Outcomes from Quantitative Flow Ratio-Guided Complete Revascularization and Angiography-Guided Percutaneous Coronary Intervention in Patients with ST-Segment Elevation Myocardial Infarction.

BACKGROUND Quantitative flow ratio (QFR) is a non-invasive angiographic tool that provides functional assessment of coronary stenosis without the need for pressure wires or hyperemia. This prospective study aimed to evaluate the procedural and inpatient treatment outcomes of QFR-guided percutaneous coronary intervention (PCI) compared with that of angiography-guided PCI in patients with ST-elevation myocardial infarction (STEMI) undergoing staged revascularization of non-culprit lesions. MATERIAL AND METHODS This randomized prospective single-center study was conducted at the Hospital of the Lithuanian University of Health Sciences Kaunas Clinics (July 2020-June 2021). After successful culprit-lesion PCI for STEMI, 124 participants with residual angiographically significant non-culprit stenosis (50-75%) were randomized to QFR-guided (n=62) or angiography-guided PCI (n=62). Procedural characteristics, fluoroscopy time, contrast usage, stent number/length, and inpatient treatment outcomes were compared between groups using SPSS 28.0 software. RESULTS Compared with PCI guided by visual estimation alone, the QFR-guided PCI group showed significant reductions in fluoroscopy time (median 6.2 vs 8.0 min, P=0.009), contrast volume (median 100 vs 120 mL, P=0.038), number of stents implanted (median 1.5 vs 2.0, P=0.002), and stent length (median 28 vs 45 mm, P<0.001). No significant differences were found between the groups in terms of periprocedural complications or length of inpatient stay. CONCLUSIONS QFR-guided PCI of the non-culprit lesion resulted in shorter fluoroscopy time, lower contrast volume, and a smaller number and average length of implanted stents. These findings highlight the potential of QFR to enhance procedural efficiency and reduce unnecessary stenting in clinical practice without compromising patient outcomes.