Ascending Defibrillation Waveform Significantly Reduces Myocardial Morphological Damage and Injury Current

Academic Article


  • Objectives: This study tested the hypothesis that a biphasic defibrillation waveform with an ascending first phase (ASC) causes less myocardial damage by pathology and injury current than a standard biphasic truncated exponential (BTE) waveform in a swine model. Background: Although lifesaving, defibrillation shocks have significant iatrogenic effects that reduce their benefit for patient survival. Methods: An ASC waveform with an 8-ms linear ramp followed by an additional positive 0.5-ms decaying portion with amplitudes of 20 J (ASC 20J) and 25 J (ASC 25J) was used. The control was a 25-J BTE conventional waveform (BTE 25J) Results: The ASC 20J and ASC 25J shocks were both successful in 6 of 6 pigs, but the BTE 25J was successful in only 6 of 14 pigs (p < 0.05). Post-shock ST-segment elevation (injury current) in the right ventricular electrode was significantly greater with BTE 25J than with ASC 20J and ASC 25J. With a blinded pathology reading, hemorrhage, inflammation, thrombi, and necrosis 24 h post-shock were significantly greater with BTE 25J than with ASC 20J and ASC 25J. Troponin levels were also markedly lower at 3, 4, 5, and 6 h post-shock. Conclusions: Defibrillation shocks cause electrophysiological, histological, and biochemical signs of myocardial damage and necrosis. These signs of damage are markedly less for an ASC waveform than for a conventional BTE waveform.
  • Authors

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    Digital Object Identifier (doi)

    Author List

  • Huang J; Ruse RB; Walcott GP; Litovsky S; Bohanan SJ; Gong DW; Kroll MW
  • Start Page

  • 854
  • End Page

  • 862
  • Volume

  • 5
  • Issue

  • 7