Key result
A novel epicardial sock electrode significantly reduced skeletal muscle contraction force at internal defibrillation threshold compared to control (1.3 vs 10.6 kg, P<0.0001) in dogs.
Why the study?
Does a novel epicardial panel electrode system reduce shock-induced skeletal muscle force during internal defibrillation compared to standard transvenous coil/dummy can configuration in adult mongrel dogs?
Does a novel epicardial panel electrode system reduce shock-induced skeletal muscle force during internal defibrillation compared to standard transvenous coil/dummy can configuration in adult mongrel dogs?
Absolute Event Rate: 1.3% vs 10.6%
p-value: p=< 0.0001
A novel epicardial electrode system significantly reduces skeletal muscle contraction force during internal defibrillation while preserving external defibrillation capability when disconnected, suggesting a potential approach for painless ICD therapy.
Reduces shock-induced muscle force in dogs; leaves open translation to painless human ICD therapy.
BACKGROUND: Implantable cardioverter defibrillators (ICDs) save lives, but the defibrillation shocks delivered by these devices produce substantial pain, presumably due to skeletal muscle activation. In this study, we tested an electrode system composed of epicardial panels designed to shield skeletal muscles from internal defibrillation, but allow penetration of an external electric field to enable external defibrillation when required. METHODS AND RESULTS: Eleven adult mongrel dogs were studied under general anesthesia. Internal defibrillation threshold (DFT) and shock-induced skeletal muscle force at various biphasic shock strengths were compared between two electrode configurations: (1) a transvenous coil placed in the right ventricle (RV) as cathode and a dummy can placed subcutaneously in the left infraclavicular fossa as anode (control configuration) and (2) RV coil as cathode and the multielectrode epicardial sock with the panels connected together as anode (sock-connected). External DFT was also tested with these electrode configurations, as well as with the epicardial sock present, but with panels disconnected from each other (sock-disconnected). Internal DFT was higher with sock-connected than control (24 +/- 7 J vs. 16 +/- 6 J, P < 0.02), but muscle contraction force at DFT was greatly reduced (1.3 +/- 1.3 kg vs. 10.6 +/- 2.2 kg, P < 0.0001). External defibrillation was never successful, even at 360 J, with sock-connected, while always possible with sock-disconnected. CONCLUSION: Internal defibrillation with greatly reduced skeletal muscle stimulation can be achieved using a novel electrode system that also preserves the ability to externally defibrillate when required. This system may provide a means for painless ICD therapy.
No takes yet. Share an insight, caveat, or question.
Jayanti et al. (2007) studied Defibrillation (n=11). Epicardial sock electrode (sock-connected) vs. Transvenous RV coil and subcutaneous dummy can (control) was evaluated on Shock-induced skeletal muscle force at internal defibrillation threshold (p=< 0.0001). A novel epicardial sock electrode significantly reduced skeletal muscle contraction force at internal defibrillation threshold compared to control (1.3 vs 10.6 kg, P<0.0001) in dogs.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: