Assessment of Intermediate Coronary Stenosis in Koreans Using the Fractional Flow Reserve

Background and Objectives: Previous studies that used physiologic parameters have shown that coronary angiogra- phy is not always accurate in the evaluation of intermediate lesions. We sought to evaluate the outcomes of Korean patients for whom revascularization was deferred according to their fractional flow reserve (FFR). Subjects and Methods: FFR was measured in 107 intermediate lesions (visually estimated percent stenosis: 40-70%) in 102 con- secutive patients (68% males, mean age: 62±9 years). The one-year cardiac adverse outcomes (cardiac death, myo- cardial infarction or target vessel revascularization) of all the patients and the long-term outcomes of the patients for whom revascularization was deferred according to the FFR were evaluated. Results: The mean percent diameter stenosis was 57±11% and the FFR was 0.82±0.10. Only 25 lesions (23%) had a FFR <0.75. There was no sig- nificant difference in the 1-year cardiac event rates between the FFR ≥0.75 group and the FFR <0.75 group (10.4% vs. 13.0%, respectively, p=0.49). There was a tendency of a lower incidence of 1-year cardiac events in the medical treatment group than in the revascularizaton group (8.0% vs. 20.0%, respectively, p=0.10). In the 69 patients with FFR-guided deferral of revascularization, the long-term (mean follow-up duration: 41±11 months) cardiac event- free survival rate was 86%. Conclusion: The measurement of FFR seems to be a useful guide for decision making and it may reduce unnecessary intervention in Korean patients who suffer with intermediate stenosis. (Korean Circ J 2008;38:468-474)