A new study suggests that fractional flow reserve (FFR) and intravascular ultrasound (IVUS) produce similar long-term patient outcomes in people with intermediate coronary stenosis. The multinational trial, which focused on the two strategies for guiding percutaneous coronary intervention (PCI), reports that the composite primary endpoint of all-cause death, myocardial infarction or any revascularization occurred in 22% of patients, with no statistically significant difference between groups. Patients treated with FFR guidance did, however, undergo fewer overall PCI procedures, though they showed higher rates of late revascularization after the initial intervention was deferred. “The primary outcome of death, MI, and any revascularization after the index procedure occurred in 339 patients (22.0%),” said the paper’s authors, led by Seokhun Yang, MD, from Seoul National University Hospital, in the Republic of Korea. “[There was] no statistically significant differences between the FFR-guided and IVUS-guided groups (179 [23.1%] vs 160 [20.9%], respectively; Hazard Ratio [HR]: 1.15; 95% confidence interval [CI:] 0.93-1.42; P = 0.208).” FLAVOUR follow up The investigation, which was published Monday online and in the Aug 26 issue of the Journal of the American College of Cardiology, was an extended follow-up of the FLAVOUR trial, and tracked 1,682 patients over a median of 6.3 years across 18 sites in Korea and China. Further findings revealed FFR guidance’s link to more revascularizations beyond two years, where the total burden of PCI procedures remained lower compared with IVUS. By 7 years, the overall rate of target vessel PCI was 38.8% in the FFR group compared with 60.5% in the IVUS group. More significantly, both strategies produced comparable rates of hard outcomes such as death and heart attack. “Although FFR-guided treatment was associated with a higher rate of late target vessel revascularization after the index procedure, the cumulative target vessel PCI rate, including both the initial procedure and subsequent revascularizations during follow-up, remained significantly lower in the FFR-guided group, without compromising long-term hard outcomes,” the research team wrote. The findings suggest that both approaches are safe and effective over the long term, with FFR offering the advantage of reducing unnecessary interventions, while IVUS may provide a more proactive strategy for preventing late revascularizations. Improving outcomes Commenting on the findings, Allen Jeremias, MD, Rick H.J.A. Volleberg, MD, and Ziad A. Ali, MD, from the St Francis Hospital & Heart Center in Roslyn, New York, argued that FFR and IVUS each improve outcomes over angiography. However, they added that they achieved their benefits through different mechanisms with FFR limiting unnecessary stenting and IVUS helping to identify and treat high-risk plaques that might otherwise progress. “If the goal is to reduce procedural complexity and avoid unnecessary PCI, FFR seems to be the optimal tool,” noted the commentators. “However, if the aim is to reduce long-term events driven by plaque instability, IVUS may hold an advantage.” The commentators emphasized that the study should not be seen as crowning a winner. Instead, both tools may be best viewed as complementary, with potential future strategies combining anatomical and physiological insights. “In the end, FLAVOUR does not crown a winner; it exposes duality. FFR and IVUS improve outcomes, but they do so through different mechanisms: one by reducing stent burden, the other by reducing plaque burden and enabling precision PCI,” the editorialists concluded. Sources: Yang S, Hu X, Zhang J, et al. Long-Term Outcomes After Fractional Flow Reserve vs Intravascular Ultrasound to Guide PCI: The FLAVOUR Trial Extended Follow-Up. J Am Coll Cardiol. 2025;86:593–606. Jeremias A, Volleberg RHJA, Ali ZA. FLAVOUR: Just a Difference in Taste? J Am Coll Cardiol. 2025;86:607–609. Image Credit: iushakovsky – stock.adobe.com