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Value of stent placement during percutaneous transluminal angioplasty of the iliac arteries.

BACKGROUND
To determine the benefits of stents during percutaneous transluminal angioplasty (PTA) of the iliac arteries. Retrospective analysis of our 10-year surgical experience with iliac PTA from 1988-1997 permitted comparison of results during two consecutive periods: an initial period (1988-1992), during which stents were never used, followed by a second period (1992-1997), when stenting was performed on indication.


METHODS
From January 1988 to October 1997, 287 iliac PTA procedures (158 common iliac arteries, 129 external iliac arteries) were performed on 250 patients. Thirty-seven patients had two iliac lesions that were treated simultaneously. Indications for PTA included stenosis (270 cases) and chronic occlusion (17 cases). Thirty-one patients (12.4%) underwent infra-inguinal bypass in addition to PTA owing to the existence of arterial lesions at two levels. Two consecutive patient groups were defined: Group I consisted of 75 patients who underwent 86 iliac PTA procedures between January 1988 and May 1992 without stent placement; Group II consisted of 175 patients who underwent 201 iliac PTA procedures between June 1992 and October 1997, when selective stenting was performed. A total of 55 stents (35 in the common iliac artery, 20 in the external iliac artery) were placed in Group II during PTA due to unsatisfactory immediate results (dissection, residual stenosis) or occlusion.


RESULTS
There was no 30-day mortality. There were 15 immediate failures of PTA: 8 in Group I (10.7%) and 7 in Group II (4%). The cumulative initial success rate was 94%. Follow-up ranged from 3 months to 102 months (mean 37 months). The cumulative primary patency rate at 4 years was 62% (58% in Group I, 64% in Group II). The cumulative secondary patency rate at 4 years (including patients who subsequently underwent repeat angioplasty procedures) was 72% (68% in Group I, 74% in Group II).


CONCLUSIONS
Stents were an effective means for treatment of initial failures of PTA in patients with iliac artery occlusive disease. However, there were no significant differences in the long term results between PTA alone and PTA with selective stent placement.