Purpose: Bifurcations lesions represent a challenge for percutaneous coronary interventions (PCI). The provisional SB stenting strategy has emerged as the preferred bifurcation treatment technique. In this strategy, final kissing balloon dilatation (FKBD) is performed. We investigated clinical and angiographic results,and predictors of adverse outcomes after PCI for coronary bifurcations with this 1-stent strategy. Methods: Consecutive patients with non-ST elevation myocardial infarction between January 2010 to November 2012 were included. Inclusion criteria were: coronary bifurcation lesions, a MV diameter 2.5 mm, and SB 2.0 mm. Exclusion criteria were: cardiogenic shock or left main bifurcation. Bifurcation lesions were classified according to the Medina classification. To assess the effect of FKBD after main vessel stenting on clinical and angiographic outcomes in patients undergoing the provisional stenting approach, we selected patients treated with the 1-stent technique in one bifurcation lesion with TIMI III flow result and residual lesion <80% in SB. At this moment the patients were randomized to FKBD and no-FKBD groups. Scheduled coronariography was performed at 6 months follow-up. Results: Finally 100 patients were enrolled (61 in the no-FKBD group and 39 in the FKBD group). The use of DES was similar in both groups and SB predilatation was performed more frequently in the no-FKBD group. Procedural success was similar in both groups. Complete follow-up data were obtained in 100% of the overall population. The incidence of MACE was significantly higher in FKBD group than in no-FKBD group mainly driven by a higher binary restenosis (15.4% vs 0.0% p=0.002) and TLR rate (7.7% vs 0,0% p=0.028). Rates of cardiac death and MI were no significantly different between the two groups. In multivariate analysis the FKBD group was still found to have a significantly higher risk of binary restenosis (OR 34.7, CI 95% 3.4 to 355.9; p=0.003) and SB predilatation (OR 23.2, 95% IC 2.0-269.9; p=0,012). Nevertheles, MV predilatation and the angle of emerging SB were no significantly different between two groups. Conclusions: Based on our results, routine FKBD is not recommended in the 1-stent technique for coronary bifurcation lesions by increased the risk of TLR and MACE, primarily due to increased binary restenosis in the main vessel.