We assessed 100 pts treated with drug eluting stents(DES). Virtual histology intravascular ultrasound (VH-IVUS) imaging was performed before and after DES implantation. Thin-capped fibroatheroma (TCFA) was defined as necrotic core(NC) >10% of plaque area within a plaque burden of >40% and NC in contact with the lumen for at least 3 image slices. TCFAs were compared to non-TCFA lesions (all other VH-IVUS lesion types including thick-capped fibroatheromas and fibrocalcific plaques). Stent strut artifacts were manually excluded. Positive remodeling was defined as a remodeling index (lesion/reference external elastic membrane area) >1.05. Results. Pt age was 62짹10yrs and 70% were males in TCFA group; pt age was 60짹13yrs and 75% were males 75% in non-TCFA group. Greyscale IVUS showed that TCFA and non-TCFA had similar distal reference lumen area (7.05짹2.15mm2 vs 6.97짹2.44mm2, p=0.92) and lesion length (19.1짹7.36mm vs 19.5짹6.52mm, p=0.77). Remodeling index was 1.01짹0.13 in TCFA vs 0.97짹0.12 in non-TCFA, p=0.46. Pre-DES %average NC (p=0.013) and %maximal NC (p=0.001) were higher in TCFA vs non-TCFA (Table). After DES implantation VH-IVUS showed that the NC was more often in contact with lumen in TCFA (13/30 [43%]) than in non-TCFA (6/32 [18.7%], p=0.034). Similarly, post DES implantation, the %maximal NC was still larger in TCFA than non-TCFA (Table). Conclusion. DES implantation into a TCFA results in NC in contact with the lumen in almost 50% of lesions. These may be at higher risk of subsequent events because of impaired healing response.