Evaluation of the energy efficiency of the first DC defibrillators

This article addresses the characteristics of the first mass-produced DC defibrillators: the ID-1-VEI (USSR), Prema (Czechoslovak Socialist Republic), and the Cardioverter (USA). Data obtained by simulation cardiomyocyte reactions in the state of simulated fibrillation to the depolarizing pulses delivered by these defibrillators at load impedance values of 25, 50, and 100 Omega were plotted to identify relationships between the fraction of the fibrillation cycle at which the defibrillation pulse causes a long-term extension of the refractory period of the cardiomyocyte (the defibrillation completeness index) and the relative energy of the defibrillation pulse. Results obtained from simulation defibrillator pulses at a load impedance of 25 Omega demonstrated greater energy efficiency for pulses from the Prema defibrillator, presumably associated with the large amplitude of the multiple pulse phases.