Computed Tomography derived Fractional Flow Reserve (FFRCT) is a non-invasive functional test providing anatomical and functional evaluation of the overall coronary tree. These unique features could help to tackle difficult decisions in patients presenting anomalous coronary connection (ANOCOR).

We aimed to evaluate the hemodynamic impact of different types of ANOCOR using FFRCT in a large cohort of patients.

Adult patients with ANOCOR detected during coronary angiogram or computed tomography (CT) were included in the multi-centric ANOCOR registry. Hundred and six patients were evaluated between 2009 and 2012 with a coronary CT at the time of inclusion. Patients with coronary artery connection from the pulmonary arterial trunk were excluded from the analysis.

FFRCT values could be calculated in 60 patients. Mean age of patients was 58±14 years, 47 (78%) were male. Preaortic, retroaortic, subpulmonar and prepulmonar courses were observed respectively in 34 (53%), 16 (27%), 6 (8%) and 4 (8%) patients. Mean FFR values were 0.82±0.11 in preaortic, 0.85±0.08 in retroaortic, 0.81±0.16 in subpulmonar, and 0.83±0.12 in prepulmonar courses. No statistical difference was observed between courses (P>0.05). The ANOCOR involved the left main/left anterior descending (LM/LAD) in 10 patients (17%), the left circumflex (LCx) in 11 patients (18%) and the right coronary artery (RCA) in 39 patients (65%). In ANOCOR vessels, mean FFR values in LM/LAD, LCx and RCA were respectively 0.81±0.13, 0.81±0.12 and 0.83±0.11 (P>0.5 for all). FFRCT analysis showed mean FFR value downstream the ANOCOR was 0.90±0.09. In the distal part of ANOCOR vessels mean FFR value was significantly lower compared to non ANOCOR vessel respectively 0.83±0.10 versus 0.87±0.09 (P=0.0003) (Fig. 1).

The hemodynamic impact of different forms of ANOCOR measured with FFRCT showed majority of values above 0.80 in ANOCOR and non ANOCOR vessels.