2.2 Ablation procedure and anticoagulation
The precise protocol for RFCA in our institution is published
elsewhere.6Pre-procedural anticoagulation was performed with either warfarin or
non-vitamin K oral anticoagulant (NOAC). Some patient was not prescribed
with anticoagulants. However, we performed transesophageal
echocardiography (TEE) in 92.9% of patients to rule out any thrombus or
sludge in left atrium (LA) of left atrial appendage (LAA). Emptying,
filling, and average flow velocity of the LAA were measured during TEE
evaluation. Protocols of our pre-procedural imaging evaluation are
published elsewhere.14Either computed tomography (CT) or magnetic resonance imaging (MRI)
study was performed to assess the anatomy of the pulmonary veins and to
create a three-dimensional reconstruction map using either EnSite NavX
or CARTO systems. During RFCA, intravenous heparin was administered to
maintain activated coagulation time between 300 – 350 seconds.
After index RFCA, anticoagulation with either warfarin or NOAC was
performed for at least two months after the procedure. After two months,
anticoagulation therapy was given to patients with
CHA2DS2-VASc score ≥ 2. Anticoagulation
was discontinued, at the operator’s discretion, if no AF was documented
on regular Holter monitoring (every 3 months for the first year and
every 6 months thereafter).