Silent cerebral ischemic lesions after carotid artery stenting with distal cerebral protection.

OBJECTIVE

To evaluate by MR diffusion weighted image (DWI-MR) the presence of new ischemic cerebral lesions after carotid artery stenting (CAS) and distal cerebral protection, in patients with internal carotid artery (ICA) stenosis >70.

METHODS

Sixty-seven CAS were performed under cerebral protection with a distal filter. Mean age of the patients was 68.3 years (range 37-86) and 42 patients (62.7%) were symptomatic. An EZ filter device was used in all cases. The mean length of the procedure was 22.2 minutes (range 8-110). All patients had a cerebral MRI done in the 3 days before CAS and a DW-MR (eco planar single shot, b=1000 mm2/seconds) was done the day after.

RESULTS

As a consequence of the CAS, three transient ischemic attacks were observed. There was one minor stroke (1.5%) on day 21, but no major stroke, death or myocardial infarction in a 30-day period. DW-MRI after CAS showed 26 new silent ischemic lesions in 11 asymptomatic patients (16.4%). In six, they were multiple (range 2-5). Lesions were mainly seen in the ipsilateral medial cerebral artery (21); four in the posterior fossa, and one in the contralateral medial cerebral artery.

DISCUSSION

Although the use of distal cerebral protection was safe, new cerebral ischemic lesions, supposedly embolic, were observed in 16.4% of the patients. Although without clinical consequences in our series, their moderate high incidence should promote the investigation of safer techniques and devices.