Pyruvate improves cardiac electromechanical and metabolic recovery from cardiopulmonary arrest and resuscitation.
Severe depletion of myocardial energy and antioxidant resources during cardiac arrest culminates in electromechanical dysfunction following recovery of spontaneous circulation (ROSC). A metabolic fuel and natural antioxidant, pyruvate augments myocardial energy and antioxidant redox states in parallel with its enhancement of contractile performance of stunned and oxidant-challenged hearts. This study tested whether pyruvate improves post-arrest cardiac function and metabolism. Beagles were subjected to 5 min cardiac arrest and 5 min open-chest cardiac compression (OCCC: 80 compressions min(-1); aortic pressure 60-70 mmHg), then epicardial dc countershocks (5-10 J) were applied to restore sinus rhythm. Pyruvate was infused i.v. throughout OCCC and the first 25 min ROSC to a steady-state arterial concentration of 3.6+/-0.2 mM. Control experiments received NaCl infusions. Phosphocreatine phosphorylation potential (approximately PCr) and glutathione/glutathione disulfide ratio (GSH/GSSG), measured in snap-frozen left ventricle, indexed energy and antioxidant redox states, respectively. In control experiments, left ventricular pressure development, dP/dt and carotid flow initially recovered upon defibrillation, but then fell 40-50% by 3 h ROSC. ST segment displacement in lead II ECG persisted throughout ROSC. Approximately PCr collapsed and GSH/GSSG fell 61% during arrest. Both variables recovered partially during OCCC and completely during ROSC. Pyruvate temporarily increased approximately PCr and GSH/GSSG during OCCC and the first 25 min ROSC and enhanced pressure development, dP/dt and carotid flow at 15-25 min ROSC. Contractile function stabilized and ECG normalized at 2-3 h ROSC, despite post-infusion pyruvate clearance and waning of its metabolic benefits. In conclusion, intravenous pyruvate therapy increases energy reserves and antioxidant defenses of resuscitated myocardium. These temporary metabolic improvements support post-arrest recovery of cardiac electromechanical performance.
Sharma
Arti B
AB
Department of Integrative Physiology, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX 76107-2699, USA.
Knott
E Marty
EM
Bi
Jian
J
Martinez
Rodolfo R
RR
Sun
Jie
J
Mallet
Robert T
RT
D000704:Analysis of Variance; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D016887:Cardiopulmonary Resuscitation; D004285:Dogs; D004734:Energy Metabolism; D006323:Heart Arrest / Q000628:therapy*; D006439:Hemodynamics / Q000187:drug effects*; D009200:Myocardial Contraction / Q000187:drug effects; D009206:Myocardium / Q000378:metabolism*; D019289:Pyruvic Acid / Q000494:pharmacology*; D016896:Treatment Outcome
D000975:Antioxidants; D019289:Pyruvic Acid