119 patients without QFR analysis received bypasses for all stenosis ≥50% (CAG-guided group). Propensity overlap weighting was used to neutralize the intergroup imbalance. The primary end point was major adverse cardiovascular events. Results: After propensity score weighting, the baseline characteristics were comparable. Concomitant coronary artery bypass grafting was performed 58.1% versus 100% in the QFR-guided and CAG-guided groups, respectively. The mean number of grafts was significantly lower in QFR-guided group than in the CAG-guided group (0.9 ± 0.7 vs 1.6 ± 0.5 [P