The impact of the extent of side branch disease on outcomes following bifurcation stenting

Objectives: To define the impact of side branch (SB) lesion length on clinical outcomes after percutaneous coronary intervention (PCI) on bifurcation lesions. Background: The role of the SB lesion length remains questionable in PCI planning and its implication on clinical outcome is controversial. Methods: Data from the retrospective multicenter EBC-P2BiTO registry were analyzed. The primary endpoint was the occurrence of major adverse cardiac events (MACE), defined as the composite of cardiac death, myocardial infarction excluding periprocedural, or stent thrombosis at 13 months median follow-up (IQR 11–28). By using propensity scores for inverse probability of treatment weighting (IPTW), the comparison of treatment groups was adjusted to correct for potential confounding. Results: Among 1,252 patients, SB was normal in 489 (39%), diseased in 763 (61%) cases. MACE occurred in 68 patients (5.4%). The optimal discriminant SB lesion length for MACE was ≥10 mm, with an area under the curve of 0.71 (p <.01). The incidence of MACE was higher among patients with SB lesions ≥10 mm (8%) than with normal SB (4.1%) (hazard ratio [HR], 2.8; 95% confidence interval [CI], 1.5–5.3; p =.001, IPTW-adjusted) or SB lesions <10 mm (5.1%) (HR, 1.5; 95% CI, 1.1–3.3; p =.048, IPTW-adjusted), being similar between these last two groups. Conclusions: In bifurcation PCI, SB lesion length ≥ 10 mm identifies patients at higher risk of MACE than those with <10 mm SB lesions and those without SB disease, considering that no differences were observed among these last two groups. Careful planning is mandatory when approaching bifurcations with long SB lesions.