DIRECTIONAL ATHERECTOMY IN ILIAC STENT FAILURE - CLINICAL TECHNIQUE AND HISTOPATHOLOGIC CORRELATION

Purpose: To assess the feasibility and efficacy of directional atherec tomy in the treatment of iliac stent stenosis or occlusion and to eval uate the histologic composition of excised atherectomy specimens. Meth ods: Directional atherectomy of six occluded and 10 severely stenosed iliac stents was undertaken in 12 patients at a mean interval of 28 mo nths (range 3-69 months) after stent insertion for occlusive aortoilia c disease. In cases of stent occlusion, atherectomy was preceded by lo w-dose thrombolysis. In all patients stent clearance with return of fe moral pulses was achieved within 24 hr and there were no significant c omplications. All excised specimens were sent for histologic examinati on. Results: Eleven patients (92%) remain symptom free with unlimited walking distance at a mean follow-up interval of 11.5 months (range 3- 31 months) after treatment. Histologic examination revealed typical my ointimal hyperplasia at three excision sites, intimal fibrosis at thre e sites, atheroma at four sites and organized thrombus at six sites. C onclusion: Atherectomy offers an effective treatment in iliac stent oc clusion and restenosis with no significant-adverse effects. Debulking of these lesions seems to offer a more logical approach than simple ba lloon angioplasty. Clinical and duplex follow-up confirms satisfactory outcome within the first year but longer-term results are not yet kno wn. The histologic data obtained demonstrate that stent restenosis and occlusion are likely to be multifactorial, and challenge the assumpti on that myointimal hyperplasia is the sole cause of iliac stent occlus ion.