Value of fractional flow reserve in making decisions about bypass surgery for equivocal left main coronary artery disease

Objective-To investigate the value of coronary pressure derived fractional flow reserve (FFR) measurements in supporting decisions about medical or su rgical treatment in patients with angiographically equivocal left main coro nary artery stenosis. Design-A two centre prospective single cohort follow up study. Interventions-FFR of the left main coronary artery was determined in 54 con secutive patients with angiographically equivocal left main coronary artery disease. If FFR was greater than or equal to 0.75, medical treatment was c hosen; if FFR was < 0.75, surgical treatment was chosen. Main outcome measures-Freedom from death, myocardial infarction, or any cor onary revascularisation procedure. Results-In 24 patients (44%), FFR was greater than or equal to 0.75 and med ical treatment was chosen (medical group). In the remaining 30 patients (56 %), FFR was < 0.75 and bypass surgery was performed (surgical group). Mean (SD) follow up was 29 (15) months (range 12-65 months). Survival among pati ents at three years of follow up was 100% in the medical group and 97% in t he surgical group. Event-free survival was 76% in the medical group and 83% in the surgical group. Conclusions-FFR supports decision making in equivocal left main coronary ar tery disease. If FFR is below 0.75, the decision for bypass surgery is supp orted. If FFR is above 0.75, a conservative approach is justified.