Coronary CT angiography derived FFR in patients with left main disease.

The presence of left main coronary artery disease (LMCAD) is associated with an unfavorable clinical outcome. The clinical utility of FFR testing for non-invasive physiological assessment in LMCAD remains largely unknown. In this single center observational study LMCAD patients were retrospectively identified between November 2015 and December 2017. We evaluated the relationship between LMCAD diameter stenosis and downstream FFR values, and the clinical consequences following FFR testing in patients with LMCAD. The composite endpoint (all-cause death, myocardial infarction, unplanned revascularization) was determined over a median follow-up of 1.1 years. LMCAD was registered in 432 of 3202 (13%) patients having coronary CTA. FFR was prescribed in 213 (49%), while 59 (14%) patients were referred directly to invasive angiography or myocardial perfusion imaging. FFR was performed in 195 (45%) patients. LM stenosis severity was inversely related to downstream FFR values. In patients with simple LMCAD with stenosis ≥ 50%, > 80% had FFR > 0.80 in non-diseased proximal and downstream segments (n = 7). No patients with simple LMCAD and FFR > 0.80 (n = 20) suffered an adverse clinical outcome. FFR testing in patients with LMCAD is feasible. LM stenosis severity is inversely related to FFR value. Patients with LMCAD and FFR > 0.80 have favorable clinical outcomes at short-term follow-up. Large-scale studies assessing the clinical utility and safety of deferring invasive catheterization following FFR testing in patients with LMCAD are warranted.