Abstract 16568: Evaluation of an Everolimus-Eluting Dedicated Bifurcation Stent in Comparison with Xience VTM Coronary Stent in a Porcine Coronary Model
Percutaneous coronary interventions of bifurcation lesions are technically demanding and often associated with complications such as dissections. This leads to an increased rate of restenosis, in particular at the side-branch (SB) ostium. This is thought to be due to insufficient support of the side-branch by the stent structure. We studied a newly developed dedicated bifurcation stent (Pathfinder) and compared it to the standard clinically available stent (XIENCE VTM) in a porcine model of coronary bifurcation stenting.
Methods: Stents were implanted in LAD/diagonal and LCX/marginal bifurcations with a stent to artery ratio of 1.1:1 under guidance of 2D and 3D QCA. Each animal received Clopidogrel and ASA throughout the follow-up period (acute, n=9 and 7 days, n=7). Animals received both stent types and all completed the protocol. We assessed the implantation efficacy of the stents by high resolution imaging techniques in vivo (OCT) and ex vivo (microCT), followed by dedicated histology assessment (en-bloc Toluidine blue stained longitudinal sections of the bifurcation, followed by analysis of cross-sections at the carina).
Results: Pathfinder implantation needed less contrast use than XIENCE VTM (26±19 ml vs 63±36 ml, p=0.024). Both stents were uniformly expanded in the main branch (MB). In all cases Pathfinder showed a better SB ostium coverage than the XIENCE VTM, (5±2 struts were counted in SB of arteries receiving a Pathfinder stent, mostly opposite to the flow divider, while no strut was seen in the SB of arteries receiving XIENCE VTM stents, p<0.001). With the small sample size there were no significant differences between Pathfinder and XIENCE in thrombus presence at the struts either acute (11±23% vs 30±38%, p=0.3) or at 7 days (40±34% vs 49±22%, p=0.6), in malapposition (acute: 8±5% vs 18±12%; 7 days: 18±25% vs 4±4%) and endothelial cell coverage of the MB at 7 days (both showed 43% strut coverage with endothelium).
Conclusions: Pathfinder supports the SB ostium better than XIENCE VTM, as evidenced by a preserved diameter on QCA and microCT. It showed similar thrombus formation and strut apposition as compared to XIENCE VTM.
- © 2010 by American Heart Association, Inc.