Abstract 12950: Comparisons of Neointima Tissue Components Between Cases with Early and Late Target Lesion Revascularization After 1St Generation Drug-Eluting Stents Implantation
Background Although recent pathological studies indicate that neointima tissue after stent implantation comprises heterogeneous components, little is known about the relation between the temporal course of restenosis and neointima tissue components.
Methods: A total of 266 lesions in 184 patients treated with 1st generation drug-eluting stents (DES) underwent mid-term OCT (median: 6.8 months) and were clinically followed for at least one year after the OCT examination (median: 2.9 years, 25percentile: 1.6 years, 75percentile: 4.6 years). Lesions were classified into 3 groups according to the timing of target lesion revascularization (TLR): non-TLR (n=193), early TLR (TLR required < 1 year: median: 209 days, n=54), and late TLR group (TLR required ≥ 1 year: median: 891 days, n=19). Neointima tissue of early and late TLR group was classified into homogeneous (suggestive of matured neointima predominance), layered, and heterogeneous patterns (suggestive of inhomogeneous tissue component such as extracellular matrix, fibrin, and thrombus) by qualitative assessment of mid-term OCT and compared as temporal course of TLR.
Results: Compared with non-TLR group, early and late TLR group had a significantly smaller minimum lumen area and greater neointimal thickness on mid-term OCT images. No significant difference existed in quantitative OCT findings between the early and the late TLR groups on mid-term OCT images. The distribution of morphologic classifications were, however, significantly different. Homogenous patterns were predominant in the early TLR group, while heterogeneous patterns predominated in the late TLR group on mid-term OCT. (Table)
Conclusion: The present study suggested possible involvement of different restenosis mechanisms between cases with early and late DES restenosis. Qualitative assessment of neointima tissue by mid-term OCT may offer incremental information for future time course of restenosis after 1st generation DES.
- © 2012 by American Heart Association, Inc.