Selective FFR_CT testing in suspected stable angina in clinical practice - initial experiences

Coronary CT angiography (CTA) derived fractional flow reserve (FFR_CT) is recommended for physiological assessment in intermediate coronary stenosis for guiding referral to invasive coronary angiography (ICA). In this study, we report real-world data on the feasibility of implementing a CTA/FFR_CT test algorithm as a gatekeeper to ICA at referral hospitals. Retrospective all-comer study of patients with new onset stable symptoms and suspected coronary stenosis (30-89%) by CTA. Evaluation of CTA datasets, interpretation of FFR_CT analysis, and decisions on downstream testing were performed by skilled CT-cardiologists. CTA was performed in 3974 patients, of whom 381 (10%) were referred directly to ICA, whereas 463 (12%) to non-invasive functional testing: FFR_CT 375 (81%) and perfusion imaging 88 (19%). FFR_CT analysis was rejected in 8 (2%) due to inadequate CTA image quality. Number of patients deferred from ICA after FFR_CT was 267 (71%), while 100 (27%) were referred to ICA. Obstructive coronary artery disease (CAD) was confirmed in 62 (62%) patients and revascularization performed in 53 (53%). Revascularization rates, n (%), were higher in patients undergoing FFR_CT-guided versus CTA-guided referral to ICA: 30-69% stenosis, 28 (44%) versus 8 (21%); 70-89% stenosis, 39 (69%) versus 25 (46%), respectively, both p < 0.05. Implementation of FFR_CT at referral hospitals was feasible, reduced the number of invasive procedures, and increased the revascularization rate.