Vascular responses to the multiple overlapped paclitaxel-eluting stents for the treatment of bare-metal in-stent restenotic lesions: angiographic and intravascular ultrasound analysis from the TAXUS-V ISR Trial

BackgroundAlthough effective coverage of coronary diffuse in-stent restenosis (ISR) lesions has warranted the use of multiple drug-eluting stents, the vessel response to paclitaxel-eluting stent (PES) overlap is not fully understood.Methods and materialsIn the TAXUS-V ISR, i.e., comparing PES versus brachytherapy for the treatment of bare-metal ISR, angiographic analyses at 9-month follow-up were available in 184 ISR lesions treated with PES.ResultsIn-stent late loss in entire stented segment of multiple PES (n=50) was 0.45±0.48 mm, whereas that of single PES (n=134) was 0.3±0.47 mm, P=.06. No aneurysm was observed at overlapping PES segments at 9 months. Stent thrombosis up to 9 months was observed in one in each group (single PES, 0.7% vs. multiple PES, 1.8%; P=.47). In a subset of 30 patients, volumetric intravascular ultrasound analysis demonstrated that in-stent net volume obstruction was 12.3±12.4 in single PES (n=20) and 14.9±9.8 in multiple PES (n=10), P=.60. The changes of vessel and lumen at the overlapping PES segment were similar to those of the adjacent 5-mm segments (Δminimum lumen area, mm2: −1.2±1.0, −1.1±1.1, −0.8±0.9, P=.48; Δvessel volume, mm3/mm: −0.2±1.4, 0.1±1.7, 0.3±1.3, P=.37; proximal, overlap, distal segment, respectively). There was no late incomplete stent apposition at overlapping PES segments.ConclusionsNo in vivo evidence of adverse local vessel response at the site of overlapping PES for the treatment of bare-metal ISR has been demonstrated.