Bench Testing And Clinical Study Of Branch Ostial Optimization Treatment And Optimized Provisional T-Stenting

Comparative Analysis between three different Ostial Optimizing Technique in Provisional Bifurcation Stenting:Insights From Micro-Computed Tomographic and Optical Coherence Tomography Imaging of Bench DeploymentsBackground:Coronary bifurcation lesions?CBLs?are still a challenging area in the field of percutaneous coronary intervention?PCI?.Simple strategy with 1-stent or provisional SB stenting has been generally accepted as the default approaches to bifurcation interventions.Nonetheless,it remains controversial whether the kissing balloon dilation?KBD?is necessary and what is the proper way of KBD as using simple strategy.Objective:This study is to evaluate the results of different SB ostial treatments after MB stenting by parallel comparing ostial optimization technique?OOT?,concurrently kissing balloon dilation?KBD?and single balloon dilation?SBD?.Methods:After the PMV-MB stenting,the three ways of the ostial SB treatment?SBD,KBD and OOT?were emulated in a polyvinyl alcohol bifurcated phantom,in which PMV was 3.5 mm,MB 3.25mm,SB 3.0mm with distal bifurcated angle of 45°.The procedures were recorded by a high resolution digital video recorder,and all bifurceted phantoms were examined by micro computed tomography?Micro-CT?and optical coherence tomography?OCT?.The following stent performance indices were assessed with Micro-CT:reference(A_REF)and minimal(A_MIN)stent area,length of the valgus struts(L_VS)and neocarina(L_NC),ostial area of MB(A_MBO)and SB(A_SBO),angulation between the MB and valgus struts axes(A_VS),stent lumen eccentricity index?EI?,index of stent cell distortion(I_SCD).Additionally,the rate of severe strut malapposition(R_SMA)was calculated by OCT.Results:As compared to the non-OOT procedure?SBD and KBD?,OOT created longer L_VS?OOT:2.13±0.30 mm,SBD:1.23±0.34 mm,KBD:1.11±0.39 mm,P<0.01?,broader A_VS?OOT:42.72±0.91°,SBD:25.77±7.81°,KBD:28.98±4.65°,P<0.01?,shorter L_NC?OOT:0.28±0.31 mm,SBD:0.64±0.38 mm,KBD:1.11±0.37 mm,P<0.01?,larger A_MBO?OOT:10.69±0.74 mm²,SBD:9.68±0.62 mm²,KBD:9.61±0.93mm²,P=0.052?and A_SBO?OOT:6.76±0.17 mm²,SBD:4.78±0.86 mm²,KBD:5.87±0.89 mm²,P<0.01?,lower I_SCD?OOT:6.67±3.33%,SBD:10.67±4.23%,KBD:20.00±5.29%,P<0.01?and better EI in PMV segement?OOT:1.07±0.01,SBD:1.06±0.04,KBD:1.14±0.05,P<0.01?.Equally,in the BCD segement,the rate of severe strut malapposition(R_SMA)was less in OOT procedure compared with non-OOT procedure?OOT:2.22±0.48%,SBD:10.31±0.66%,KBD:6.74±1.24%,P<0.01?.Conclusions:A sequential snuggling balloon dilation plus final POT,namely“OOT”,achieved the best optimization of SB ostium in coronary bifurcations,which may significantly reduce the risk of in-stent restenosis?ISR?and in-stent thrombosis?IST?.Branch Ostial Optimization Treatment and Optimized Provisional T-Stenting of Cronary Bifurcations: Ex Vivo Morphologic and Hemodynamic Examination with Polymeric Bioresorbable Scaffolds and Drug Eluting StentsBackground: Although provisional side-branch?SB?stenting is accepted as the default approach for bifurcation intervention in drug-eluting stent?DES?and bioresorbable vascular scaffold?BVS?era,the optimal technique remains a subject of debate as necessary for rescue SB stenting.Objective: In this study,we proposed a novel optimized provisional T-stenting technique?OPT?and assessed its feasibility by comparison with classic provisional Tstenting?CPT?using DES and BVS.Methods: Two provisional SB stenting techniques?OPT and CPT?were emulated in a bifurcated phantom using DES and BVS,respectively.Prior to SB scaffolding,a key step,the sequential