Abstract 15143: Painless Epicardial Implantable Cardioverter Defibrillator Net System With Electric Conductive Fibers

Abstract

Introduction: Current Implantable cardioverter-defibrillator (ICD) needs high CD shock (35J), which is not tolerable under consciousness. Our multi-physics computer-simulation demonstrated extra-low energy defibrillation (0.36J)can be possible if sheet electrodes are arranged upper (base) and lower (apex) side of the heart. Hypothesis: We developed the epicardial ICD net electrodes system (Ep-ICD) made of upper and lower parts with fine conductive fibers. The objective of this study was to test whether Ep-ICD can stop ventricular fibrillation with painless level (<0.7J) in large animal model. Methods: Ep-ICD was constructed by fine tungsten fibers using computer-assisted knitting machine (Shimaseiki Co., Japan). Middle part was knitted by polyester fibers. Upper and lower electrode nets were connected to RV and SVC coils of DF-1 lead (Medtronic), respectively. Five beagle dogs were used for this experiment. The Ep-ICD net was directly attached to the heart, and electrodes were connected to commercially available ICD system. DC discharges were controlled by telemetry controller. Vf was induced by attaching 9V battery onto the heart surface. Ten seconds after Vf induction, DC was delievered from minimal energy 0.4J (Medtronic Viva XT) or 0.1J (Boston Scientific Perciva). DC energy was gradually increased until defibrillation was accomplished. After 3 minutes of recovery, the ventricular fibrillation induction and defibrillation tests were repeated. Defibrillation threshold (DFT) was defined as 75% of success of defibrillation. To compare current ICD system, commercial ICD lead was inserted in one dog through internal juglar vein, and defibrillation test was conducted. Results: Defibrillation was accomplished by 0.1J~1J, All hearts recovered instantaneously to sinus rhythm. DFT were 0.6J for 4 dogs and 0.8J for one dog. Current ICD system needed 30J for defibrillation. Conclusions: Our preliminary results shows that the Ep-ICD accomplished defibrillation with painless level of DC energy (<0.7J). Extra-low energy DC can avoid electroporation which causes conduction abnormality or malignant arrhythmia. Ep-ICD can apply DC shock before losing consciousness, which has a huge merit for QOL.