A quantitative flow ratio (QFR)-guided strategy did not provide the same prognostic benefits as a fractional flow reserve (FFR)-guided strategy for patients with intermediate coronary stenosis, based on findings from the FAVOR III Europe trial presented at TCT 2024 and simultaneously published in The Lancet.

Researchers enrolled 2,000 patients from 34 centers in 11 European countries with either chronic coronary syndrome or stabilized acute coronary syndrome and with at least one intermediate non-culprit lesion (40–90% diameter stenosis by visual estimate). Participants were randomized 1:1 to either a QFR-guided strategy or FFR-guided strategy, using a concealed web-based system and stratified by diabetes and presence of a left anterior descending coronary artery study lesion. The primary endpoint was a composite of death, myocardial infarction (MI), and unplanned revascularization at 12 months.

At 12 months, a primary endpoint event occurred in 67 patients in the QFR group (6.7%) compared with 41 patients in the FFR group (4.2%). According to the researchers, the event proportion difference was 2.5% and the upper limit of the 90% confidence interval exceeded the prespecified noninferiority margin of 3.4%. A total of 18 patients in each group (1.8%) experienced an adverse procedural event, with the most frequent being procedure-related MI. One patient in the QFR group died in relation to the index procedure.

"The results of the FAVOR III Europe trial do not support the use of QFR if FFR is available to guide revascularization decisions in patients with intermediate coronary stenosis," write Birgitte Krogsgaard Andersen, MD, et al. "This finding could have implications for current clinical guidelines recommending QFR for this purpose."