Impact of preinterventional arterial remodeling on neointimal hyperplasia after implantation of (non-polymer-encapsulated) paclitaxel-coated stents: A serial volumetric intravascular ultrasound analysis from the Asian Paclitaxel-Eluting Stent Clinical Trial (ASPECT)

Background-This study used serial volumetric intravascular ultrasound (IVUS) to evaluate the effect of preinterventional arterial remodeling on in-stent intimal hyperplasia (IH) after implantation of non-polymer-encapsulated paclitaxelcoated stents. Methods and Results-Patients were randomized to placebo or one of two doses of paclitaxel (low dose, 1.28 μg/mm²; high dose, 3.10 μg/mm²). Complete preinterventional, post-stent implantation, and follow-up IVUS were available in 18 low-dose and 21 high-dose patients. IH volumes were similar in low-dose and high-dose patients: 17.6 ± mm³ in low-dose patients and 13.1 ± 13.3 mm³ in high-dose patients (P = 0.3). Therefore, IVUS findings in low- and high-dose patients were combined. Preinterventional remodeling was assessed by comparing lesion site to proximal and distal reference arterial area: positive remodeling (lesion > proximal reference, n=13), intermediate remodeling (distal reference < lesion < proximal reference, n = 13), and negative remodeling (lesion < distal reference, n = 13). During follow-up, there was a decrease in lumen volume in positive remodeling lesions (from 106 ± 30 to 90 ± 27 mm³; P = 0.0067) and in intermediate remodeling lesions (from 97 ± 28 to 76 ± mm³; P = 0.0004), but not in negative remodeling lesions (99 ± 27 versus 92 ± 32 mm³; P = 0.15). The follow-up IH volume was lower in negative remodeling lesions (5 ± 7 mm ³) compared with positive remodeling (20 ± 14 mm³; P = 0.0051) and intermediate remodeling lesions (20 ± 15 mm³; P = 0.0043); however, IH volume was virtually identical in positive and intermediate remodeling lesions. Multivariate linear regression analysis determined that remodeling and inflation pressure were independent predictors of IH volume; variables tested in the model included diabetes, acute coronary syndromes, dose, remodeling, and preinterventional plaque burden. Conclusions-Preinterventional arterial remodeling, especially negative remodeling, influences neointimal hyperplasia suppression after implantation of non-polymer-encapsulated paclitaxel-coated stents.