Comparison of Microembolism Detected by Transcranial Doppler and Neuropsychological Sequelae of Carotid Surgery and Percutaneous Transluminal Angioplasty

Abstract

Background and Purpose —Percutaneous transluminal angioplasty (PTA) is currently being assessed for the treatment of carotid stenosis. In comparison with carotid endarterectomy (CEA), there is evidence of an increased risk of cerebral microembolism during the procedure. We have sought evidence of any neuropsychological sequelae of carotid PTA and compared it with CEA to demonstrate the relative safety of the 2 treatment options. Methods —The neuropsychological outcomes after CEA and PTA were compared in 2 matched groups of patients with severe symptomatic carotid stenosis, 96% of whom had been randomized in the Carotid and Vertebral Artery Transluminal Angioplasty Study (CAVATAS), at a single center. Transcranial Doppler insonation of the middle cerebral artery was used to measure cerebral reactivity in response to carbon dioxide inhalation before treatment and then to detect microembolization of the ipsilateral cerebral hemisphere and measure changes in blood flow velocity during the procedures. The performance on a neuropsychological test battery administered before, 6 weeks after, and 6 months after the procedure was compared in 20 patients undergoing PTA and 26 having CEA. Results —At 6 weeks, 5 patients in each group showed a similar decline in neuropsychological performance; global measures showed no significant difference between the 2 procedures, despite a significantly higher incidence of microemboli during PTA. Both groups showed a marked reduction in anxiety after treatment. Conclusions —The findings provide some reassurance that PTA is not associated with greater cerebral complications than CEA, despite the higher embolic load recorded by transcranial Doppler ultrasonography during angioplasty.