Clinical impact of bifurcation angle change between diastole and systole in complex stenting for left main distal bifurcation: The Milan and New-Tokyo (MITO) Registry

Objectives: We assessed the impact of pre-percutaneous coronary intervention (PCI) bifurcation angle change (BAC) on clinical outcomes. Background: There are little available data about the impact of BAC in unprotected left main distal bifurcation lesions (ULMD) PCI. Methods: We identified consecutive 300 patients with ULMD underwent complex stenting using drug-eluting stent in three high-volume centers (Tokyo and Milan). We measured the widest BA of ULMD at both end-diastole and end-systole before stenting with two-dimensional quantitative coronary angiographic assessment and calculated the BAC value as a difference of two BA value in each lesion. We divided them into small and large BAC group according to the median BAC value (7.2°). The primary endpoint was target lesion failure (TLF), which was defined as a composite of cardiac death, target lesion revascularization (TLR) and myocardial infarction. Results: TLF rate at 3-year was significantly higher in the large BAC group than in the small BAC group (adjusted hazard ratio [HR] 5.85; 95% confidence interval [CI], 3.40–10.1; p <.001). TLR rate for left main (LM) to left anterior descending artery (LAD) and ostial left circumflex artery (LCXos) at 3-year were significantly higher in large BAC group than in small BAC group (adjusted HR 5.91; 95% CI, 2.03–17.2; p =.001 and adjusted HR 10.6; 95% CI, 5.20–21.6; p <.001, respectively). Conclusions: A large BAC before stenting is strongly associated with adverse events after complex stenting for ULMD, mainly driven by repeat PCI for restenosis of the LCXos and of the LM-LAD.