Angiographic and intravascular ultrasound predictors of in-stent restenosis

Objectives. This study was performed to determine predictors of in-stent restenosis from high volume, single-center practice. Background. Intracoronary stents have been shown to reduce the restenosis rate as compared with balloon angioplasty, but in-stent restenosis continues to be an important clinical problem. Methods. Between April 1993 and March 1997, 1,706 patients with 2,343 lesions were treated with variety of intracoronary stents. The majority of stents were placed with high pressure balloon inflations and intravascular ultrasound (IVUS) guidance. Angiographic follow-up was obtained in 1,173 patients with 1,633 lesions (70%). Clinical, angiographic and IVUS variables were prospectively recorded and analyzed by univariate and multivariate models for the ability to predict the occurrence of in-stent restenosis defined as diameter stenosis ≥50%. Results. In-stent restenosis was angiographically documented in 282 patients with 409 lesions (25%). The restenosis group had significantly longer total stent length, smaller reference lumen diameter, smaller final minimal lumen diameter (MLD) by angiography and smaller stent lumen cross-sectional are (CSA) by IVUS. In lesions where IVUS guidance was used, the restenosis rate was 24% as compared with 29% if IVUS was not used (p < 0.05). By multivariate logistic regression analysis, longer total stent length, smaller reference lumen diameter and smaller final MLD were strong predictors of in-stent restenosis. In lesions with IVUS guidance, IVUS stent lumen CS was better independent predictor than the angiographic measurements. Conclusions. Achieving an optimal stent lumen CS by using IVUS guidance during the procedure and minimizing the total stent length may reduce in-stent restenosis.