Long-term outcomes were comparable with fractional flow reserve (FFR)-guided and IVUS-guided treatment in patients with intermediate coronary stenosis, according to an extended follow-up of the FLAVOUR trial published in JACC.

During the FLAVOUR trial, across 18 sites in South Korea and China, 1,682 patients with de novo intermediate coronary stenosis (40-70%) and target vessel diameters ≥2.5 mm were randomized to either FFR-guided (n=838) or IVUS-guided (n=844) treatment. Their mean age was 65 years and 29% were women, and two-thirds had stable angina and a third had diabetes.

Over a median follow-up of 6.3 years, 179 (23%) FFR-treated and 160 (21%) IVUS-treated patients experienced the primary composite endpoint of all-cause death, myocardial infarction and any revascularization within two years following the index procedure (hazard rate [HR], 1.15; p=0.208).

Notably, the rates of revascularization were higher in the FFR than the IVUS group (15% vs. 12%; HR, 1.32; p=0.049), particularly for target vessel revascularization (10% vs. 6%; HR, 1.67; p=0.007) and driven primarily by late (two to seven years) revascularization in vessels in which PCI was initially deferred.

However, the overall rate of target vessel PCI, both index procedure and revascularization follow-up, was significantly lower in the FFR group than the IVUS group (39% vs. 61%; p<0.001).

"FFR may be the preferred option in cases in which the purpose is to avoid unnecessary PCI without compromising long-term hard outcomes," write study authors Seokhun Yang, MD, et al. "Conversely, if a more proactive revascularization strategy is desired to potentially reduce future coronary events, IVUS can serve as an effective upfront tool for guiding treatment decisions and optimizing procedural results."

"So what's better?" Allen Jeremias, MD, FACC; Rick H.J.A. Volleberg, MD; and Ziad A. Ali, MD, DPhil, ask in an accompanying editorial comment. "In the end, FLAVOUR does not crown a winner... Knowing which flavor to choose may depend less on the patient and more on the operator – and whether we are treating the present or protecting the future."