Impact of the bifurcation angle on major cardiac events after cross-over single stent strategy in unprotected left main bifurcation lesions: 3-dimensional quantitative coronary angiographic analysis

The impact of the bifurcation angle (BA) between the left main (LM) and the main branch on clinical outcomes after single stenting has never been documented. Therefore, the aim of this study was to investigate the impact of the BA on clinical outcomes after single cross-over LM to left anterior descending artery (LAD) stenting. A total of 170 patients who underwent percutaneous coronary intervention (PCI) in unprotected LM bifurcation with successful single cross-over stenting from the LM into the LAD were enrolled. The main vessel angle between the LM and the LAD was computed in end-diastole before PCI with three-dimensional (3D) quantitative coronary angiography (QCA) software. The patients were classified into three groups according to tertiles of the main vessel angle. The cumulative incidence of major adverse cardiac event (MACE: cardiac death, myocardial infarction, any revascularization including target lesion revascularization) rates throughout a 12-month period were compared between the three groups. Baseline patient characteristics were not a significant difference between the three groups. Compared to the high angle group, the low angle group had a significantly higher incidence of MACE (p = 0.041). In conclusion, this study revealed that low BA between the LM and the LAD had an adverse clinical impact after single cross-over LM to LAD stenting.