TRANSCRANIAL DOPPLER-DETECTED MICROEMBOLI IN PATIENTS WITH ACUTE STROKE

Background and Purpose Transcranial Doppler sonography (TCD) has been used to detect microembolic signals in a variety of clinical situation s. We studied the prevalence of TCD-detected microemboli in 38 acute s troke patients. Methods Consecutive patients with acute anterior circu lation stroke were stratified into high-risk (group 1), medium-risk (g roup 2), and low-risk (group 3) groups based on their risk factors for cerebral embolism. Results Microemboli were detected in 11% of patien ts. They were present in 17% of group 1, 10% of group 2, and 0% of gro up 3 patients. Emboli were present in patients with mechanical prosthe tic valves, carotid stenosis (>70%), and mitral valve strands with a p atent foramen ovale. Patients with microemboli more frequently had a h istory of cerebral ischemia compared with patients without microemboli (P<.05). They also more frequently had recent (<3 months) symptoms co mpared with patients without microemboli (P<.05). In patients with a c ardiac source of embolization, the number of microemboli detected was directly proportional to the acuity of previous symptoms. Conclusions These data suggest that TCD-detected microemboli are associated with a n increased prevalence of prior cerebrovascular ischemia. The presence of TCD-detected microemboli could be a risk factor for cerebrovascula r ischemia.