Impact of 3-dimensional bifurcation angle on 5-year outcome of patients after percutaneous coronary intervention for left main coronary artery disease: A substudy of the SYNTAX trial (Synergy between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery)

Objectives This study sought to investigate the impact of left main coronary artery (LMCA) 3-dimensional (3D) bifurcation angle (BA) parameters on 5-year clinical outcomes of patients randomized to LMCA percutaneous coronary intervention (PCI) in the SYNTAX (Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery) trial. Background BA can affect outcome after bifurcation PCI; 3D angiographic analysis provides reliable BA measurements. Methods The diastolic distal BA (between left anterior descending and left circumflex) and its systolic-diastolic range were explored. A stratified post-hoc survival analysis was performed for 5-year major adverse cardiac and cardiovascular events (MACCE) (all-cause death, cerebrovascular accident, myocardial infarction, or repeat revascularization), a safety endpoint (all-cause death, cerebrovascular accident, or myocardial infarction), and repeat revascularization. Analysis was performed in patients where 3D BA was available pre- and post-PCI. Results Of 266 patients eligible for analysis, 185 underwent bifurcation PCI (group B); 1 stent was used in 75 patients (group B1), whereas ≥2 stents were used in 110 patients (group B2). Stratification across pre-PCI diastolic distal BA tertiles (<82, 82 to 106, ≥107) failed to show any difference in MACCE rates either in the entire study population (p = 0.99) or in group B patients (p = 0.78). Group B patients with post-PCI systolic-diastolic range <10 had significantly higher MACCE rates (50.8% vs. 22.7%, p < 0.001); repeat revascularization and safety endpoint rates were also higher (37.4% vs. 15.5%, p = 0.002, and 25.4% vs. 14.1%, p=0.055, respectively). Post-PCI systolic-diastolic range <10 was an independent predictor of MACCE (hazard ratio: 2.65; 95% confidence interval: 1.55 to 4.52; p < 0.001) in group B patients. Conclusions A restricted post-procedural systolic-diastolic distal BA range resulted in higher 5-year adverse event rates after LMCA bifurcation PCI. Pre-PCI BA value did not affect the clinical outcome.