Catheter ablation procedure
In the present study,patients underwent left atrial and pulmonary
venous computed tomography angiography or transesophageal
echocardiography prior to CA to rule out thrombosis.
The strategy of CA for AF in our
center has been described before21. In brief, after
atrial septal puncture, a 3.5mm tip ablation catheter was used to
reconstruct the left atrial geometry under the guidance of the CARTO
system. In patients with paroxysmal AF, pulmonary vein isolation (PVI)
was performed with the endpoint of electrical isolation. In addition,
patients with recordings of typical atrial flutter underwent tricuspid
isthmus ablation. In patients with persistent AF, linear ablation
(mitral isthmus line, left atrial roof line and cavotricuspid isthmus
line) was performed in addition to PVI, with the endpoint of
bidirectional block across each of the 3 ablation lines as described
previously. If the sinus rhythm (SR) was not reached after the ablation
procedure, cardioversion was performed. For the repeated procedure, in
brief, the pulmonary veins (PVs) were checked to assess the PV
reconduction, and PVI was achieved by the gap ablation.
Moreover, if necessary, additional
ablation was performed (such as complex fractionated atrial
electrograms, superior vena cava) at the discretion of the operator.
Continuous infusion of heparin during the ablation was used to maintain
the activated clotting time (ACT) of 300-400 seconds. We monitored every
30 minutes throughout the ablation procedure to maintain the target ACT.