Abstract 9648: Neointimal Tissue Component Assessed by Tissue Characterization With 40MHz Intravascular Ultrasound Imaging - Comparison of Drug-Eluting Stents and Bare-Metal Stents
Background: Drug-eluting stents (DES) can cause impaired arterial healing, which constitutes the most important pathological substrate underlying late DES thrombosis. Intravascular ultrasound (IVUS)-based tissue characterization allows for the in vivo identification of neointimal tissue components. The present study used iMap IVUS system to compare neointimal tissue components between DES and bared-metal stents (BMS).
Methods: Follow-up IVUS data after coronary stenting (9.8±9.4 months from index procedures) was obtained from consecutive 61 lesions (34 in DES, 27 in BMS). Region of interest was placed in neointima hyperplasia and plaque behind stent. The iMap tissue components (fibrotic, lipidic, necrotic, and calcified) were measured in every recorded frame and expressed as percentages of mean neointimal and plaque behind stent cross-sectional area for the stented segment.
Results: Patients' characteristics were comparable between DES and BMS. Compared with BMS, smaller (2.9±0.4mm vs. 3.2±0.4mm, P=0.004) and longer (34±18mm vs. 26±14mm, P=0.03) DES were implanted. Although there was no significant difference in minimum lumen area at follow-up between DES and BMS, average neointimal area was significantly smaller in DES compared with BMS (1.6±0.8mm2 vs. 3.4±2.4mm2, P=0.02). The iMap analyses showed that neointima after DES placement was composed of smaller fibrotic component (70±8% vs. 77±10%, P=0.045), larger necrotic (13±5% vs. 9±3%, P=0.02) and calcified (12±4% vs. 5±4%, P=0.004) components compared with BMS, whereas the plaque component behind stent was identical. Logistic regression analysis showed that only intra-DES neointima was a significant predictor of necrotic neointima at follow-up.
Conclusion: DES implantation would be associated with iMap-derived necrotic and less-fibrotic neointimal formation. In vivo iMap evaluation of neointimal tissue may provide useful information in detecting impaired healing after stenting.
- Intravascular ultrasound/Doppler
- Drug eluting stents
- Interventional cardiology
- Cardiovascular imaging
- © 2011 by American Heart Association, Inc.