Defibrillation by strong electric shock remains the only clinically proven method to terminate ventricular fibrillation (VF) and to prevent sudden cardiac death. The defibrillation of atrial fibrillation (AF) on the other hand is hindered by the possibility of inducing a rapid heartbeat, called ventricular tachycardias (VTs). The use of shocks to treat malignant cardiac arrhythmias is associated with a host of adverse effects that include cellular injury from electroporation, cardiac conduction disturbances, mechanical dysfunction, increased mortality, and pain and psychological trauma. Hence, reducing the shock strength required to defibrillate would improve the physiological and psychological health of people requiring defibrillation. Integration into new defibrillators would have the following advantages:
Technical Details:
Johns Hopkins researchers have developed a method to reduce the energy requirements and trauma during a defibrillation by timing electrical stimulation with the beating of the heart. It achieves low-voltage and low-energy defibrillation by converting fibrillation into tachycardia using feedback from the heart to time the defibrillation stimuli. Tachycardia can then be terminated by novel or established tachycardia-termination protocols. Determining the appropriate timing of the shock can be done by implanting sensing electrodes in the heart and then processing their signals, or by correlating electrocardiography (ECG) recordings with the amount of activated tissue. Although sensing or approximating the amount of excitable tissue is necessary for the proposed method to work most effectively, a device could also simply "estimate" the best timing of the stimuli.
Looking for Partners:
develop and commercialize the technology as a method for low-energy defibrillation.
