Radio-frequency powered atrial defibrillation with a biphasic rectangular pulse waveform: a safety study at 3 and 5 jouls

A novel device for transvenous atrial defibrillation with a biphasic rectangular pulse waveform, with instant power supplied through a radio-frequency energy-transfer link in a short air gap of up to 18 mm, has been investigated and is briefly described here. Previous waveform assessments, have suggested that a biphasic and asymmetric (second phase at 50% amplitude) pulse waveform of energy discharge is of particular clinical interest. Hence, a safety study upon the haemodynamic effects of such a novel waveform for atrial defibrillation, was carried out on 6 animal models (pigs), at energy levels of 3 J and 5 J. The results demonstrated relatively small and reversible effects on the haemodynamics and the novel waveform was comparable in effect to a conventional, capacitor-based (with RC exponential decay), biphasic waveform. Also, an assessment of the device output performance for various air gap distances is presented.