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What Do Anticoagulants Say about Microemboli?
Serkan Demir1, Mehmet F Ozdag1, Mustafa T Kendirli1
1Department of Neurology, GATA Haydarpaşa Training Hospital, Istanbul, Turkey.
Insights
This study found no significant difference in microembolic signals (MES) frequency among warfarin, rivaroxaban, and dabigatran treatments for atrial fibrillation (AF) patients. MES screening can help assess stroke risk during anticoagulant therapy.
Area of Science:
- Neurology
- Cardiology
- Vascular Medicine
Background:
- Atrial fibrillation (AF) increases stroke risk.
- Anticoagulant therapy is crucial for managing AF-related stroke risk.
- Microembolic signals (MES) detected by transcranial Doppler ultrasound (TCD) may indicate embolic events.
Purpose of the Study:
- To evaluate and compare the frequency of microembolic signals (MES) in patients with nonvalvular atrial fibrillation (AF) undergoing treatment with warfarin, rivaroxaban, or dabigatran.
- To assess the utility of MES screening in predicting stroke risk in AF patients on anticoagulant therapy.
Main Methods:
- A total of 215 patients with nonvalvular AF and a history of stroke were included.
- Patients were treated with warfarin (46%), rivaroxaban (31%), or dabigatran (23%).
- Microembolic signals (MES) were monitored bilaterally using transcranial Doppler (TCD) for 30 minutes; CHA2DS2VASc scores and INR (for warfarin) were recorded.
Main Results:
- The incidence of emboli was 32% for warfarin, 36% for rivaroxaban, and 35% for dabigatran.
- No statistically significant differences in MES frequency were observed between the anticoagulant treatment groups.
- A positive correlation between CHA2DS2VASc scores and MES, and a negative correlation between INR and MES in the warfarin group were noted.
Conclusions:
- Anticoagulant therapy for AF does not significantly alter MES frequency across different drug classes.
- MES screening using TCD can serve as a valuable tool for assessing individual stroke risk in AF patients.
- Further research may refine the role of MES monitoring in optimizing anticoagulant strategies for stroke prevention.
Background:
In this study, we evaluated the microembolic signals (MES) frequency with transcranial Doppler ultrasound (TCD) in patients with atrial fibrillation (AF) under anticoagulant therapy, and we compared the treatment groups.
Methods:
Ninety-nine patients with nonvalvular AF with a history of stroke using warfarin (46%), 67 patients using rivaroxaban (31%), and 49 patients using dabigatran (23%), that is, a total of 215 patients, who have been referred to the stroke outpatient section of our department from May 2013 to November 2014, were included in the study. CHA(2)DS(2)VASc scoring was made for all patients, and International Normalized Ratio (INR) value was evaluated in patients using warfarin. All patients were monitored with TCD on the middle cerebral arteries bilaterally for 30 minutes. Embolic signals were evaluated according to their density and the mean number of signals in 2 consecutive recordings.
Results:
The incidence of emboli in the treatment group was 32 (32%) for warfarin, 24 (36%) for rivaroxaban, and 17 (35%) for dabigatran. The analysis of variance revealed that there was no statistically significant differences between the treatment groups in terms of patients' age (P = .145), CHA(2)DS(2)VASc scores (P = .968), and the number of emboli (P = .783). As CHA(2)DS(2)VASc score increases, number of emboli increase. A statistically significant negative correlation between the number of emboli and INR scores was found in the warfarin group. The number of emboli decreases as INR decreases.
Conclusions:
As we aim to reduce the risk of emboli to a minimum with anticoagulant therapy, this screening for MES can give us an idea for the risk of stroke.
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