Early Noninvasive Evaluation of Coronary Flow Reserve after Angioplasty in the Left Anterior Descending Coronary Artery Identifies Patients at High Risk of Restenosis at Follow-Up

Background: Coronary restenosis is the most important clinical limitation after percutaneous coronary inter- vention (PCI), and coronary flow reserve (CFR) is reduced in the presence of significant coronary stenosis. This study evaluated whether detection of early reduction of Doppler echocardiographically derived CFR in the left anterior descending coronary artery can identify patients at high risk for developing restenosis after successful PCI. Methods: Doppler echocardiographically derived CFR was studied in 124 consecutive patients at 1-month and 6-month follow-up after PCI in the left anterior descending coronary artery, together with coronary angiography. Results: Restenosis was detected in 39 angiographic examinations (group A) and no coronary restenosis in the remaining 85 (group B) at 6 months. At 1 month, CFR was reduced in group A compared with group B (P < .0001), and a significant reduction of CFR in group A (P < .0001) but not in group B (P = .89) was detected at 6 months. CFR # 2.5 at 1 month was 67% sensitive and 87% specific for predicting significant restenosis, with positive and negative predictive values of 67% and 87%, respectively. Conclusions: CFR # 2.5 detected 1 month after PCI in the left anterior descending coronary artery has the potential to identify patients at higher risk for developing coronary restenosis and indicates the need for close clinical follow-up