Angiographic pattern of restenosis following implantation of overlapping sirolimus-eluting (Cypher) stents
Sirolimus-eluting stents (Cypher) have been shown to reduce the frequency of neointimal hyperplasia and restenosis compared with bare metal stents. However, the clinical implication of overlapping stents with regard to the pattern of restenosis is unclear. All patients who underwent angiography at our institution from May 2003 to March 2005 who had previously received 2 overlapping Cypher stents in native coronary lesions and had binary restenosis were included in our study. Quantitative coronary analysis was performed to determine the degree and location of the restenotic lesion with respect to the overlapping stented segment. The primary end point was to determine how often restenotic lesions occurred at the overlapped segment versus the nonoverlapped stented segments. During the study, 11 patients fit the inclusion criteria for our study; 91% were men and 55% had diabetes mellitus. The mean total stent length was 33.7 +/- 8.2 mm. The mean length of the overlapped segment was 5.9 +/- 3.8 mm, equating to 19 +/- 16% of the total stented area. The average time to follow-up angiography was 277 +/- 126 days. All 11 lesions exhibited type 1 (focal) restenosis. Of these 11 lesions, 10 had focal restenosis at the overlapped segment (p = 0.01, binomial test). The single case involving in-stent restenosis in the nonoverlapped segment occurred at the proximal stent edge. In conclusion, the pattern of restenosis observed in our study suggests a higher relative incidence of binary restenosis in the overlapped stented segment in patients who receive 2 overlapping Cypher stents.