Predictors and outcomes of side branch occlusion after main vessel stenting in coronary bifurcation lesions: results from the COBIS II Registry (COronary BIfurcation Stenting).

OBJECTIVES This study sought to investigate the predictors and outcomes of side branch (SB) occlusion after main vessel (MV) stenting in coronary bifurcation lesions. BACKGROUND SB occlusion is a serious complication that occurs during percutaneous coronary intervention (PCI) for bifurcation lesions. METHODS Consecutive patients undergoing PCI using drug-eluting stents for bifurcation lesions with SB ≥2.3 mm were enrolled. We selected patients treated with the 1-stent technique or MV stenting first strategy. SB occlusion after MV stenting was defined as Thrombolysis in Myocardial Infarction flow grade <3. RESULTS SB occlusion occurred in 187 (8.4%) of 2,227 bifurcation lesions. In multivariate analysis, independent predictors of SB occlusion were pre-procedural percent diameter stenosis of the SB ≥50% (odds ratio [OR]: 2.34; 95% confidence interval [CI]: 1.59 to 3.43; p < 0.001) and the proximal MV ≥50% (OR: 2.34; 95% CI: 1.57 to 3.50; p < 0.001), SB lesion length (OR: 1.03; 95% CI: 1.003 to 1.06; p = 0.03), and acute coronary syndrome (OR: 1.53; 95% CI: 1.06 to 2.19; p = 0.02). Of 187 occluded SBs, flow was restored spontaneously in 26 (13.9%) and by SB intervention in 103 (55.1%) but not in 58 (31.0%). Jailed wire in the SB was associated with flow recovery (74.8% vs. 57.8%, p = 0.02). Cardiac death or myocardial infarction occurred more frequently in patients with SB occlusion than in those without SB occlusion (adjusted hazard ratio: 2.34; 95% CI: 1.15 to 4.77; p = 0.02). CONCLUSIONS Angiographic findings of SB, proximal MV stenosis, and clinical presentation are predictive of SB occlusion after MV stenting. Occlusion of sizable SB is associated with adverse clinical outcomes..