Impact of a prolonged delivery inflation time for optimal drug‐eluting stent expansion

Abstract

We examined the importance of prolonged inflation time for optimal sirolimus-eluting stent (SES) or paclitaxel-eluting stent (PES) expansion. Eighty-one de novo lesions deployed single SES or PES between April 2007 and March 2008 were divided into four groups; group 1: 21 SES deployed at 20 atm x 60 sec, group 2: 20 SES deployed with 2-step inflation at 20 atm x 60 sec following 20 atm x 20 sec, group 3: 20 PES deployed same as group 1, group 4: 20 PES deployed same as group 2. The minimal lumen diameter (MLD) and stent expansion ratio (SER; stent cross- sectional area at lesion/balloon cross-sectional area which was calculated according to the compliance chart at the same atmosphere as stent deployment) were compared between group 1 and group 2 in SES, between group 3 and group 4 in PES. The MLD of post 60 sec was significantly higher than that of post 20 sec (2.84 +/- 0.28 mm in group 1, 2.76 +/- 0.33 mm in group 2 vs. 2.54 +/- 0.33 mm in group 2; P = 0.003, 0.045, respectively and 2.94 +/- 0.28 mm in group 3, 3.00 +/- 0.34 mm in group 4 vs. 2.69 +/- 0.35 mm in group 4; P = 0.022, 0.007, respectively). The SER of post 60 sec was significantly higher than that of post 20 sec (79.3% +/- 8.5% in group 1, 80.8% +/- 7.8% in group 2 vs. 71.1% +/- 10.2% in group 2; P = 0.014, 0.011, respectively and 81.1% +/- 7.9% in group 3, 84.3% +/- 9.9% in group 4 vs. 72.6% +/- 10.5% in group 4, P = 0.011, 0.001, respectively). The prolonged delivery inflation for 60 sec may result in a more optimal stent expansion. It is therefore considered to be a useful method for deploying drug-eluting stent.