Abstract
Aims A multipolar pulsed-field ablation (PFA) catheter was
recently introduced for pulmonary vein isolation and shows great promise
with respect to procedural efficacy and safety. We describe our initial
experience using this multipolar PFA catheter for the treatment of left
atrial (LA) reentry tachycardia. Methods We included all
patients with LA reentry tachycardia treated with PFA at our institution
between September 2021 and March 2022. The tachycardia mechanism was
identified using 3D electro-anatomical mapping (3D-EAM). Subsequently, a
roof line, anterior line, or mitral isthmus line was ablated as
appropriate. Roof line ablation was always combined with LA posterior
wall (LAPW) isolation. Supplementary ablation of a roof- or anterior
line was added in patients with extensive low-voltage areas to avoid
future arrhythmias. Positioning of the PFA catheter was guided by a
3D-EAM system, and by fluoroscopy. Bidirectional block across lines was
verified using standard criteria. Additional focal radiofrequency
ablation (RFA) was used to achieve bidirectional block as necessary.
Results Among 22 patients (median age 70 (59-75) years; 9
females), we identified 27 LA reentry tachycardia: Seven roof dependent
macro-reentries, one micro-reentry located on the posterior wall, twelve
peri-mitral macro-reentries, and seven micro-reentries located on the
anterior wall. We ablated a total of 20 roof lines, 13 anterior lines
and 6 mitral isthmus lines. Additional RFA was necessary for two
anterior lines (15%) and three mitral isthmus lines (50%).
Bidirectional block was achieved across all roof lines, 92% of anterior
lines and 83% of mitral isthmus lines. We observed no acute procedural
complications. Conclusion Ablation of a roof line and LAPW
isolation is feasible, effective and safe using this multipolar PFA
catheter. However, the catheter is less suited for ablation of the
mitral isthmus and the anterior line. A focal pulsed-field ablation
catheter may be more effective for ablation of these lines.