Association between the bifurcation angle and the angle of the origin of the left anterior descending with the severity of coronary artery disease.

Abstract

Background: This study aimed to evaluate the association between the bifurcation angle and the angle of the origin of the left anterior descending (LAD) coronary artery with the degree of proximal LAD (pLAD) stenosis.

Methods: This study was cross-sectional and addressed 578 patients suspected of coronary artery disease (CAD) who underwent coronary computed tomography angiography (CCTA) because of angina pectoris symptoms at Shahid Chamran Hospital, Isfahan. PLAD stenosis as well as the left main (LM)-LAD and the LAD-left circumflex artery (LCX) (bifurcation) angles were assessed and recorded on CCTA images. Then, one-way analysis of variance (ANOVA) or chi-squared tests were used. ROC analysis was used to evaluate the diagnostic value of each of the two angles in identifying pLAD stenosis.

Results: Using a cut-off value of 23º for the LM-LAD angle, the sensitivity and specificity for predicting pLAD stenosis <50% were 63.70% and 47.67%, respectively. In addition, using a cut-off value of 30º for the LM-LAD angle, the sensitivity and specificity for predicting pLAD stenosis ≥50% were 52.24% and 68.77%, respectively (P value<0.05). Moreover, for predicting pLAD stenosis <50%, a 49º cut-off for the LAD-LCX angle demonstrated a sensitivity and specificity of 61.64% and 56.99%, respectively. Furthermore, for predicting pLAD stenosis ≥50%, a 50º cut-off for the LAD-LCX angle yielded a sensitivity and specificity of 70.15% and 58.63%, respectively (P value<0.05).

Conclusion: The findings of this study showed that the LAD-LCX and LM-LAD angles had a direct and significant association with the severity of pLAD stenosis, such that wider angles were associated with greater pLAD stenosis.