Choice Of Optimal Strategy For Bifurcation Lesions With Normal Side Branch (CROSS)

• Diameter stenosis at 8-month follow-up between the kissing balloon inflation and leave alone strategy [ Time Frame: 8 months ] [ Designated as safety issue: No ]
  8 month after PCI
  
  

• Incidence of side branch jail after main vessel stenting according to the stent type used [ Time Frame: Day 1 ] [ Designated as safety issue: No ]
  Day 1 (24 hours after the index procedure)
  
  
• Angiographic reocclusion rate of side branch [ Time Frame: 8 months ] [ Designated as safety issue: No ]
  8month after PCI
  
  
• Angiographic restenosis rate of side branch and the main vessel [ Time Frame: 8 months ] [ Designated as safety issue: No ]
  8month after PCI
  
  
• Late loss of side branch and the main vessel between angiography- and FFR-guided side branch procedure [ Time Frame: 8 months ] [ Designated as safety issue: No ]
  8month after PCI
  
  
• Angiographic reocclusion, restenosis rate and late loss of the side branch according to the DES type [ Time Frame: 8 months ] [ Designated as safety issue: No ]
  8month after PCI
  
  
• Angiographic reocclusion, restenosis rate and late loss of the side branch according to bifurcation angle and bifurcation type [ Time Frame: 8 months ] [ Designated as safety issue: No ]
  8month after PCI
  
  
• Composite of major cardiac adverse events (MACE) including death, MI, stent thrombosis and target vessel revascularization at 12 months [ Time Frame: 12 months ] [ Designated as safety issue: Yes ]
  12month after PCI
  
  
• FFR of the side branch at post-procedure and at follow-up [ Time Frame: Day 1, 8 months ] [ Designated as safety issue: No ]
  Day 1 (immediately after the index procedure)and 8month after PCI
  
  
• Incidence of peri-procedural cardiac enzyme elevation [ Time Frame: Day 1 ] [ Designated as safety issue: No ]
  Day 1 (24 hours after the index procedure)
  
  
• Fluoroscopic time [ Time Frame: Day 1 ] [ Designated as safety issue: No ]
  Day 1 (immediately after the index procedure)
  
  
• Procedure time [ Time Frame: Day 1 ] [ Designated as safety issue: No ]
  Day 1 (immediately after the index procedure)
  
  
• Amount of contrast agent [ Time Frame: Day 1 ] [ Designated as safety issue: No ]
  Day 1 (immediately after the index procedure)
  
  
• Number of used stents [ Time Frame: Day 1 ] [ Designated as safety issue: No ]
  Day 1 (immediately after the index procedure)
  
  

Among the bifurcation type, bifurcation lesion without significant side branch stenosis (<50%) usually did not require side branch stenting, but owing to several putative mechanism including dissection, thrombosis formation, embolization of plaque debris, ostial compromise by displaced stent strut, and snow plow effect, the side branch might be compromised. In this situation, the strategy to achieve optimal results has not been reported. Recently, FFR study showed that most jailed side branch (vessel size >2.0 mm. DS>50%) after main branch stenting did not have functional significance. We compared strategies with or without routine kissing balloon dilatation for less than 50% stenosis after simple DES crossing for bifurcation lesions (bifurcation type 1.1.0, 1.0.0, and 0.1.0 according to Medina classification) with serial change of FFR measurement.