Long-term peripheral stent evaluation using angioscopy

To evaluate incorporation of peripheral artery stents into the arterial wall, we performed angioscopy on 13 patients fitted with Palmaz endoluminal stents. Of the 15 stents inspected, 5 were in the iliac artery, 9 in the femoral artery and 1 in the popliteal artery. The indications for placement were occlusion in 4 cases and high-grade stenosis in 11 cases including 3 restenosis after balloon dilatation and 1 restenosis after surgery. In 9 cases prosthesis insertion was preceded by laser treatment (Trimedyne Nd:YAG Cardiolase 4000). The decision to use a stent was based on radiologic findings in 3 cases (residual stenoses, dissections) and on angioscopic visualization in 7 cases (2 dissections, 5 flaps). In the remaining cases stent placement was performed electively. The only postoperative treatment was antiplatelet therapy (Ticlopidin). At the time of examination, the mean duration of placement was 6 months (extremes: 2 and 12 months). Inspection was made using Sopro-Meadox angioscope with a 0.75 mm probe mounted on an occlusive balloon for stents in the iliac artery and with a 2.2 mm probe with a working channel and sometimes a deflecting device for stents in the femoral or popliteal artery. Angioscopy was successful in all cases. Angiography was always performed at the same time as endoscopy. Endothelialization was observed in all cases. It appeared as a uniform and smooth whitish layer with a thickness proportional to the duration of placement. Endothelialization was most rapid in femoropopliteal arteries, total coverage being achieved within 4 months. Endothelialization took the longest on medial side of the iliac artery which may remain partially exposed after 12 months.(ABSTRACT TRUNCATED AT 250 WORDS)