Carotid angioplasty and stent placement: comparison of transcranial Doppler US data and clinical outcome with and without filtering cerebral protection devices in 509 patients.

PURPOSE: To prospectively evaluate emboli detected at transcranial Doppler ultrasonography (US) and outcome of carotid angioplasty and stent placement and compare these findings in patients treated with the use of filtering cerebral protection devices (CPDs) with the findings in patients treated without the use of filtering CPDs. MATERIALS AND METHODS: This study was approved by the institutional human research committee. Written informed consent was obtained for all patients. Patients were divided into three groups: 161 patients treated before filtering CPDs had become available (group 1), 151 patients treated with filtering CPDs (group 2), and 197 patients treated without CPDs after CPDs had become available (group 3). Clinical end points were cerebral ischemic events and death. Transcranial Doppler US end points included isolated microemboli, microembolic showers, macroemboli, and distal thrombus. The procedure was divided into five phases: wiring, predilation, stent deployment, postdilation, and CPD handling. Data not distributed normally were analyzed with the Mann-Whitney U statistic. For binomial data, the chi(2) test was used. P < .05 indicated statistical significance. RESULTS: For each phase, median and interquartile range (IQR) for isolated microemboli in group 2 versus group 3 were as follows: wiring, 51 (IQR, 31-69) versus 27 (IQR, 15-48); predilation, 19 (IQR, 13-33) versus 13 (IQR, 8-19); stent deployment, 64 (IQR, 46-82) versus 48.5 (IQR, 33.25-66); and postdilation, 24 (IQR, 14-39) versus 16 (IQR, 11-27.5) (P < .001 for each phase). Median and IQR for microembolic showers were as follows: wiring, 0 (IQR, 0-3) versus 0 (IQR, 0-0); predilation, 1.5 (IQR, 0-4) versus 0 (IQR, 0-2); stent deployment, 22 (IQR, 11-36) versus 11 (IQR, 6-17); postdilation, three (IQR, 0-9) versus one (IQR, 0-4); (postdilation phase, P = .001; all other phases, P < .001). Median for isolated microemboli in group 1 versus groups 2 and 3 combined were as follows: predilation, 10 (IQR, 5-22.75) versus 16 (IQR, 9-25) (P = .001); stent deployment, 32 (IQR, 15-58) versus 54 (IQR, 40.5-74) (P < .001); and postdilation, 11 (IQR, 6-19) versus 18 (IQR, 12-33) (P < .001). Median for microembolic showers during stent deployment were six (IQR, 1-14) versus 13 (IQR, 7-26) (P < .001). Five patients died, and five major strokes and 14 minor strokes occurred. Eight macroemboli occurred in unprotected procedures; six distal thrombi occurred in protected procedures. CONCLUSION: Carotid angioplasty and stent placement yielded more microemboli in patients treated with filtering CPDs than in unprotected procedures. The infrequent occurrence of cerebral sequelae did not allow comprehensive statistical comparison between groups.

New brain lesions at MR imaging after carotid angioplasty and stent placement.

PURPOSE: To assess, with magnetic resonance (MR) imaging, the number and size of new brain lesions after carotid angioplasty and stent placement (CAS) and to evaluate the association of these new lesions with neurologic deficits and transcranial Doppler ultrasonographic (US) data. MATERIALS AND METHODS: Seventy-two consecutive CAS procedures were performed in 72 patients. Patients underwent neurologic examination before, during, immediately after, and 1 day, 3 months, and 1 year after CAS. MR imaging was used before and after CAS to assess the number of symptomatic and silent new infarctions. Two radiologists reviewed all pre- and postintervention MR images. The radiologists were blinded to the clinical data. RESULTS: Postprocedural MR images showed new lesions on the side of stent placement in 11 patients. In six patients, the new lesions were clinically silent. Two patients had a major stroke, one had a minor stroke, and two had transient ischemic attack. In patients who had had transient ischemic attack or stroke before CAS, the frequency of new lesions at postprocedural MR imaging was higher (23%) than in asymptomatic patients (12%); this difference was not statistically significant (P =.29). There was no statistically significant correlation between embolic load as detected with transcranial Doppler US monitoring and the occurrence of either clinical symptoms or new lesions seen at MR imaging. CONCLUSION: CAS is associated with embolic events. The majority of new lesions seen on postintervention MR images are not detected at neurologic examination.