BACKGROUND: The clinical impact of late incomplete stent apposition (ISA) for drug-eluting stents is unknown. We sought to prospectively investigate the incidence and extent of ISA after the procedure and at 6-month follow-up of paclitaxel-eluting stents in comparison with bare metal stents (BMS) and survey the clinical significance of ISA over a period of 12 months. METHODS AND RESULTS: TAXUS II was a randomized, double-blind study with 536 patients in 2 consecutive cohorts comparing slow-release (SR; 131 patients) and moderate-release (MR; 135 patients) paclitaxel-eluting stents with BMS (270 patients). This intravascular ultrasound (IVUS) substudy included patients who underwent serial IVUS examination after the procedure and at 6 months (BMS, 240 patients; SR, 113; MR, 116). The qualitative and quantitative analyses of ISA were performed by an independent, blinded core laboratory. More than half of the instances of ISA observed after the procedure resolved at 6 months in all groups. No difference in the incidence of late-acquired ISA was observed among the 3 groups (BMS, 5.4%; SR, 8.0%; MR, 9.5%; P=0.306), with a similar ISA volume (BMS, 11.4 mm3; SR, 21.7 mm3; MR, 8.5 mm3; P=0.18). Late-acquired ISA was the result of an increase of vessel area without change in plaque behind the stent. Predictive factors of late-acquired ISA were lesion length, unstable angina, and absence of diabetes. No stent thrombosis occurred in the patients diagnosed with ISA over a period of 12 months. CONCLUSIONS: The incidence and extent of late-acquired ISA are comparable in paclitaxel-eluting stents and BMS. ISA is a pure IVUS finding without clinical repercussions.

Aged, Coated Materials, Biocompatible/therapeutic use, Female, Humans, Incidence, Male, Middle aged, Paclitaxel/*administration & dosage, Prosthesis Implantation/adverse effects/*standards, Risk Factors, Stents/*adverse effects, Ultrasonography, Interventional,
Circulation (Baltimore)
Epub 2005 Feb 14
Erasmus MC: University Medical Center Rotterdam

Tanabe, K, Serruys, P.W.J.C, Degertekin, M, Grube, E, Guagliumi, G, Urbaszek, W, … Colombo, A. (2005). Incomplete stent apposition after implantation of paclitaxel-eluting stents or bare metal stents: insights from the randomized TAXUS II trial. Circulation (Baltimore), 111(7), 900–905. doi:10.1161/01.CIR.0000155607.54922.16