Background and purpose: Carotid and Vertebral Artery Transluminal Angioplasty Study (CAVATAS) patients with carotid stenosis were randomized between endovascular treatment and endarterectomy. The rates of residual severe stenosis and restenosis and their contribution to recurrent symptoms was unclear.

Methods: Endovascular patients were treated by balloon angioplasty alone (88%) or stenting (22%). Patches were used in 63% of endarterectomy patients. Carotid stenosis was categorized as mild (0% to 49%), moderate (50% to 69%), severe (70% to 99%), or occluded, using standardized Doppler ultrasound criteria at the examination closest to 1 month (n=283) and 1 year (n=347) after treatment. Recurrent cerebrovascular symptoms during follow-up were analyzed.

Results: More patients had > or =70% stenosis of the ipsilateral carotid artery 1 year after endovascular treatment than after endarterectomy (18.5% versus 5.2%, P=0.0001). Residual severe stenosis was present in 6.5% of patients at 1 month after endovascular treatment. Between 1 month and 1 year, restenosis to > or =70% stenosis occurred in 10.5% of the endovascular group. After endarterectomy, 1.7% had residual severe stenosis at 1 month, and 2.5% developed severe restenosis. The results were significantly better after stenting compared with angioplasty alone at 1 month (P<0.001) but not at 1 year. Recurrent ipsilateral symptoms were more common in endovascular patients with severe stenosis (5/32 [15.6%]) compared with lesser degrees of stenosis at 1 year (11/141 [7.8%], P=0.02), but most were transient ischemic attacks and none were disabling or fatal strokes. There were no recurrent symptoms in the 9 endarterectomy patients with > or =70% stenosis at 1 year.

Conclusions: Carotid stenosis 1 year after endovascular treatment is partly explained by poor initial anatomical results and partly by restenosis. The majority of patients were treated by angioplasty without stenting. Further randomized studies are required to determine whether newer carotid stenting techniques are associated with a lower risk of restenosis. The low rate of recurrent stroke in both endovascular and endarterectomy patients suggests that treatment of restenosis should be limited to patients with recurrent symptoms, but long term follow up data are required.