Microembolic signal detection in patients with atrial fibrillation treated with oral anticoagulant

BACKGROUND: Atrial fibrillation (AF) is a well-known risk factor for embolic stroke. The incidence of stroke in patients with AF is 4.5% per year. In 93% of cases, strokes in patients with AF are of embolic origin. Trans Cranial Doppler (TCD) monitoring of silent micro-embolic signals (MES) can represent an effective preclinical tool for verifying the efficacy of embolic events in patients treated with antithrombotic prophylaxis (antiplatelet agents, Vitamin K inhibitors, and new oral anticoagulants direct thrombin inhibitors). METHODS: We enrolled 16 patients, of both sexes equally distributed (M = 8 plus F = 8) with a known diagnosis of AF with Ejection Fraction greater of 40%, all in anticoagulant treatment by direct oral anticoagulants (DOACs) and we assessed, through the use of a portable TCD-X, the MES signals during physical activity of 1 h. The aim was of evaluating whether the physical activity of a subject affected by AF worsens the incidence of MES in these subjects. Result: 25% of patients presented a MES at the time of registration. Two female of 38 and 75 year-old; and two male of 70 and 71 year-old. The 75-year-old woman reported an episode of instability while walking; therefore it was increased her anticoagulant treatment. Men did not perceive the MES. CONCLUSION: Both sexes reported the presence of MES equally with a prevalence of 25%. By correlating these results with those of the literature, it is deduced that physical activity is, therefore, not a risk factor for these patients being treated with DOACs. The TDC-X registration implemented is relatively short compared to the current potential of the device which is over 6 h; therefore, it is desirable that further studies be performed in future on statistically adequate sample cohorts and simultaneous bilateral recordings of MES.