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Updated: Aug 19, 2026

A New Single Chamber Implantable Defibrillator with Atrial Sensing: A Practical Demonstration of Sensing and Ease of Implantation
Published on: February 28, 2012
[Complex implantation of an automatic defibrillator-cardioverter through a left superior vena cava]
M Castaño Ruiz1, J Albertos Salvador, M Ruiz Fernández
1Servicio de Cirugía Cardiovascular, Hospital General Universitario Gregorio Marañón, Madrid.
Insights
A young patient with complex congenital heart disease experienced inappropriate defibrillator shocks due to myopotential oversensing. Lead repositioning and epicardial lead insertion resolved the issue, optimizing device function.
Area of Science:
- Cardiology
- Electrophysiology
- Congenital Heart Disease
Background:
- A 19-year-old female presented with a rare anatomical variation, a left superior vena cava, and a history of surgically corrected complete atrioventricular canal defect.
- Following an in-hospital sudden cardiac arrest, an automatic defibrillator-cardioverter was implanted via the left superior vena cava.
Observation:
- The patient experienced multiple inappropriate defibrillator discharges during the postoperative period.
- These events were attributed to myopotential oversensing, a known complication in patients with implanted cardiac devices.
Findings:
- Initial lead repositioning did not fully resolve the oversensing issue.
- A subsequent left submammarian thoracotomy allowed for the insertion of two epicardial leads, which ultimately provided an optimal result.
Implications:
- This case highlights the challenges in managing cardiac implantable electronic devices in patients with complex congenital heart anomalies.
- Successful management required a tailored approach involving lead revision and alternative lead placement strategies.
- Epicardial lead implantation can be an effective solution for device-related oversensing issues in select patient populations.
Abstract:
We describe the case of a 19-year-old girl with a left superior vena cava and a surgically corrected complete atrioventricular canal defect. After an inhospital sudden death an automatic defibrillator-cardioverter was implanted through her left superior vena cava. During the postoperative course, multiple inappropriate discharges caused by myopotential oversensing indicated the relocation of the electrode and, finally, insertion of two epicardial leads by a left submammarian thoracotomy approach, produced an optimal result.
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