Background: Restenosis after percutaneous coronary intervention (PCI) for proximal left anterior descending (LAD) artery disease is still a significant clinical problem. Although many risk factors for restenosis after PCI have been identified so far, coronary anatomical characteristics for restenosis have not been fully studied.
Purpose: The aim of this study is to investigate the relationship between LAD bifurcation angle and restenosis after PCI for proximal LAD artery disease.
Methods: We analyzed the data of consecutive 177 patients undergoing PCI for diseased proximal LAD artery, followed by coronary angiography (CAG) from 2008 to 2013. The bifurcation angles between left main trunk and LAD artery (LMT-LAD angles) were measured using left or right anterior oblique (LAO or RAO) caudal view in CAG.
Results: Stent restenoses were found in 33 out of 177 patients. 12 patients had an in-stent restenosis and 21 patients had an in-segment restenosis. The mean LMT-LAD angle was measured as 34.1°±18.5° among all the patients. The average LMT-LAD angle measured in patients with no-restenosis and in-stent restenosis was 32.0°±18.1° and 52.2°±14.5°, respectively, in LAO caudal view with significant difference between these two groups (P<0.001). We also observed that the average LMT-LAD angle in patients with no-restenosis and in-segment restenosis was 17.5°±10.1° and 27.3°±14.3°, respectively, in RAO caudal view (P<0.001). Multivariate analysis showed that indicators for in-stent restenosis were final minimum lesion diameter, lesion length and LMT-LAD angle (OR, 0.12; P=0.036, OR, 10.13; P=0.016 and OR, 7.63; P=0.035, respectively) and indicators for in-segment restenosis were LMT-LAD angle and distance between the ostial LAD artery and proximal edge of stent (OR, 3.83; P=0.024 and OR, 6.37; P=0.006, respectively).
Conclusion: This study suggests that larger LMT-LAD angle is associated with restenosis after stent implantation for proximal LAD artery disease.