Patients with subclinical atrial fibrillation (AF) are at a higher-than-average risk of having a stroke, although lower than with clinical AF. Now, results from a new trial suggest that the drug apixaban could help to lower this risk.
Eliquis (Apixaban) Credit: Pfizer
Subclinical AF, also known as atrial heart rhythm episodes (AHRE), is a type of atrial fibrillation that occurs without symptoms. It is short-lasting and usually only detected with the aid of implantable devices, such as pacemakers or defibrillators.
Read Also: Standard Treatment For Adults With Severe Stroke Also Helpful For Children
Researchers found in the Apixaban for the Reduction of Thrombo-Embolism in Patients with Device-Detected Subclinical Atrial Fibrillation (ARTESIA) trial, which was reported in The New England Journal of Medicine (NEJM), that apixaban lowered stroke risk better than aspirin. However, this benefit came with an amplified risk of major bleeding among subclinical AF patients.
Apixaban AKA Eliquis is an anticoagulant that is used to prevent or correct blood clots. It is commonly used to prevent stroke in patients with nonvalvular atrial fibrillation.
Reduced stroke risk
Previously, researchers observed subclinical AF in more than a third of elderly people with hypertension who used a pacemaker. They linked the short-lasting episodes of atrial fibrillation with more than a two-fold risk of stroke or systemic embolism.
It was unclear what benefit oral anticoagulation would offer to people with subclinical AF. This was mainly because the use of oral anticoagulants is known to increase the risk of bleeding, especially among older patients.
Read Also: Danish Study Reveals Link Between Migraines and Elevated Stroke Risk in Women
With the ARTESIA trial, researchers wanted to find out whether apixaban would lower stroke risk better than aspirin.
The team enrolled 4,012 patients with subclinical AF that lasted between six minutes and 24 hours for the double-blind trial. The subjects were randomly assigned to receive a 5mg (or 2.5mg) dose of apixaban twice daily or an 81mg aspirin dose daily.
Following a mean follow-up duration of 3.5 years, 55 of the patients who received apixaban had a stroke compared to 86 in the aspirin group. Those numbers translated to primary efficacy outcomes of 0.78%/patient-year and 1.24%/patient-year respectively.
Higher risk of bleeding
While the oral anticoagulant lowered the risk of stroke, compared to aspirin, it led to a greater risk of major bleeding. This risk was calculated to be 1.71%/patient-year in the apixaban group and 0.4%/patient-year in the aspirin group.
Five patients receiving apixaban suffered fatal bleeding while eight of those who got aspirin experienced the same.
Read Also: Revolutionary Nasal Spray Could be the Key to Repairing Brain Damage from Strokes!
This study thus helps to show that apixaban (or oral anticoagulation) can help prevent stroke in some patients with subclinical AF. However, the big question is whether this is worth the increased risk of major bleeding linked to it.
There is an obvious need for further research on how the benefits and risks of oral anticoagulation can be balanced. This, for example, may require assessments in individual patients. Researchers believe some patient groups could find the treatment helpful.
Results from the ARTESIA trial conflict somewhat with those from the Non–Vitamin K Antagonist Oral Anticoagulants in Patients with Atrial High Rate Episodes (NOAH-AFNET 6) trial. The other study failed to show reduced stroke risk with the anticoagulant edoxaban. However, the NOAH-AFNET 6 trial was stopped rather too soon and included deaths caused by cardiovascular disease, among other issues.
References
Healey JS, Lopes RD, Granger CB, et al. (2023). Apixaban for Stroke Prevention in Subclinical Atrial Fibrillation. New England Journal of Medicine. https://doi.org/10.1056/NEJMoa2310234
FEEDBACK:
