Study Population
24 consecutive patients post cardiac surgery who were referred to our
institution for AT ablation were enrolled prospectively between June
2018 and November 2019. All cases were performed under conscious
sedation with continuous intravenous fentanyl. All patients provided
written informed content to participate in the study, which was approved
by the institutional ethics committee.Electrophysiological Study
All antiarrhythmic drugs were discontinued for at least five half-lives,
except for amiodarone, which was stopped at least two weeks before the
procedure. Transesophageal echocardiography was performed to exclude the
presence of thrombus in left atrial appendage prior to the procedure.
Electrophysiology study was performed under conscious sedation and local
anesthesia. Twelve-lead surface electrocardiograms (ECG) (filtered
0.05-100Hz) and bipolar intracardiac electrograms (filtered 30-250Hz,
sweep speed 100 mm/second) were amplified and displayed on a
computer-based digital amplifier/recorder system (Bard
Electrophysiology, Lowell, MA, USA).
Following vascular access, a 6F quadripolar electrode was placed in the
right ventricular apex, and a 6F decapolar catheter was positioned in
the coronary sinus via the left femoral vein. One 8.5F long sheath was
advanced into the right atrium through the right femoral vein. A
transseptal puncture was performed in the patients with AT originating
from left atrium. Regular doses of heparin were administered to maintain
an activated clotting time of 300-350 seconds throughout the whole
procedure.