Related Experiment Videos
Comparison of single-biphasic versus sequential-biphasic shocks on defibrillation threshold in pigs
Z Csanadi1, D L Jones, G K Wood
1Heart and Circulation Group, John P. Robarts Research Institute, London, Ontario, Canada.
Pacing and Clinical Electrophysiology : PACE
|June 1, 1997
Summary
Sequential-biphasic shocks, utilizing multiple pathways, demonstrated improved defibrillation efficacy compared to single-biphasic shocks. This novel approach requires lower energy for direct heart defibrillation.
Area of Science:
- Biomedical Engineering
- Cardiovascular Research
- Medical Devices
Background:
- Current implantable cardioverter defibrillators (ICDs) employ various shock waveforms, often truncating energy delivery.
- Optimizing defibrillation efficacy is crucial for patient outcomes and device performance.
Purpose of the Study:
- To investigate if a sequential-biphasic shock, utilizing multiple pathways, improves defibrillation efficacy compared to a standard single-biphasic shock.
- To compare energy requirements and shock parameters between the two waveform types.
Main Methods:
- A comparative study in eight anesthetized pigs using epicardial mesh electrodes.
- Testing of single-biphasic and sequential-biphasic shock waveforms delivered from a single capacitor bank.
- Randomized crossover design to obtain triplicate defibrillation threshold (DFT) measurements for each waveform.
Main Results:
- Sequential-biphasic shocks required significantly lower initial leading edge voltage, peak current, and delivered energy at the DFT compared to single-biphasic shocks.
- The sequential-biphasic waveform delivered remaining charge to two pathways, enhancing energy utilization.
Conclusions:
- Combining sequential capability with biphasic shocks and delivering charge to multiple pathways is a promising strategy for direct heart defibrillation.
- This approach may lead to more efficient and effective ICD therapy by reducing energy requirements.