Three-dimensional intravascular ultrasonic volumetric quantification of stent recoil and neointimal formation of two new generation tubular stents

Currently, several different designs of coronary stents are available. However, only a few of the new generation stents have been investigated in large randomized trials. Mechanical behavior of first-generation stents (Palmaz-Schatz, Gianturco-Roubin) may not be applied to the new designs. We investigated the chronic mechanical behavior (recoil) of 2 stents recently approved by the Food and Drug Administration (MULTILINK and NIR). Forty-eight patients with single-stent implantation (23 MULTILINK and 25 NIR) were assessed by means of volumetric 3-dimensional intravascular ultrasound analysis after the procedure and at 6-month follow-up. In addition, volumetric assessment of neointimal formation wets performed. No significant chronic stent recoil was detected in both groups (Delta MULTILINK stent volume: +5.6 +/- 41 mm(3) [p = NS] and Delta NIR stent volume + 2.1 +/- 26 mm(3) [p = NS]). A similar degree of neointimal formation at 6 months was observed between the 2 stents (MULTILINK 46 +/- 31.9 mm(3) vs NIR 39.9 +/- 27.6 mm(3), p = NS). In conclusion, these 2 second-generation tubular stents did not show chronic recoil and appeared to promote similar proliferative response after implantation in human coronary arteries. (C) 2000 by Excerpta Medica, Inc.