Provisional T-stenting With Ostial Optimization Technique For Coronary Bifurcation Intervention: Insights From Different Balloon Dilation Techniques In A Bench Test

Aim: Provisional T-stenting(PT) is considered as the preferred technique or optimal strategy in coronary bifurcation lesions intervention. How to safely and effectively perform the PT has been widely investigated. Our study is to explore the feasibility of Ostial Optimization Technique(OOT) and optimize the way of double balloon dilation in a bench testing so as to guide the clinical therapy. Methods: The PT and OOT were simulated in a coronary bifurcation model and stent configuration was observed. After stenting of the main branch(MB), OOT was conducted with three different patterns of double balloon dilation, including classical kissing balloon dilation(CKBD), sequential kissing balloon dilation(SKBD) and sequential snuggling balloon dilation(SSBD) prior to stenting the side branch(SB). The stent configuration for the three different treatment of the OOT was observe on polygon of confluence area(POC) and adjacent area(aPOC) by using micro-focus Computerized tomography(MCT) and digital viedo recorder(DVR). The parameters included the degree of "lip evaginating" of the ostial struts, of the residual stent stenosis at the ostial SB, of the stent distortion on the POC and aPOC, and of the stent coverage on the POC and a POC. Results: Three patterns of OOT treatment induced different results: 1) Lip evaginating: there is significant different(p=0.013) in the degree of lip evaginating, with the highest degree of lip evaginating generated by SSBD, followed by SKBD and then by CKBD. 2) Ostial SB opening: there is no statistical differences in the degree of the residual area stenosis(RAS) among the three treatment(p=0.077). 3) The stent distortions: there is significant difference(p=0.027), with the least degree of distortion produced by SSBD, followed by SKBD and then by CKBD. 4) The stent coverage: There is significant difference(p=0.05) on POC, with the best degree of stent coverage afforded by SSBD, followed by SKBD and then by CKBD; while there is no significant difference on the ostial SB(p=0.281) and the ostial MB(p=0.832). Conclusion: Three patterns of OOT treatment induce different ostial optimization result with the best stent lip evaginating, stent opening and converging by SSBD, suggesting that OOT technique particularly SSBD can achieve double-stent effect with mono-stent implanting.