The prognostic value of combined intracoronary pressure and blood flow velocity measurements after deferral of percutaneous coronary intervention

Objectives : We evaluated deferral of PCI of intermediate coronary lesions (IL) using fractional (FFR) and coronary flow reserve (CFR) hyperemic stenosis resistance index (HSR) in patients with a negative or nondiagnostic and noninvasive stress tests. Background : Outcome after deferral of PCI of IL with discordant results between FFR and CFR is unknown. Methods : PCI was deferred in 186 IL (mean diameter stenosis: 52%). Patients were divided according to the results of FFR and CFR in group A; FFR ≥ 0.75 and CFR ≥ 2.0 (n = 129), group B; FFR ≥ 0.75 and CFR 2.0 (n = 28), group C; FFR 0.75 and CFR ≥ 2.0 (n = 23) and group D; FFR 0.75 and CFR 2.0 (n = 6). Patients were followed for one year to document major adverse cardiac events (MACE). Results : Nineteen MACEs (0 deaths, 4 myocardial infarctions, 1 CABG, and 14 PCIs) occurred during a follow up of 323 ± 88 days. MACE rate was lowest (4.7%) when FFR, CFR, and HSR were normal. A higher MACE rate was observed when concordant abnormal (group D) or discordant results between FFR and CFR (group B and C) were compared to concordant normal values (group A, 33.3% vs. 19.7% vs. 5.4%, P = 0.008). Multivariate regression analysis showed a higher predictive power for HSR than for FFR and CFR. Conclusions : Abnormal FFR or abnormal CFR was documented in 31% of intermediate coronary lesions. Deferral of PCI in this group was associated with a high MACE rate, which underscores the rationale of combined pressure and flow measurements providing a stenosis resistance index that is better suited for clinical decision making in these lesions. © 2008 Wiley‐Liss, Inc.