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Atrial Arrhythmia Following Extra-cardiac Fontan Surgery: Is the Arrhythmia Mechanism Characterized?
Sachin Nayyar1, Kasun De Silva2, Lee Benson3
1Department of Cardiology, Toronto General Hospital, University of Toronto, Toronto, Ontario, Canada; Department of Cardiology, Gold Coast University Hospital, Gold Coast, Australia.
Cardiac Electrophysiology Clinics
|August 11, 2026
Summary
This study presents a complex case of symptomatic atrial arrhythmia in a patient with a history of Fontan surgery and MAZE procedure. Innovative mapping techniques were required due to unique anatomical challenges and variable arrhythmia cycle lengths.
Area of Science:
- Cardiology
- Cardiac Electrophysiology
- Congenital Heart Disease
Background:
- A 31-year-old male presented with symptomatic atrial arrhythmia.
- The patient had a history of extra-cardiac Fontan surgery and MAZE procedure.
- Peculiar cardiac anatomy presented challenges for treatment access.
Purpose of the Study:
- To describe a challenging case of atrial arrhythmia management.
- To highlight the need for innovative electrophysiological mapping strategies.
- To discuss the electro-morphology of arrhythmia in a complex cardiac patient.
Main Methods:
- Percutaneous atrial access was achieved via perforation through the extra-cardiac tunnel.
- Innovative mapping techniques were employed to address changing tachycardia cycle lengths.
- Electrophysiological study and mapping were performed to characterize the arrhythmia.
Main Results:
- Successful characterization of the arrhythmia's electro-morphology was achieved.
- The study details the anatomical limitations encountered during the procedure.
- Variable tachycardia cycle lengths posed a mapping challenge.
Conclusions:
- Complex atrial arrhythmias can occur in patients with Fontan and MAZE history.
- Innovative mapping is crucial for managing arrhythmias in patients with unique anatomy.
- This case underscores the importance of tailored electrophysiological approaches.
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