Abstract 4160: Repeated 3-times-balloon-inflation for Stent Deployment Increases Luminal Patency of Cobalt Alloy Stent: In vitro Study Using 75% Stenotic Mechanically-equivalent Coronary Artery Replica
Introduction: We have developed a stenotic coronary artery replica, and investigated optimal deployment method of cobalt alloy stent to increase post-procedural minimal lumen diameter (MLD) and minimal luminal cross-sectional area (CSA).
Methods: Diseased coronary artery replica with a reference vessel diameter of 3.0 mm was developed. The replica equips a concentric 75 % stenosis with 10 mm stenotic length. Clinical data of stent recoil (SR) and stent delivery balloon underexpansion (SDBU) of cobalt alloy stent (Driver, Medtronic) were referenced. Mechanical properties of the stenotic lesion were regulated to match SR and SDBU between in-vivo and in-vitro data. Delivered in the mechanically-equivalent stenotic replica, Driver stent (3.0mm×18mm) was expanded at 16 atm, and the influence of prolonged delivery balloon inflation time on MLD and CSA was investigated among 20 sec (n=112), 40 sec (n=12), and 60 sec (n=12), respectively. Moreover, an influence of repeated balloon inflation with 16 atm for 20 sec on MLD and CSA was explored among 1 time (n=112), 2 times (n=62), and 3 times (n=62). MLD and CSA were measured using intravascular ultrasound (IVUS, iLab, Boston Scientific).
Results: Prolonged balloon inflation time for 40 sec and 60 sec increased MLD and CSA (p<0.001 each) as compared with 20 sec inflation. Moreover, the repeated inflation for 2 or 3 times increased MLD and CSA (p<0.001 each) against 1 time stent deployment. Larger MLD and CSA after 3 times 20-sec inflation were obtained in comparison with 1 time 60-sec inflation (p<0.05 each).
Conclusions: The data suggest that 3 times balloon inflation for 20 sec impact on increasing MLD and CSA of cobalt alloy coronary stent.