Factors Associated with Silent Cerebral Events During Atrial
Fibrillation Ablation in Patients on Uninterrupted Oral Anticoagulation
Introduction: Silent cerebral events (SCEs) are related to the potential
thromboembolic risk in atrial fibrillation (AF) ablation.
Peri-procedural uninterrupted oral anticoagulation (OAC) reportedly
reduced the risk of SCEs, but the incidence still remains. Methods and
Results: AF patients undergoing catheter ablation were eligible. All
patients took non-vitamin K antagonist oral anticoagulants (NOACs,
n=248) or vitamin K antagonist (VKA, n=37) for peri-procedural OAC
(>4 weeks) without interruption during the procedure. Brain
magnetic resonance imaging was performed within 2 days after the
procedure to detect SCEs. Clinical characteristics and procedure-related
parameters were compared between patients with and without SCEs. SCEs
were detected in 66 patients (23.1%, SCE[+]) but were not detected
in 219 patients (SCE[-]). Average age was higher in SCE[+] than
in SCE[-] (66±10 years vs. 62±12 years, p<0.05).
Persistent AF prevalence, CHADS2/CHA2DS2-VASc scores, serum NT-ProBNP
levels, left-atrial dimension (LAD), and spontaneous echo contrast
prevalence in transesophageal echocardiography significantly increased
in SCE[+] vs. SCE[-]. SCE[+] had lower baseline activated
clotting time (ACT) before heparin injection and longer time to reach
optimal ACT (>300 sec) than SCE [-] (146±27 sec vs.
156±29 sec and 44±30 sec vs. 35±25 sec, p<0.05, respectively).
In multivariate analysis, LAD, baseline ACT, and time to reach the
optimal ACT were predictors for SCEs. The average values of the ACT
parameters were significantly different among NOACs/VKA. Conclusion: LAD
and intra-procedural ACT kinetics significantly affect SCEs during AF
ablation. Different anticoagulants have different impacts on ACT during
the procedure, which should be considered when estimating the risk of