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A New Single Chamber Implantable Defibrillator with Atrial Sensing: A Practical Demonstration of Sensing and Ease of Implantation
Published on: February 28, 2012
Inappropriate ICD shocks for inappropriate reasons.
Rakesh K Pai1, Moeen Abedin, David A Rawling
1Department of Internal Medicine, Cardiology Section, University of Utah Health Sciences Center, Salt Lake City, UT USA. rpai@renoheart.com
Indian Pacing and Electrophysiology Journal
|February 14, 2008
Summary
Inappropriate implantable cardioverter-defibrillator (ICD) shocks can be caused by electromagnetic interference (EMI) and lead terminal reversal. Identifying these unusual causes is crucial for correcting the ICD shock problem.
Area of Science:
- Cardiology
- Biomedical Engineering
- Electrophysiology
Background:
- Implantable cardioverter-defibrillators (ICDs) are critical for managing life-threatening arrhythmias.
- Inappropriate ICD shocks, delivering unnecessary therapy, can stem from various causes.
- Accurate diagnosis of shock etiology is vital for patient management and device optimization.
Purpose of the Study:
- To highlight two uncommon etiologies of inappropriate ICD shocks.
- To emphasize the role of electromagnetic interference (EMI) in triggering shocks.
- To report on lead terminal reversal as a cause of device malfunction.
Main Methods:
- Case report presentation of two patients experiencing inappropriate ICD shocks.
- Analysis of device diagnostics to identify the underlying cause of shocks.
- Review of lead integrity and electromagnetic compatibility.
Main Results:
- Both patients experienced inappropriate ICD shocks attributed to external electromagnetic interference (EMI).
- A subsequent finding revealed reversal of the proximal and distal DF-1 lead terminals in both cases.
- Correction of lead terminal orientation resolved the inappropriate shocks.
Conclusions:
- Electromagnetic interference (EMI) can mimic cardiac signals, leading to inappropriate ICD shocks.
- Reversal of ICD lead terminals is an unusual but significant cause of device malfunction.
- Thorough investigation of device function and lead integrity is essential when managing inappropriate ICD shocks.
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