Side-Branch Intervention After Crossover Stenting for Medina 0.0.1 and 0.1.0 Left Main Bifurcation Lesions (The Multicenter SIBIS Study).

The clinical value of routine side-branch intervention (SBI) following crossover stenting (CSI) for Medina 0.0.1 or 0.1.0 left main (LM) bifurcation lesions remains uncertain because randomized evidence is lacking and observational data are limited. We evaluated whether systematic SBI after CSI improves long-term clinical outcomes in this setting. This multicenter retrospective study included 871 patients (72% men; mean age 63.8 ± 12.5 years) who underwent CSI for Medina 0.0.1 or 0.1.0 LM bifurcation lesions at 13 high-volume centers between 2012 and 2026. Patients were divided according to whether SBI was performed (SBI, n = 229) or not (no-SBI, n = 642). The primary endpoint was major adverse cardiac events, defined as the composite of cardiac death, target lesion revascularization, and target vessel myocardial infarction. Baseline lesion complexity, including Synergy Between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery score, intravascular imaging use, and maximum postdilatation balloon diameter, was similar between the 2 groups. Compared with the no-SBI group, the SBI group had a higher rate of bailout 2-stent conversion (8.7% vs 4.4%, p = 0.013), greater contrast use (211.7 ± 84.1 vs 191.7 ± 99.2 ml, p = 0.002), and longer procedure time (55.3 ± 23.1 vs 46.7 ± 17.8 minutes, p <0.001). After multivariable adjustment, long-term major adverse cardiac events did not differ between the 2 groups (hazard ratio 1.28, 95% confidence interval 0.77 to 2.13, p = 0.350). In conclusion, in patients undergoing CSI for Medina 0.0.1 or 0.1.0 LM bifurcation lesions, systematic SBI was not associated with improved long-term clinical outcomes and was associated with greater procedural complexity. These findings do not support the routine use of SBI in this setting and should be considered hypothesis-generating.