Background - The aim of this study was to evaluate the relationship between residual plaque burden after coronary stent implantation and the development of late in-stent neointimal proliferation. Methods and Results - Between January 1996 and May 1997, 50 patients underwent intravascular ultrasound (IVUS) interrogation at 6±1.2 months after coronary stent implantation in native coronary arteries. IVUS images were acquired with a motorized pullback, and cross-sectional measurements were performed within the stents at 1-mm intervals. The following measurements were obtained: (1) lumen area (LA), (2) stent area (SA), (3) area delimited by the external elastic membrane (EEMA), (4) percent neointimal area calculated as (SA- LA/SA)X100, and (5) percent residual plaque area calculated as (EEMA- SA)/EEMAX100. Volume measurements within the stented segments were calculated by applying Simpson's rule. In the pooled data analysis of 876 cross sections, linear regression showed a significant positive correlation between percent residual plaque area and percent neointimal area (r=0.50, y=45.03±0.29x, P<0.01). There was significant incremental increase in mean percent neointimal area for stepwise increase in percent residual plaque area. Mean percent neointimal area was 16.3±10.3% for lesions with a percent residual plaque area of <50% and 27.7±11% for lesions with a percent residual plaque area of ≥50% (P<0.001). The volumetric analysis showed that the percent residual plaque volume was significantly greater in restenotic lesions compared with nonrestenotic lesions (58.7±4.3% versus 51.4±5.7%, respectively; P<0.01). Conclusions - Late in-stent neointimal proliferation has a direct correlation with the amount of residual plaque burden after coronary stent implantation, supporting the hypothesis that plaque removal before stent implantation may reduce restenosis.
ASJC Scopus subject areas
- Cardiology and Cardiovascular Medicine
- Physiology (medical)