The importance of proximal optimization technique with intravascular imaging guided for stenting unprotected left main distal bifurcation lesions: The Milan and New-Tokyo registry

Objectives This study evaluated the 5-years outcomes of intracoronary imaging-guided proximal optimization technique (POT) for percutaneous coronary intervention (PCI) in patients with unprotected left main distal bifurcation lesions (ULMD). Background The long-term effects of POT with intracoronary imaging guide in PCI for ULMD have been unclear. Methods Between January 2005 and December 2015, we identified 1832 consecutive patients who underwent DES implantation for ULM distal bifurcation lesions. Of them, 780 (56.1%) patients underwent POT with intravascular imaging guidance (optimal expansion group). Residual 611 (43.9%) patients did not undergo either POT or intravascular imaging or both (suboptimal expansion group). Analysis using propensity score adjustment was performed. The primary endpoint was target lesion failure (TLF) defined as a composite of cardiac death, target lesion revascularization (TLR), and myocardial infarction. Results TLF rate at 5 years was significantly lower in optimal expansion group than that in suboptimal expansion group [adjusted HR 0.65, 95% CI (0.48-0.87), p = 0.004]. Cardiac mortality was significantly lower in optimal expansion group than that in suboptimal expansion group [adjusted HR 0.46, 95% CI (0.27-0.79), p = 0.004]. The multivariable analysis identified POT with intravascular imaging guide [adjusted HR 0.65, 95% CI (0.48-0.87), p = 0.004] as an independent predictor of TLF. Conclusions Intravascular imaging guided POT was strongly associated with the reduced risk of TLF at 5 years after PCI for ULMD, mainly driven by reducing cardiac mortality.