A new braided epicardial carbon electrode significantly decreased mean defibrillation threshold energy by 39% to 56% compared with a standard titanium patch (P<=0.05).
RCT (n=8)
Randomized order of testing
Does a tubular epicardial braided carbon electrode reduce defibrillation threshold energy compared to a standard titanium patch in a canine model?
A new braided epicardial carbon electrode significantly decreases defibrillation energy requirements compared to a standard titanium patch in a canine model.
Effect estimate: 39% to 56% decrease
p-value: p=<=0.05
BACKGROUND: Recent studies show that depending on the type of shock morphology used, 5% to 15% of patients requiring implantable defibrillators cannot be treated with a nonthoracotomy system. In these cases, an epicardial patch-based system becomes necessary. In this study, we investigated a newly developed epicardial carbon electrode as an alternative to a standard epicardial titanium patch. METHODS AND RESULTS: A tubular epicardial braided carbon electrode of 7F diameter and 14-cm length applied in a U-shape to the epicardium was compared with a standard left ventricular epicardial 15-cm2 titanium mesh patch (CPI Inc). As cathode, a CPI endocardial lead, a Medtronic lead, or a carbon-platinum-iridium prototype electrode was used. Ventricular fibrillation was induced with a 60-Hz generator and allowed to continue for 10 seconds before a shock was given. Two different biphasic shock waveforms (3.2/2- and 6/6-millisecond) were delivered by the six electrode configurations. Eight dogs (weight, 24.5 +/- 1.3 kg) underwent an up-down defibrillation protocol. The order of testing the epicardial electrodes, the endocardial cathodes, and the waveform was randomized. With the epicardial carbon electrode, the mean defibrillation threshold (DFT) energy decreased 39% to 56% and the voltage decreased 24% to 35% compared with the titanium patch: from 8.3 +/- 2.5 to 4.9 +/- 3.6 J with the CPI lead and the 3.2/2-millisecond waveform, from 6.2 +/- 2.5 to 2.9 +/- 2.1 J with the carbon-platinum-iridium prototype, and from 6.4 +/- 3.4 J to 3.5 +/- 2.6 J with the Medtronic lead (P < or = .05). The DFT determinations with the 6/6-millisecond biphasic waveform showed a similar trend with slightly higher values. CONCLUSIONS: Compared with a titanium patch, the new braided epicardial electrode significantly decreases the defibrillation energy requirements. This effect can be maximized by using an endocardial carbon-platinum-iridium prototype as cathode and a short duration biphasic waveform.
Alt et al. (Sun,) conducted a rct in Ventricular fibrillation (n=8). Epicardial carbon electrode vs. Standard epicardial titanium patch was evaluated on Mean defibrillation threshold (DFT) energy (39% to 56% decrease, p=<=0.05). A new braided epicardial carbon electrode significantly decreased mean defibrillation threshold energy by 39% to 56% compared with a standard titanium patch (P<=0.05).