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: 1,61 Patients treated before filtering CPDs had become available (group 1), 1.51 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 wiring, predilation stent, deployment, postdilation, and CPD handling Data not distributed normally were analysed 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 filtering CPDs than, in unprotected procedures The infrequent patients treated with occurrence of cerebral sequelae did not allow comprehensive statistical, comparison, between groups.