Outcomes of Functionally Complete vs Incomplete Revascularization: Insights From the FAVOR III China Trial

Functional complete revascularization (FCR) after percutaneous coronary intervention (PCI) as determined by the residual functional SYNTAX score (rFSS) based on pressure wire fractional flow reserve assessment has been associated with an improved prognosis.

This study sought to determine the rates and clinical implications of FCR as assessed by the quantitative flow ratio (QFR), and to determine the outcomes of pre-PCI QFR guidance compared with standard angiography guidance in patients achieving and not achieving FCR after PCI.

In the randomized, sham-controlled, blinded, multicenter FAVOR (Comparison of Quantitative Flow Ratio Guided and Angiography Guided Percutaneous Intervention in Patients with Coronary Artery Disease) III China trial, QFR-guided PCI reduced the 1-year rate of major adverse cardiac events (MACE) compared with angiography-guided PCI. In the present prespecified substudy, the incidence of MACE was compared according to the presence of post-PCI FCR (rFSS = 0 based on core laboratory-assessed QFR) in the QFR-guided and angiography-guided groups.

Among 3,781 patients with available rFSS assessments, 3,221 (85.2%) achieved FCR, including 88.1% after QFR guidance and 82.2% after angiography guidance (P < 0.001). Patients with FCR had a markedly lower rate of 1-year MACE compared with those with functional incomplete revascularization (FIR) (rFSS ≥1) (5.1% vs 19.7%; P < 0.001). Prognostic models including the rFSS had higher discrimination and reclassification ability than those with the anatomic residual SYNTAX score. The relative risks for 1-year MACE with QFR-guided compared with the angiography-guided lesion selection were consistent in patients achieving FCR (4.1% vs 6.3%; HR: 0.65; 95% CI: 0.47-0.88) and in those with FIR (18.7% vs 20.4%; HR: 0.90; 95% CI: 0.61-1.32) (P_interaction = 0.19).

In this large-scale trial, achieving FCR after PCI was associated with markedly lower 1-year rates of MACE. Compared with standard angiography guidance, QFR-guided PCI lesion selection improved the likelihood of achieving FCR and improved 1-year clinical outcomes in patients with both FCR and FIR.