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Updated: Apr 26, 2026
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High-Resolution Endocardial and Epicardial Optical Mapping in a Sheep Model of Stretch-Induced Atrial Fibrillation
Published on: July 29, 2011
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Parasystole in a mahaim accessory pathway
Roopa Tekkatte1, Ahmed Hamoud2, Claire Warren2
1Cardiff and Vale University Health Board, United Kingdom.
Indian Pacing and Electrophysiology Journal
|July 25, 2014
Summary
Subcutaneous implantable cardioverter-defibrillators (S-ICDs) offer an alternative for hypertrophic cardiomyopathy (HCM) patients at high risk of sudden cardiac death. However, this case highlights potential challenges with S-ICD lead placement and sensing in HCM.
Area of Science:
- Cardiology
- Electrophysiology
- Medical Devices
Background:
- Hypertrophic cardiomyopathy (HCM) is a significant risk factor for sudden cardiac death (SCD).
- Implantable Cardioverter-Defibrillators (ICDs) are used for primary and secondary prevention of SCD in HCM.
- Subcutaneous ICDs (S-ICDs) provide a leadless alternative to transvenous ICDs.
Purpose of the Study:
- To report the use of S-ICD in a patient with HCM and multiple SCD risk factors.
- To describe complications encountered with S-ICD therapy in this specific patient population.
Main Methods:
- Case report detailing the implantation and subsequent management of an S-ICD in a patient with HCM.
- Analysis of device performance, including sensing parameters and shock delivery.
Main Results:
- The S-ICD required extraction due to recurrent inappropriate shocks.
- Inappropriate shocks were attributed to oversensing of atrial flutter.
- The S-ICD failed to treat a ventricular tachycardia (VT) episode.
Conclusions:
- This case highlights a potential limitation of S-ICD therapy in HCM patients related to oversensing.
- Atrial flutter oversensing causing inappropriate shocks with S-ICD has not been previously reported.
- Further investigation into S-ICD sensing characteristics in HCM patients is warranted.
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