title: Final proximal post-dilatation is necessary after kissing balloon in bifurcation stenting.
abstract: OBJECTIVE
  High rates of restenosis and stent thrombosis are still often observed after bifurcation stenting despite the recommended stent post-dilatation using the kissing balloon (KB) technique. We investigated the potential benefits of a final post-dilatation step in bifurcation stenting with a balloon that respects the natural diameter ratio of the proximal and distal vessels in bifurcations (Murray's law).
  
  
  RESULTS
  Fourteen commercially available stents (Xience V, Taxus Liberté and Presillion) were deployed in a silicone model of a coronary bifurcation using a provisional stenting approach. After side branch (SB) ostium dilatation and KB inflation, stent geometry and strut apposition was analysed using micro-CT. A final proximal inflation step was then performed to post-dilate only the proximal segment of the main vessel (MV). KB inflation produces an asymmetrical dilatation of the stent in the proximal part of the bifurcation with a number of struts left malapposed in the MV. Using the proposed final proximal inflation (FPI) step reduces the average stent eccentricity index from 0.72 to 0.90 (p<0.001) and the percentage of malapposed struts in the proximal part of the MV from 33.4% to 0.6% (p=0.02), while increasing the minimum stent area from 6.8 mm² to 8.5 mm² (p < 0.0001).
  
  
  CONCLUSIONS
  A final dilatation of the stent only in the MV proximal to the SB with a balloon sized according to the mother vessel is suggested to prevent stent malapposition and optimise stent deployment in bifurcation stenting.
authors.affiliation: Department of Bioengineering, Imperial College London, United Kingdom. nicolas.foin@ic.ac.uk
authors.forename: Nicolas
authors.initials: N
authors.lastname: Foin
authors.forename: Gioel G
authors.initials: GG
authors.lastname: Secco
authors.forename: Liviu
authors.initials: L
authors.lastname: Ghilencea
authors.forename: Rob
authors.initials: R
authors.lastname: Krams
authors.forename: Carlo
authors.initials: C
authors.lastname: Di Mario
mesh_terms: D015906:Angioplasty, Balloon, Coronary / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods; D017023:Coronary Angiography / Q000379:methods; D003331:Coronary Vessels / Q000033:anatomy & histology*; D006801:Humans; D008953:Models, Anatomic; D011474:Prosthesis Design; D012828:Silicones; D015607:Stents; D041623:Tomography, Optical Coherence; D055114:X-Ray Microtomography
chemical_list: D012828:Silicones