Better inflation time of stent balloon for second-generation drug-eluting stent expansion and apposition: An optical coherence tomography study

摘要

Objectives We tried to determine the effect of stent balloon inflation time on stent expansion and apposition using optical coherence tomography. Background Second-generation drug-eluting stents (DES) have thin struts; however, inflation times for optimal stent expansion and apposition are unknown in vivo. Methods Subjects included 17 patients (18 de novo coronary artery lesions), in whom Resolute Integrity-→-(n=9) and Xience Prime-→-(n=9) DES were deployed. All stents were inflated 3 times to the nominal inflation pressure (8.9±0.6-atm) using the stent delivery balloon. The first inflation continued until the stent was angiographically fully expanded; the other 2 lasted 15 and 30-seconds, respectively. Results After the first, second, and third inflation of stent balloon, stent area (5.94±1.7, 6.69±1.8, 7.05±1.8-mm2, P0.001) and stent volume (146.94±59.40, 166.78±69.55, 177.25±69.19-mm3, P0.001) increased significantly. The number of malapposed struts (18.0±17.0, 7.9±10.2, 7.4±10.8, P0.001) and the mean depth of malapposed struts (188.9±75.6, 120.3±101.4, 95.4±86.8-μm, P0.001) decreased. Malapposed stent area (0.62±0.32, 0.52±0.21-mm2, P0.05) and the malapposed stent volume (15.03±7.78, 12.64±5.16-mm3, P0.05) decreased significantly following the second inflation; the third inflation gave no additional benefits to these parameters. There was no adverse clinical outcome after each stent balloon inflation. Conclusions Additional 15-seconds of inflation after the angiographically full expansion of the stent balloon allows better stent expansion and apposition even though the inflation pressure is nominal pressure.