Towards impedance optimised transcutaneous atrial defibrillation

Impedance compensated transcutaneous atrial defibrillation may offer more cost effective and less painful treatment for patients with AF by facilitating arrhythmia detection and low-energy synchronized cardioversion in a non-acute care setting. However, the technological barriers to implementation remain significant. In this paper advancements towards the realization of an impedance compensated passive transcutaneous atrial defibrillator architecture are reported: high power transcutaneous inductive link for defibrillation energy transfer, low-power electrocardiogram and impedance sensing for AF detection and optimised cardioversion management via an embedded microcontroller with RF communications link for overall system control. The transcutaneous inductive link has been reliably operated in two distinct modes; `sense mode´ offers a >5W continuous power transfer mode to enable AF-ECG processing and intracardiac impedance measurement prior to cardioversion while `shock mode´ facilitates the transcutaneous coupling of >150W during delivery of an impedance compensated rectilinear defibrillation shock waveform to the heart. Laboratory bench test and experimental results are presented to demonstrate proof of concept.