DrugLib.com — Drug Information Portal

Rx drug information, pharmaceutical research, clinical trials, news, and more

Clopidogrel versus dipyridamole in addition to aspirin in reducing embolization detected with ambulatory transcranial Doppler: a randomized trial.

Author(s): King A, Bath PM, Markus HS

Affiliation(s): Clinical Neuroscience, St. George's University of London, Cranmer Terrace, London SW17 0RE, UK.

Publication date & source: 2011-03, Stroke., 42(3):650-5. Epub 2011 Jan 21.

Publication type: Comparative Study; Randomized Controlled Trial; Research Support, Non-U.S. Gov't

BACKGROUND AND PURPOSE: After stroke and transient ischemic attack there is a high early risk of recurrent stroke, particularly in large artery disease. It has been suggested more intensive antiplatelet regimens are required, but trial data are lacking. Treatment efficacy can be evaluated using transcranial Doppler detection of embolic signals. Ambulatory transcranial Doppler has recently been developed; prolonged recording may reduce subject numbers required to determine therapeutic efficacy. In a randomized trial (ISRCTN68019845) with blinded end point evaluation, we determined whether treatment with dipyridamole or clopidogrel, in addition to aspirin, was more effective at reducing embolization. METHODS: Consecutive patients with recent symptomatic carotid stenosis were recruited. Ambulatory transcranial Doppler and platelet aggregometry were performed at baseline and 48 hours. Patients, all on aspirin, were randomized to dipyridamole or clopidogrel. Recordings were analyzed offline masked to subject identity. RESULTS: Sixty patients were recruited, 30 in each arm. The primary end point of change in embolic signal frequency did not differ between groups (P=0.36). In patients with embolic signals at baseline, there was no difference in reduction in embolic signal frequency: dipyridamole (75.5; SD 17.7%) versus clopidogrel (77.5; SD 20.5%; P=0.77). Baseline platelet aggregation was not different between regimens, but at 48 hours, adenosine 5'-diphosphate aggregation rate (but not collagen) was lower with clopidogrel (P<0.001). CONCLUSIONS: Both dipyridamole and clopidogrel reduced embolization to a similar extent. Embolic signals are strong predictors of future stroke rate in this patient group. Our results suggest these 2 treatment regimens have similar efficacy in early secondary prevention of stroke, although this now needs testing in large Phase III trials.

Page last updated: 2011-12-09

-- advertisement -- The American Red Cross
Home | About Us | Contact Us | Site usage policy | Privacy policy

All Rights reserved - Copyright DrugLib.com, 2006-2017