The Journal of Thoracic and Cardiovascular Surgery, Vol 69, 729-735, Copyright © 1975 by The American Association for Thoracic Surgery and The Western Thoracic Surgical Association
Restoration of myocardial bioenergetic metabolism in swine after periods of ischemic ventricular fibrillation
FP Skinner, MG Levitzky, RF Scott and J Fricks
Myocardial mitochondrial function and high energy phosphate levels were
measured in normal swine, in swine after either 5 or 10 minutes of ischemic
ventricular fibrillation (IVF) while on cardiopulmonary bypass, and in
swine defibrillated after either 5 or 10 minutes of IVE. The damage to
myocardial mitochondria induced by IVF, such as partial uncoupling,
decreased oxygen uptake, and loss of cytochrome oxidase activity, was
completely reversed almost instantly by coronary artery perfusion and the
restoration of sinus rhythm. After either 5 or 10 minutes of IVF followed
by coronary artery reperfusion and defibrillation, myocardial creatine
phosphate (CP), adenosine monophosphate (AMP) and adenosine diphosphate
(ADP) return to normal levels very rapidly. However, adenosine triphosphate
(ATP) levels remain significantly lower than control levels. If the
bioenergetic mechanisms of swine and human myocardium are similar, it
appears that IVF at least for a 10 minute period produces no damage to
myocardial mitochondria that is not corrected by perfusion of the coronary
arteries and re-establishment of sinus rhythm. Furthermore, sinus rhythm
can be re-established and maintained despite signficantly lower levels of
myocardial ATP.