Abstract W MP70: Characteristics of Patients With Microemboli Detected With Transcranial Doppler Monitoring

Abstract

Introduction: TCD emboli monitoring (TCDe) is a non-invasive tool used to detect the presence of ongoing microembolic signals (MES) in the intracranial arterial vessels. The clinical utility of this test in the evaluation of acute stroke patients has been debated. Our goal was to evaluate clinical factors associated with MES in ischemic stroke patients who underwent TCDe to determine which patient population may benefit from TCDe. Methods: Retrospective cohort study of adult patients admitted to our tertiary care center for TIA or ischemic stroke from 2011 to 2012 who underwent TCDe. Monitoring was performed for 20 minutes using a standardized protocol. Inclusion criteria included insonatation of both middle cerebral arteries and completion of TCD bubble study (TCB). Repeat TCDe performed on the same patient were excluded from the analysis. Demographic, clinical and objective data were collected using our EMR system. Results: Of the 113 patients included in the final analysis, mean age was 57.9 years and 46.9% were female. MES occurred in 33.6% patients. Mean # of MES was 9.3 (SD 60.6). Patients with MES were significantly younger (51.8 years vs 61.0, p.006) and had fewer vascular risk factors: diabetes (10.5% vs 33.3%, p 0.006), hyperlipidemia (23.7% vs 49.3%, p 0.007), hypertension (47.4% vs 17.33%, p 0.067), atrial fibrillation (7.9% vs 17.33 %, p 0.16), congestive heart failure (5.3% vs 10.7%, p 0.32) and coronary artery disease (18.4 % vs 29.3%, p 0.2). Cryptogenic stroke and the presence of right to left shunt (RLS) was more frequent in patients with MES than those without. Mean WBC count and usCRP were both nonsignificantly higher in patients with MES. Conclusions: Clinical characteristics of patients with MES on TCDe differed from those without MES, which may have diagnostic and clinical implications. Patients with MES were younger and had fewer stroke risk factors. MES were seen more often in patients with RLS and in those with cryptogenic stroke, which raises the possibility of an association between these two factors. Interestingly, patients with MES also had higher usCRP and WBC values, suggesting a possible inflammatory component to the occurrence of MES. More research is needed with a larger sample size to better define the significance of the above findings.