by Will Boggs, MD
The risk of postprocedural cerebral microembolic events is lower after carotid endarterectomy (CEA) than after carotid angioplasty and stenting (CAS), according to a report in the August issue of the
Journal of Vascular Surgery."While we don't know the long term significance of these microemboli, they occur much more frequently in the carotid stent patient than in the endarterectomy patient," Dr. Jason T. Lee told Reuters Health. "This risk needs to be considered when offering patients CEA versus CAS."
Dr. Lee, from Stanford University Medical Center in California, and his associates used diffusion-weighted MRI to identify microembolic events in the 48 hours following CEA and CAS. Their goals were to determine whether either approach conferred relative protection against periprocedural microembolic events and to determine whether any specific factors influenced the risk of these events.
Nineteen of 27 CAS patients (70 per cent) showed evidence of acute postoperative cerebral microemboli, the authors report, compared with none of 19 patients who underwent CEA.
In the CAS group, nine microemboli were ipsilateral, seven were bilateral, and three were contralateral to the index carotid lesion.
Periprocedural neurologic sequelae developed in three CAS patients and no CEA patients, the investigators say, but all such sequelae resolved within 36 hours.
"The high number of microemboli during carotid stenting, while not really leading to demonstrable neurologic events, is concerning in that we don't know the long-term effects of small microemboli," Dr. Lee commented. "Certainly there are several procedural steps along the way that would intuitively lead to microemboli, such as accessing the aortic arch, crossing the lesion, ballooning, and stent placement. I believe these findings suggest we still need to be seeking out improvements in the stent technology."
The investigators' report indicates that the only factor associated with the development of microemboli in the CAS patients was the use of a diagnostic arch angiogram. "We now perform preoperative MRI/A or CT-A on patients we are considering for carotid stent intervention, which helps us to determine the arch classification and allows us to skip the step of performing an arch angiogram," Dr. Lee said.
"We do favor CEA when possible," Dr. Lee added. "At our institution, the stroke rate for CEA over the past 15 years is less than one per cent, therefore making it a very durable and safe procedure. Patients stay overnight only, and are discharged with minimal discomfort. They are typically back to routine activities relatively quickly."
Source: Reuters
