Non-vitamin K antagonist oral anticoagulants do not increase cerebral microbleeds
Non-vitamin K antagonist oral anticoagulants do not increase the likelihood of cerebral microbleeds in patients with non-valvular atrial fibrillation, according to study results published in the Journal of Stroke and Cerebrovascular Diseases.
“One of the most important findings of this study was the fact that no AF patients with non-vitamin K antagonist oral anticoagulants developed cerebral microbleeds in the space of a year,” the authors write.
Tsukasa Saito, MD, PhD, and colleagues at Asahikawa Medical University in Japan examined 69 patients, aged 45 and older, with AF. Patients with valvular AF were excluded.
Baseline brain MRIs were conducted for all patients and repeated at the conclusion of the 1-year study period to detect new-onset or changing cerebral microbleeds. Anticoagulation therapy to prevent cardiogenic embolism was continued for the duration of the study. The CHA2DS2-VASc score was also considered, according to the study results, as “some of its components also play a key role in focal cerebral microangiopathy.”
Among 69 patients with AF, novel cerebral microbleeds developed in 9 patients (13%). Six of these cerebral microbleeds were located within the lobes of the brain; 3 microbleeds were deep or infratentorial in location.
Twenty-three patients were taking non-vitamin K antagonist oral anticoagulants, including 1 each on apixaban 10 mg, apixaban 5 mg, or dabigatran 300 mg; 9 on rivaroxaban (5 on 15 mg and 4 on 10 mg); and 11 on dabigatran 220 mg. No cerebral microbleeds developed in these patients during the study period.
Twenty-one study participants were taking warfarin. According to the research, three of these patients developed novel cerebral microbleeds.
Non-vitamin K oral anticoagulants have come into widespread use for the prevention of cardiogenic embolism, as they compare equally to, or exceed, warfarin in terms of safety and efficacy, the study authors note.
Elements of the CHA2DS2-VASc score were not associated with novel cerebral microbleeds, study results demonstrate.
“Despite some pathophysiological mechanism of AF itself enhancing the vulnerability of cerebral small vessels, the AF patients with non-vitamin K oral anticoagulants did not develop cerebral microbleeds for 1 year in the present study,” the authors write. “It may be highly possible that non-vitamin K oral anticoagulants do not harm the cerebral small vessels and, therefore, can cause less cerebral microbleeds. Furthermore, the performance of non-vitamin K oral anticoagulants is independent of prior warfarin exposure.” – by Julia Ernst, MS
Disclosure: The authors report no relevant financial disclosures.