Correlation of Computed Tomography Angiography and Fractional Flow Reserve Features with Symptoms in Patients with Right Coronary Artery Originating from the Left Coronary Sinus

Objective: This study aimed to explore the association between the anatomical and hemodynamic characteristics and the clinical symptoms in patients with the origin of the right coronary artery from the left coronary sinus (AORL) using coronary computed tomography angiography (CCTA) and CT fractional flow reserve (CT-FFR). Methods: A retrospective analysis was conducted on 151 patients with AORL detected by CCTA between January 2018 and December 2023 at our hospital. Patients were divided into the symptomatic (n=87) and asymptomatic (n=64) groups. CCTA images were used to compare anatomical differences of the RCA between both groups. CT-FFR values were measured and compared at 3 cm from the RCA ostium. Results: There were significant statistical differences between both groups regarding the RCA ostial morphology, origin angle, proximal lumen stenosis rate, length of the stenotic segment, and its relation to the pulmonary artery. The angle at the RCA ostium showed moderate correlation with clinical symptoms (r=0.566), whereas the ostial shape, proximal lumen stenosis rate, length of the stenotic segment, and relation to the pulmonary artery showed low correlation with symptoms. CT-FFR values were (0.94±0.02) and (0.97±0.01) for the symptomatic and asymptomatic groups, respectively, with a significant difference and moderate correlation with clinical symptoms (r=0.594). Conclusion: In patients with AORL, anatomical features, such as a slit-like RCA ostium, smaller origin angle, proximal lumen stenosis, long stenotic segment, and course between large arteries, are associated with clinical symptoms. Changes in CT-FFR are related to cardiovascular symptoms; however, further research is needed to determine measurement methods and critical values.