Dynamic voltage threshold adjusted substrate modification technique for complex atypical atrial flutters with varying...

Area of Science:

• Electrophysiology
• Cardiac Surgery
• Cardiology

Background:

• Atypical atrial flutter (AFL) frequently occurs in patients with postsurgical atrial scars.
• Scar channels facilitate reentry, leading to variable flutter circuits and challenging ablation.
• Heterogeneous scarring contributes to AFL complexity and common recurrences.

Purpose of the Study:

• To test the hypothesis that dynamic voltage threshold adjustment can identify heterogeneous atrial scarring.
• To evaluate scar homogenization as a method to eliminate atypical AFLs.
• To assess the efficacy of this strategy in complex, scar-mediated AFL cases.

Main Methods:

• Studied patients undergoing atypical AFL ablation with a history of atriotomy and multiple flutter circuits.
• Excluded patients with stable, localizable flutter circuits.
• Performed high-density voltage mapping with adjusted thresholds to identify scar heterogeneity and channels.
• Utilized irrigated smart-touch ablation for scar homogenization.
• Assessed tachycardia re-inducibility and short-term/long-term outcomes.

Main Results:

• Five patients with prior surgery and multiple varying AFL morphologies were studied.
• Following scar homogenization, tachycardia was not inducible in any patient.
• No AFL recurrence was observed during a mean follow-up of 450 days.

Conclusions:

• High-density voltage mapping combined with scar homogenization is effective for complex, scar-mediated atypical AFL.
• This strategy successfully eliminates atypical AFL with multiple circuits.
• The approach offers a promising solution for challenging AFL cases post-atrial surgery.