Could Right Coronary Artery-Aorta Angle be Used to Predict Atherosclerotic Lesion Localization in Critical Site of the Right Coronary Artery in Patients With Right Dominancy?

BACKGROUND

This study aimed to evaluate the impact of the aorta-right coronary artery angle (ARA) on lesion localization and its protective effect in the critical osteal region in patients with dominant right coronary artery (RCA).

METHODS

This cross-sectional study included 294 patients who underwent elective coronary angiography for stable angina pectoris and had a single significant lumen stenosis (50%-95%) before the RCA crux. Patients with tortuous vessels, previous interventions, left-dominant circulation, or insufficient image quality were excluded. ARA, lesion criticality, length, and distance from the aorto-osteal junction were calculated using quantitative coronary analysis. Patients were categorized based on lesion location: osteal, proximal, mid, and distal regions.

RESULTS

ARA increased significantly as the lesion localization moved distally (osteal: 53.26° ± 5.65°, proximal: 60.79° ± 9.53°, mid: 82.33° ± 9.85°, distal: 93.53° ± 7.46°; p < 0.0001). A strong positive correlation was found between ARA and the distance of the lesion from the aorto-osteal junction (r = 0.759, p < 0.0001). In binary regression, ARA was the only independent risk factor for critical lesion localization in the osteal region (OR = 0.915; 95% CI 0.868-0.965, p < 0.001). ROC analysis showed that an ARA > 73.50° had 83.2% sensitivity and 81.3% specificity for excluding critical lesions in the osteal region (AUC = 0.861; 95% CI 0.815-0.907).

CONCLUSION

A narrow ARA increases the likelihood of critical lesions in the osteal RCA, while an ARA > 73.50° is protective. These findings suggest ARA could guide risk assessment and treatment planning in coronary interventions.