Impact of Heterogeneous Overlapping Drug-Eluting Stents on the Arterial Responses of Rabbit Iliac Arteries: A Comparison With Overlapping Bare Metal Stents

BACKGROUND AND OBJECTIVES: Although the use of heterogeneous overlapping drug-eluting stents (DES) is not uncommon in clinical practice, whether the implantation sequences of heterogeneous DES will influence the endothelialization or arterial responses differently remains unclear. MATERIALS AND METHODS: Twenty-one rabbits were randomized to receive overlapping stents in the iliac artery for 3 months {distal sirolimus-eluting stent (SES, Cypher(TM))+proximal paclitaxel-eluting stent (PES, Taxus(TM)) (C+T, n=7), distal Taxus+proximal Cypher (T+C, n=7) and bare metal stent (BMS)+BMS (B+B, n=7)}. Endothelial function was evaluated by the acetylcholine provocation test during follow-up angiography. Histopathological changes in proximal, overlapped, and distal stented segments were evaluated. RESULTS: Although the overall angiographic outcomes were comparable, late loss (mm) in the distal stented segment was higher in the B+B (0.39+/-0.07) and C+T (0.40+/-0.20) than that in the T+C (0.06+/-0.02) group (p<0.001). The incidence of acetylcholine-induced spasm was higher in the DES groups compared with BMS, regardless of the implantation sequences (85.7% in C+T vs. 14.3% in B+B vs. 71.4% in T+C, p=0.017). Notably, only the distal Cypher implantation group (C+T) had three cases of stent fracture. A histopathological analysis showed that despite similar arterial injury scores, Taxus and Cypher stents had higher inflammatory reactions at the overlapped and distal segments compared with those of BMS. CONCLUSION: Despite similar arterial injury, higher inflammatory reactions were observed in overlapping DES segments regardless of the implantation sequence compared with that of BMS. Moreover, DES was associated with impaired endothelial function on the adjacent non-stented segments.

A Novel Technique for Retrieval of a Drug-Eluting Stent After Catheter Break and Stent Loss

Break of a stent delivery catheter and subsequent stent loss (SL) has been a rare event in the drug-eluting stent (DES) era. We here report a case of successful retrieval of a stent after a break if the delivery catheter and SL from a balloon catheter at a culprit lesion. We finally resolved this situation using a simple balloon technique for both the broken stent catheter inside of the guide catheter and the unexpanded stent in the culprit lesion. Thus balloons are an important weapon in our armamentarium in the cardiac catheterization laboratory for urgent retrieval of a lost stent. Their apt use definitely allowed our patient to avoid undergoing emergency cardiovascular thoracic surgery.