Anomalous origin of the right coronary artery (ARCA) represents the most common form of abnormal coronary origin and may potentially increase the risk for sudden cardiac death. Morphological and functional evaluation of ARCA in adult patients referred for invasive coronary angiogram (ICA) is challenging. Quantitative flow ratio (QFR) is an available method able to virtually calculate fractional flow reserve using 3-dimensional quantitative coronary angiography (3D-QCA) based on ICA. We aimed to evaluate the feasibility of QFR analysis in patients with ARCA and its clinical impact.
Using the registry of proximal anomalous connections of coronary arteries (ANOCOR registry), a multicenter observational registry including 472 adult patients with ANOCOR between 2010 and 2013, we retrospectively performed QFR analysis from ICA and evaluated the rate of death, myocardial infarction, and unplanned revascularization at 5 years.
Among 128 patients with ARCA, 41 (32%) could have QFR analysis with median clinical follow-up of 8.3 years. The mean QFR value was 0.90 ± 0.10, and 3D-QCA analysis showed preserved lumen area despite the elliptical shape of the proximal part of the ARCA, which in the worst cases appeared on ICA as a significant narrowing. The event rate was 12.2% (n = 5), including 3 deaths (1 due to cancer, 1 due to stroke, and 1 cause unknown) and 2 unplanned revascularizations at 5 years. No myocardial infarctions were reported.
When QFR analysis of ARCA is feasible, non-significant QFR values are associated with good clinical outcome at 5 years.