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Benefits of Cardiac Resynchronization Therapy in an Asynchronous Heart Failure Model Induced by Left Bundle Branch Ablation and Rapid Pacing
Published on: December 11, 2017
Defibrillation energy requirements in an ICD population receiving cardiac resynchronization therapy
Claudio Schuger1, Kenneth A Ellenbogen, Mitchell Faddis
1Henry Ford Hospital, Detroit, Michigan, USA. cschuge1@hfhs.org
Journal of Cardiovascular Electrophysiology
|April 29, 2006
Summary
Defibrillation energy requirements (DERs) in cardiac resynchronization therapy with defibrillation capability (CRT-D) patients were characterized. While testing is generally safe, safety margins were not always achieved, with left ventricular internal dimension and procedure time predicting higher DERs.
Area of Science:
- Cardiology
- Electrophysiology
- Medical Devices
Background:
- Defibrillation energy requirements (DERs) are well-studied in conventional defibrillator patients.
- DERs in patients with cardiac resynchronization therapy with defibrillation capability (CRT-D) devices are not well-described.
Purpose of the Study:
- To characterize DERs in CRT-D patients.
- To compare CRT-D DERs with those of conventional defibrillator patients.
Main Methods:
- Retrospective analysis of the VENTAK CHF/CONTAK CD biventricular pacing study.
- Verification of safety margins (≥10 J) with successful conversions ≤21 J.
- Multivariate logistic regression to identify predictors of failed DER testing.
Main Results:
- Successful DER testing in 89% of 501 CRT-D patients.
- Larger left ventricular internal dimension and prolonged procedure time predicted higher energy requirements.
- DER testing was associated with few complications.
Conclusions:
- DER testing is safe and successful for most CRT-D patients.
- Safety margins could not be ascertained in a significant number of patients.
- Left ventricular internal dimension and procedure time may predict higher DERs, informing device selection.
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