Revascularization in patients with severe stenosis of left coronary artery (LCAS) trunk signifi cantly improves their prognosis. Modern clinical studies, registries and meta-analyses have identifi ed percutaneous coronary intervention (PCI) of LCAS as a safe alternative to aorto-coronary bypass (ACB) in patients with low and intermediate lesion complexity. Aims: To confi rm the safety and effectiveness of PCI and implantation of second generation drug eluting stent (DES) in patients with unprotected LCAS and concomitant complex coronary pathology. Material and Methods: For the period March 2013–October 2018 we performed 225 PCIs of patients with LCAS. 170 of patients who received PCI were divided into 2 groups, according to their SS-1 (ST elevation excluded). We analyzed the major adverse cardio-vascular events (MACE – all-cause mortality, cardiac mortality, stroke and ischemia driven TLR) rate and time-to-fi rst MACE during follow up. Results: 103 patients had SS-I < 32 and 67 patients had SS-I ≥ 32 and their mean age was 67,25 ± 11,03. The median follow-up was 26,6 ± 19,1 months. MACE rate was 12,4% and there was no signifi cance between groups (p = 0,118). Conclusions: PCI of unprotected LCAS has high procedural success rate and good mid-term results, even in pts with complex anatomy. High anatomical complexity of coronary lesions defi ned by SS-I ≥ 32 is not predictive for poor clinical outcome after PCI.