intermediate snuggling balloon dilation,was added to OPT to optimize the SB ostium but not to CPT and finalized with the final snuggling balloon dilation for both procedures.Micro-computed tomography?MCT?and optical coherence tomography?OCT?were performed to assess stent/scaffold morphologies,and computational fluid dynamics?CFD?to hemodynamics in the scaffolded bifurcations focused on bifurcation connecting domain?BCD?.Results: As compared to CPT,OPT created shorter neo-carina length?DES group: 0.27±0.16 mm vs.1.51±0.38 mm,P<0.01;BVS group: 0.34±0.10 mm vs.1.02±0.26 mm,P<0.01?,longer valgus struts length?DES group: 1.92±0.21 mm vs.0.91±0.09 mm,P<0.01;BVS group: 2.49±0.27 mm vs.1.78±0.33 mm,P<0.01?with broader AVS?DES group: 45.63±3.60° vs.33.35±9.03°,P<0.05;BVS group: 55.00±4.18° vs.46.20±6.14°,P < 0.05?,larger MB ostial area?DES group: 9.82±0.41 mm2 vs.8.91±0.52 mm2,P<0.05;BVS group: 9.46±0.04 mm2 vs.8.34±0.09 mm2,P<0.01?and lower rate of severe strut malapposition?DES group: 2.47±0.31% vs.11.12±0.75%,P<0.01;BVS group: 13.20±0.16% vs.1.94±0.54%,P<0.01?in BCD.Additionally,CFD revealed that OPT generated more favorable flow pattern indicated by smaller area?14.41±4.51 mm2 vs.26.60±5.02 mm2,P<0.01?with less percent?4.68±1.40 % vs.8.88±1.21%,P<0.01?of low wall shear stress?<0.4 Pa?on the branches lateral walls,and by less decrease of bifurcation flow velocity with fewer disturbed streamlines or turbulent field near the neo-carina.Conclusions: Regardless of treatment with DES or BVS,OOT is feasible for optimizing ostial SB and facilitating subsequent SB scaffolding,OPT is better than CPT in terms of bifurcated morphologies and hemodynamics.Efficacy and Safety of Provisional 1-stent Technique with or without Branch Ostial Optimization Techniques for Treatment of True Bifurcation Lesions: A Propensity Matched AnalysisBackground: Provisional T-stenting has been the default approach to bifurcation intervention with or without SB stenting.It is uncertain whether final kissing balloon dilation?FBKD?is necessary when using provisional T-stenting as the initial interventional strategy.Objective: This study sought to compare the 1-year clinical outcomes of provisional 1-stent with or without branch ostial optimization techniques for treatment of true coronary bifurcation lesions.Methods: One hundred and ninety eight consecutive patients with true bifurcation lesions were enrolled from our hospital between January 2004 and December 2006.Patients were divided into two groups: those treated with ostial optimization techniques?OOT?after main-vessel?MV?stenting?OOT group,n=50?vs.those treated without OOT after MV stenting?non-OOT group,n=148?.The primary end point was major adverse cardiac events?MACE?: including cardiac death,myocardial infarction?MI?,or target vessel revascularisation?TVR?at 1-year followup.Propensity score matching was performed to blance the siginificant differences among the baseline clinical characteristics between the two groups.Results: After propensity score matching,there were 43 patients in each group.The non-OOT group had higher rates of MACE than OOT group at 1 year?2.3% vs.14.0%,P=0.047?,the rate of TVR was 11.6% versus 2.3%?P=0.086?in the non-OOT and OOT groups,respectively.The rate of MI were similar in both groups?2.3% in the non-OOT group vs 2.3% in the OOT group,P=0.958?.Additionally,the rate of restenosis in MV was 27.35±11.38%?non-OOT?versus 13.16±3.56%?OOT,P < 0.01?,and in sidebranch was 33.82±14.89%?non-OOT?versus 13.80±3.86%?OOT,P<0.01?.Conclusions: Provisional 1-stenting with OOT for treatment of true bifurcation lesions is feasible and safe,with low rate of MACE and restenosis.