Comparing the Clinical Outcomes of Fractional Flow Reserve and Intravascular Imaging in Guiding Percutaneous Coronary Intervention: A Systematic Review and Meta-analysis.

BACKGROUND

Fractional flow reserve (FFR) and intravascular imaging (IVI) are both used to guide management of intermediate coronary stenoses, but comparative outcome data remain limited.

METHODS

We systematically searched MEDLINE/PubMed and the Cochrane Central Register of Controlled Trials from inception through September 1, 2025, for randomized controlled trials and comparative observational studies directly comparing physiology-guided versus intravascular imaging-guided strategies for angiographically intermediate coronary stenoses. Outcomes included major adverse cardiovascular events (MACE), all-cause mortality, cardiac mortality, myocardial infarction (MI), target-vessel revascularization (TVR), and PCI rate. Risk ratios (RRs) with 95% confidence intervals (CIs) were pooled using random-effects models. Risk of bias was assessed with RoB 2 for randomized trials and ROBINS-I for observational studies. A sensitivity analysis excluded FLAVOUR II because it used angiography-derived rather than pressure-wire FFR.

RESULTS

Six comparative studies including 5,047 participants were included: four randomized trials and two observational studies. No statistically significant differences were detected in all-cause mortality (RR 0.87, 95% CI 0.53-1.42; p=0.58), cardiac mortality (RR 1.11, 95% CI 0.63-1.96; p=0.72), MACE (RR 1.09, 95% CI 0.88-1.35; p=0.42), nonfatal MI (RR 1.45, 95% CI 0.80-2.64; p=0.22), or TVR (RR 1.27, 95% CI 0.85-1.90; p=0.24). Physiology guidance was associated with lower PCI utilization (RR 0.60, 95% CI 0.48-0.75; p<0.001), with substantial heterogeneity (I²=93.6%). Exclusion of FLAVOUR II did not materially alter the findings, including PCI utilization (RR 0.55, 95% CI 0.45-0.67; I²=76.7%).

CONCLUSIONS

Among patients with intermediate coronary stenoses, FFR- and IVI-guided strategies were associated with similar clinical outcomes, while FFR guidance reduced PCI utilization.