First Clinical Experience With Reversible Electroporation Mapping in Atrial Flutter.

Area of Science:

• Cardiology
• Electrophysiology
• Medical Devices

Background:

• Reversible pulsed field ablation (PF_REV) temporarily blocks cardiomyocyte conduction, aiding in identifying critical ablation targets.
• Local capture by PF_REV may influence tachycardia mechanisms, necessitating characterization of its responses.

Purpose of the Study:

• To characterize the responses of nontriggered PF_REV pulses.
• To evaluate PF_REV as a novel clinical mapping tool for reentrant atrial flutter.

Main Methods:

• PF_REV pulses were delivered using a 9-mm lattice-tip catheter in 30 reentrant atrial tachycardias (26 patients).
• Local capture and responses to PF_REV pulses were assessed both inside and outside the tachycardia circuit.

Main Results:

• 34.4% of PF_REV pulses resulted in atrial capture and propagation, with longer coupling intervals for propagated pulses.
• Tachycardia termination or cycle length prolongation occurred only when PF_REV was delivered within the reentry circuit, demonstrating high specificity for critical isthmus identification.
• Reproducibility of PF_REV responses was high (82.9%).

Conclusions:

• PF_REV mapping is a feasible and reproducible tool for identifying critical sites in reentrant atrial tachycardia.
• The technique shows promise for guiding ablation, particularly in cases with narrow isthmuses.
• Optimization of triggering and dose titration may further enhance PF_REV mapping efficacy.