PRIME-FFR Evaluates Impact of Routine FFR on Management Decisions and Outcomes of ACS Patients

July 10, 2017—In Circulation: Cardiovascular Interventions, Eric Van Belle, MD, et al published findings from an evaluation of the impact of integrating fractional flow reserve (FFR) on management decisions and on clinical outcomes of patients with acute coronary syndromes (ACSs) undergoing coronary angiography, as compared with patients with stable coronary artery disease.

The investigators pooled the R3F (French FFR Registry) and POST-IT (Portuguese Study on the Evaluation of FFR-Guided Treatment of Coronary Disease), which shared a common design, to form the PRIME-FFR (Insights From the POST-IT and R3F Integrated Multicenter Registries—Implementation of FFR in Routine Practice) study. A prospectively defined management strategy was based on angiography before performing FFR. The investigators recorded the final decision after FFR and the 1-year clinical outcome.

As summarized in Circulation: Cardiovascular Interventions, there were 1,983 patients in whom FFR was prospectively used to guide treatment. From these, 533 sustained ACSs (excluding acute ST-segment elevation myocardial infarction). In ACS patients, FFR was performed in 1.4 lesions per patient, mostly in the left anterior descending artery (58%), with a mean percent stenosis of 58% ± 12% and a mean FFR of 0.82 ± 0.09. In patients with ACSs, reclassification by FFR was high and similar to those with non-ACSs (38% vs 39%; P = NS).

The pattern of reclassification was different, however, with less patients with ACSs reclassified from revascularization to medical treatment compared with those with non-ACSs (P = .01). In ACSs, the 1-year outcome of patients reclassified based on FFR (FFR against angiography) was as good as that of nonreclassified patients (FFR concordant with angiography), with no difference in major cardiovascular events (8% vs 11.6%; P = .2) or symptoms (92.3% vs 94.8% angina free; P = .25).

Moreover, FFR-based deferral to medical treatment was as safe in patients with ACSs as in patients with non-ACSs (major cardiovascular event, 8% vs 8.5%; P = .83; revascularization, 3.8% vs 5.9%; P = .24; and freedom from angina, 93.6% vs 90.2%; P = .35). These findings were confirmed in ACSs explored at the culprit lesion. In patients (6%) in whom the information derived from FFR was disregarded, a negative outcome was observed.

Routine integration of FFR into the decision-making process of ACS patients with obstructive coronary artery disease is associated with a high reclassification rate of treatment (38%). A management strategy guided by FFR, divergent from that suggested by angiography, including revascularization deferral, is safe in ACSs, concluded the investigators in Circulation: Cardiovascular Interventions.