Pulsed-field ablation for refractory typical atrial flutter resistant to multiple radiofrequency ablations: A...

Area of Science:

• Cardiology
• Electrophysiology
• Medical Technology

Background:

• Recurrent typical atrial flutter often necessitates repeat ablation procedures.
• Radiofrequency (RF) ablation targeting the cavotricuspid isthmus (CTI) can fail to achieve durable block, leading to persistent arrhythmia.
• Patients with multiple prior RF ablations present a challenge due to scarred atrial substrate.

Purpose of the Study:

• To evaluate the efficacy and safety of pulsed-field ablation (PFA) in a patient with longstanding, recurrent typical atrial flutter refractory to multiple RF ablations.
• To demonstrate the use of PFA in achieving durable CTI block in a complex patient scenario.
• To assess the long-term outcome of PFA for CTI-dependent atrial flutter.

Main Methods:

• Electrophysiological mapping to identify residual CTI conduction in a patient with a history of four prior RF ablations.
• Pulsed-field ablation (PFA) using a pentaspline catheter targeting the CTI.
• High-density voltage remapping post-PFA to confirm durable electrical block.
• 1-year clinical follow-up without antiarrhythmic therapy.

Main Results:

• Successful elimination of residual fragmented atrial electrograms across the CTI with PFA.
• Durable bidirectional CTI block confirmed by post-ablation remapping.
• No inducible arrhythmia post-procedure and arrhythmia-free status at 1-year follow-up.
• The procedure was complication-free, with no phrenic nerve injury or other adverse effects.

Conclusions:

• Pulsed-field ablation (PFA) is a viable and safe alternative for treating recurrent CTI-dependent atrial flutter in patients who have failed multiple conventional RF ablations.
• PFA can achieve durable electrical block across the CTI, even in complex, previously ablated substrates.
• Further prospective studies are needed to confirm these findings and establish long-term outcomes for PFA in this patient population.