Abstract 13082: Higher Risk of Future Coronary Events at Deferred Coronary Lesions With a Gray Zone Fractional Flow Reserve in Patients With Intermediate Stenosis
Background: Deferral of revascularization of an intermediate coronary stenosis with fractional flow reserve (FFR) ≧0.75 was reported to be safe. However, the FFR value range between 0.75 and 0.80 has been recognized as a gray zone. We hypothesized that outcomes after deferral of revascularization between coronary lesions with gray zone FFR and those with non-ischemic FFR (>0.80) might be different. The aim of this study was to evaluate the clinical outcomes of patients with intermediate coronary stenosis with gray zone FFR compared to those with FFR >0.80.
Methods: We reviewed medical records of patients who underwent an FFR measurement at our hospital between January 2008 and December 2011. Long-term outcomes of 153 patients with angiographically intermediate coronary lesions deferred from revascularization on the basis of an FFR > 0.75 were obtained. We divided the patients into two groups. Gray zone group consisted of 57 patients with FFR values between 0.75 to 0.80. Non-ischemia group comprised 96 patients with FFR values above 0.80. The outcome of the gray zone group was compared with that of the non-ischemia group. The primary endpoint of this study was target vessel failure (TVF) defined as cardiac death, target vessel related myocardial infarction, and ischemia-driven target vessel revascularization.
Results: There were no differences in baseline clinical characteristics between two groups. Mean FFR value of deferred lesions was significantly lower in the gray zone group than the non-ischemia group (0.78 ± 0.02 vs. 0.88 ± 0.05). During a mean follow-up period of 2.8 ± 1.2 years, TVF occurred in 11 deferred lesions (7.2%). The incidence of TVF was significantly different between two groups: 14.0% in the gray zone group and 3.1% in the non-ischemia group (hazard ratio: 4.043, 95% confidence interval, 1.048 to 15.603; p = 0.043).
Conclusion: Not all deferred lesions based on FFR ≧ 0.75 were equally safe during the follow up period. Patients with deferred coronary lesions with the gray zone FFR had higher risk of TVF in the future than those with FFR >0.80.
- © 2013 by American Heart Association, Inc.