The Effect Of Pulse Duration On Efficacy Of Ventricular Defibrillation

Objective: The aim of this study was to evaluate the effect of different pulse duration on efficacy of ventricular defibrillation using automated external defibrillator (AED). At the precondition of guaranteed defibrillation achievement ratio,to search the pathway of low energy defibrillation.Methods: To insert right ventricular lead by venepuncture of femoral vein in order to induce VT/VF by alternating current stimulus. Then after ten seconds of VF, the pigs randomly received defibrillation with biphasic waveforms which pulse duration was from 0.3ms+1ms+0.3ms to 5ms+1ms+5ms.Recording the defibrillation of voltage,energy and defibrillation achievement to appraise its defibrillation efficiency.Results: All pigs underwent 411 defibrillations, successful defibrillations 110. The total defibrillation threshold of energy is (14.40±8.57)J, the total defibrillation threshold of electric quantity is(0.02±0 .01)C and the total defibrillation threshold of voltage is(768.16±321.21)V. The total defibrillation success rate is 26.8% ,The minimum defibrillation threshold of energy is(9.07±3.82)J in 1ms+1ms +1ms group,The defibrillation success rate of 2ms+1ms+2ms group is super to other group(54.9%,P=0.06).The different group has significant difference on defibrillation threshold of voltage ,energy , defibrillation achievement ratio ,and electric quantity from 5ms+1ms +5ms group to 0.3ms+1ms+0.3ms group(P<0.05)Conclusion: The pulse duration is an important influence factor for defibrillation efficacy and through the study we found to shorten the pulse duration may decrease defibrillation threshold and improve the efficacy of defibrillation.