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2: 1 AV block post ASD device closure - What is the mechanism
Sanjeev S Mukherjee1, Ashesh Halder2, Anil Kumar Singhi2
1AIIMS Kalyani, West Bengal, India.
Indian Pacing and Electrophysiology Journal
|June 14, 2025
Summary
Atrioventricular (AV) block can occur after atrial septal defect (ASD) device closure. Varying PR intervals in conducted beats may indicate compensation, not necessarily complete heart block (CHB).
Area of Science:
- Cardiology
- Electrophysiology
- Medical Devices
Background:
- Percutaneous closure of atrial septal defects (ASD) is a common procedure.
- Atrioventricular (AV) block is a potential complication following cardiac interventions.
- Understanding ECG findings post-intervention is crucial for patient management.
Purpose of the Study:
- To report a case of AV block after successful percutaneous ASD device closure.
- To investigate the significance of varying PR intervals in conducted beats.
- To differentiate between Wenckebach phenomenon and complete heart block (CHB) in this context.
Main Methods:
- Case report of a patient undergoing percutaneous ASD device closure.
- Electrocardiogram (ECG) analysis to assess cardiac rhythm and conduction.
- Literature review on AV block and Wenckebach phenomenon post-ASD closure.
Main Results:
- The patient developed 2:1 AV block after successful ASD device closure.
- ECG revealed varying PR intervals in conducted beats, mimicking CHB.
- Literature review suggests this pattern can be a compensatory mechanism in Wenckebach phenomenon.
Conclusions:
- Varying PR intervals in conducted beats post-ASD closure can represent a Wenckebach phenomenon.
- This finding necessitates careful ECG interpretation to avoid misdiagnosis of CHB.
- Management should focus on understanding the underlying electrophysiological compensation mechanisms.
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