Lesion length-dependent effects of quantitative flow ratio-guided percutaneous coronary intervention

The FAVOR III China trial previously revealed that quantitative flow ratio (QFR)–guided percutaneous coronary intervention (PCI) achieved superior outcomes compared with angiography guidance. This predefined subgroup analysis was conducted to examine whether coronary lesion length modifying the clinical effect of QFR based revascularization strategy.

Overall, 3,825 patients were randomly assigned to either QFR-guided PCI (PCI performed only when QFR ≤ 0.80) or angiography-guided PCI. Lesions were categorized as long (≥ 20 mm) or short (< 20 mm), based on measurements from an independent imaging core laboratory. The primary study endpoint consisted of the composite of major adverse cardiac events (MACE), including myocardial infarction, ischemia-associated revascularization, and all-cause mortality over three years of follow-up.

A total of 1,877 patients were classified into the long-lesion group (931 QFR-guided and 946 angiography-guided), and 1,925 into the short-lesion group (974 QFR-guided, 951 angiography-guided). After three years, patients with longer lesions had a greater incidence of MACE relative to those with shorter lesions (15.5% vs. 9.8%; P < 0.0001). Relative to angiography, QFR guidance led to a reduction in PCI procedures in both strata 14.8% in the short-lesion group and 2.4% in the long-lesion group. Relative risk reduction in MACE with QFR guidance was consistent regardless of lesion length: 7.1% versus 12.6% (HR = 0.55; 95% CI: 0.41–0.74) in the short-lesion group and 13.9% versus 17.0% (HR = 0.79; 95% CI: 0.63–1.00) in the long-lesion group (P_interaction = 0.06).

QFR-guided PCI was linked to fewer MACE relative to PCI guided by angiography after three years. The relative benefit was most pronounced in patients with shorter lesions.