Efficacy of treatment of severe carotid bifurcation stenosis by using self-expanding stents without deliberate use of angioplasty balloons.

BACKGROUND AND PURPOSE

One of the limitations of carotid artery angioplasty is the potential for embolic stroke. Our purpose was to assess whether the force of a self-expanding stent alone is usually sufficient to dilate severely stenotic atherosclerotic plaques without the deliberate use of an angioplasty balloon. If so, the procedural stroke risk might be reduced.

METHODS

Over a 30-month period, 21 consecutive patients were prospectively identified with severe symptomatic carotid artery stenosis (>70% NASCET [North American Symptomatic Carotid Endarterectomy Trial]) and relative indications for endovascular treatment. All underwent treatment with the aim of deploying a self-expanding stent across the stenosis without the use of angioplasty balloons or distal protection devices.

RESULTS

Stent deployment was successful in 20/21 patients. In one patient, the stent could not be deployed without balloon predilatation and a stroke occurred. In the other 20 patients, angiography before and immediately after stent deployment showed a reduction in the mean stenosis from 83% to 49%. A second periprocedural stroke occurred as a result of early stent thrombosis at 4 days in a patient who stopped Acetylsalicylic acid while undergoing bowel preparation for colon surgery. He made a good recovery. Average duration of follow-up imaging was 19 months (range, 1-44 months). During the follow-up period there were four deaths, all unrelated to the carotid disease, and no major strokes. At 5-11 months, the average residual stenosis was 21%, which remained stable in 16 of the 18 patients studied between 12 and 44 months (average, 24 months). At last follow-up, in these 16 the mean peak systolic velocity was 123 cm/s (range, 60-238 cm/s) and the mean internal-to-common carotid ratio was 1.8. The other two patients were long-term failures of the "stent-only" approach. In one patient, a heavily calcified plaque prevented stent expansion and the artery occluded at 18 months with a minor stroke. In the second patient, a recurrent stenosis developed at 16 months with one episode of transient ischemic attack.

CONCLUSION

Deployment of a self-expanding stent alone resulted in a favorable and more gradual reduction of severe symptomatic carotid stenosis. Improvements in stent profile and chronic outward force may widen the indications for simple stent placement without the use of balloons or adjunctive protection devices.