Value of fractional flow reserve in the management of patients with moderate coronary stenosis.

INTRODUCTION: A considerable number of patients present a single intermediate lesion (>40% and <70%) in one coronary artery on coronary angiography, with no clear evidence that the lesion is responsible for the patient's symptoms. Fractional flow reserve is a method of evaluating the functional importance of stenosis, a value of <0.75 indicating hemodynamically significant lesions. The aim of this study is to determine the safety of non-revascularization of an angiographically moderate and hemodynamically non-significant lesion. METHODS: Fractional flow reserve (FFR) was evaluated in 87 patients over a period of 34 months. Retrospective analysis and follow-up were conducted of patients referred for coronary angiography, without acute coronary syndrome, who presented an angiographically moderate lesion of a single epicardial coronary artery with an FFR of 0.75, and in whom intervention was deferred. RESULTS: We found 21 patients with a mean age of 66 years, 66.7% male. All patients presented vascular risk factors, 14 with prior cardiovascular events. Before coronary angiography 7 patients were asymptomatic, 7 had atypical symptoms and 7 presented CCS class 2 angina. Among these patients, 16 performed a non-invasive stress test, which was positive in 11 patients and inconclusive or doubtful in the others. Angiographically most of the lesions were located in the left anterior descending artery (12 patients). In the 19 +/- 12-month follow-up, 16 patients were asymptomatic and the others maintained the same symptoms. There was no change in the amount of antianginal drugs prescribed. No cardiac events occurred. CONCLUSION: FFR is a useful tool when clinical symptoms and non-invasive tests are inconclusive in the presence of moderate stenosis in a coronary artery. In our group of patients, the decision to defer intervention based on an FFR of 0.75 was found to be safe and associated with absence of clinical events.