A comparison of electrically induced cardiac arrest with cardiac arrest produced by coronary occlusion.
OBJECTIVE
The present study was undertaken to compare an animal model of electrically induced VF with ischemically induced VF. In a preponderance of models of cardiac arrest and resuscitation in intact animals, ventricular fibrillation (VF) is induced by an alternating current delivered directly to the epicardium or endocardium. Yet, the applicability of such animal models has been challenged for it is not an electrical current alone but rather a current generated in the ischemic myocardium that triggers VF. Accordingly, a potentially more clinically relevant model was investigated in which spontaneous VF followed acute myocardial ischemia.


METHODS
Twenty anesthetized pigs were randomized to either electrical fibrillation or myocardial ischemia following transient occlusion of the left anterior descending (LAD) coronary artery.


RESULTS
VF was untreated for 7 min in both models after which mechanical ventilation and precordial compression were begun. Defibrillation was attempted after 5 min of CPR in both groups. VF appeared within 5.7+/-2.0 min of LAD occlusion.


CONCLUSIONS
A significant increase in the number of post-resuscitation premature ventricular beats and recurrent VF followed ROSC and a significantly greater number of shocks was required for restoration of spontaneous circulation (ROSC) after LAD occlusion. Nevertheless, early post-resuscitation myocardial dysfunction, neurological recovery and 72 h survival were indistinguishable between the two models.
Wang
Jinglan
J
The Weil Institute of Critical Care Medicine, 35100 Bob Hope Drive, Rancho Mirage, CA 92270, United States.
Weil
Max Harry
MH
Tang
Wanchun
W
Chang
Yun-Te
YT
Huang
Lei
L
D000818:Animals; D016887:Cardiopulmonary Resuscitation; D023921:Coronary Stenosis / Q000150:complications*; D004195:Disease Models, Animal; D004554:Electric Countershock / Q000009:adverse effects*; D006323:Heart Arrest / Q000209:etiology* / Q000628:therapy; D008297:Male; D011379:Prognosis; D013552:Swine; D014693:Ventricular Fibrillation / Q000628:therapy*