Objective: It has been reported that embolic signal (ES) detected by transcranial Doppler (TCD) has clinical significance, especially in patients with recent stroke attributable to arterial or cardiac embolism. Therefore, we conducted this study to determine whether the prevalence of ES is high in ischemic stroke patients with cancer and related to hypercoagulopathy.
Methods: We prospectively studied cancer patients with acute ischemic stroke within the middle cerebral artery (MCA) distribution on diffusion-weighted imaging. Conventional stroke mechanisms (CSMs) were determined using cardiologic and vascular studies. Additionally, the coagulation status was assessed based on the serum D-dimer levels, and TCD monitoring was performed on both MCAs for 30 minutes to detect ES. Clinical features including vascular risk factors, characteristics of ischemic stroke, and cancer and laboratory findings associated with the presence of ES were evaluated.
Results: A total of 74 patients were finally included in this study. ES was more commonly observed in patients without CSMs (22 of 38 patients, 57.9%) than in those with CSMs (12 of 36 patients, 33.3%) (p = 0.034). Moreover, ES was more commonly detected in patients with high D-dimer levels (p < 0.001), and D-dimer levels were significantly correlated with the number of ESs in patients without CSMs (r = 0.732, p < 0.001), but were poorly correlated in patients with CSMs (r = 0.152, p = 0.375). Higher levels of D-dimer (odds ratio [OR], 1.082 per 1 microg/ml increase; 95% confidence interval [CI], 1.014-1.154) and adenocarcinoma (OR, 3.829; 95% CI, 1.23-13.052) were independently associated with the presence of ES. The use of anticoagulants dramatically decreased the D-dimer levels.
Interpretation: A high prevalence of ES was observed in cancer patients with ischemic stroke, especially in those without CSMs. Elevated D-dimer levels were independently associated with ES, and decreased dramatically with the use of anticoagulants. ANN NEUROL 2010;68:213-219.