Preexisting severe left ventricular dysfunction in swine undergoing acute coronary occlusion resulted in pulseless electrical activity in 100% of cases within 1.7 minutes.
Does preexisting severe left ventricular dysfunction alter the initial cardiac arrest rhythm during acute coronary occlusion in a swine model?
Acute coronary ischemia in the setting of severe left ventricular dysfunction produces PEA almost immediately due to acute pump failure, suggesting patients with baseline LV dysfunction and PEA should be evaluated for acute coronary occlusion.
Absolute Event Rate: 100% vs 2.9%
Background Pulseless electrical activity (PEA) is a common initial rhythm in cardiac arrest. A substantial number of PEA arrests are caused by coronary ischemia in the setting of acute coronary occlusion, but the underlying mechanism is not well understood. We hypothesized that the initial rhythm in patients with acute coronary occlusion is more likely to be PEA than ventricular fibrillation in those with prearrest severe left ventricular dysfunction. Methods and Results We studied the initial cardiac arrest rhythm induced by acute left anterior descending coronary occlusion in swine without and with preexisting severe left ventricular dysfunction induced by prior infarcts in non-left anterior descending coronary territories. Balloon occlusion resulted in ventricular fibrillation in 18 of 34 naïve animals, occurring 23.5±9.0 minutes following occlusion, and PEA in 1 animal. However, all 18 animals with severe prearrest left ventricular dysfunction (ejection fraction 15±5%) developed PEA 1.7±1.1 minutes after occlusion. Conclusions Acute coronary ischemia in the setting of severe left ventricular dysfunction produces PEA because of acute pump failure, which occurs almost immediately after coronary occlusion. After the onset of coronary ischemia, PEA occurred significantly earlier than ventricular fibrillation (<2 minutes versus 20 minutes). These findings support the notion that patients with baseline left ventricular dysfunction and suspected coronary disease who develop PEA should be evaluated for acute coronary occlusion.
Ambinder et al. (Mon,) conducted a other in Acute coronary occlusion and cardiac arrest (n=52). Preexisting severe left ventricular dysfunction vs. Naïve animals (without preexisting severe left ventricular dysfunction) was evaluated on Initial cardiac arrest rhythm (pulseless electrical activity vs ventricular fibrillation). Preexisting severe left ventricular dysfunction in swine undergoing acute coronary occlusion resulted in pulseless electrical activity in 100% of cases within 1.7 minutes.