Acute stent recoil and optimal balloon inflation strategy: an experimental study using real-time optical coherence tomography.
OBJECTIVE
Our aim was to evaluate stent expansion and acute recoil at deployment and post-dilatation, and the impact of post-dilatation strategies on final stent dimensions.


RESULTS
Optical coherence tomography (OCT) was performed on eight bare metal platforms of drug-eluting stents (3.0 mm diameter, n=6 for each) during and after balloon inflation in a silicone mock vessel. After nominal-pressure deployment, a single long (30 sec) vs. multiple short (10 sec x3) post-dilatations were performed using a non-compliant balloon (3.25 mm, 20 atm). Stent areas during deployment with original delivery systems were smaller in stainless steel stents than in cobalt-chromium and platinum-chromium stents (p<0.001), whereas subsequent acute recoil was comparable among the three materials. At post-dilatation, acute recoil was greater in cobalt-chromium and platinum-chromium stents than in stainless steel stents (p<0.001), resulting in smaller final stent areas in cobalt-chromium and platinum-chromium stents than in stainless steel stents (p<0.001). In comparison between conventional and latest-generation cobalt-chromium stents, stent areas were not significantly different after both deployment and post-dilatation. With multiple short post-dilatations, acute recoil was significantly improved from first to third short inflation (p<0.001), achieving larger final area than a single long inflation, despite stent materials/designs (p<0.001).


CONCLUSIONS
Real-time OCT revealed significant acute recoil in all stent types. Both stent materials/designs and post-dilatation strategies showed a significant impact on final stent expansion.
Division of Cardiovascular Medicine, Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, USA.
Hideki
H
Kitahara
Katsuhisa
K
Waseda
Ryotaro
R
Yamada
Kyuhachi
K
Otagiri
Shigemitsu
S
Tanaka
Yuhei
Y
Kobayashi
Kozo
K
Okada
Teruyoshi
T
Kume
Kaori
K
Nakagawa
Tomohiko
T
Teramoto
Fumiaki
F
Ikeno
Paul G
PG
Yock
Peter J
PJ
Fitzgerald
Yasuhiro
Y
Honda
D015906:Angioplasty, Balloon, Coronary / Q000379:methods; D017023:Coronary Angiography / Q000379:methods; D003331:Coronary Vessels / Q000601:surgery*; D054855:Drug-Eluting Stents; D005260:Female; D006801:Humans; D008297:Male; D011474:Prosthesis Design; D013997:Time Factors; D041623:Tomography, Optical Coherence / Q000379:methods