Sarver Heart Center, University of Arizona College of Medicine, Tucson, 85724-5037, USA.
Circ Arrhythm Electrophysiol. 2011 Jun;4(3):337-43. doi: 10.1161/CIRCEP.110.960419. Epub 2011 Apr 14.
In cardiac arrest, the ventricular fibrillation (VF) waveform, particularly amplitude spectral area (AMSA) and slope, predicts the return of spontaneous circulation (ROSC), but it is unknown whether the predictive utility differs in an acute myocardial infarction (MI), prior MI, or normal myocardium and if the waveform can distinguish the underlying myocardial state. We hypothesized that in a swine model of VF cardiac arrest, AMSA and slope predict ROSC after a shock independent of substrate and distinguish an acute from nonacute MI state.
MI was induced by occlusion of the left anterior descending artery. Post MI swine recovered for a 2-week period before induction of VF. VF was untreated for 8 minutes in 10 acute MI, 10 post MI, and 10 control swine. AMSA and slope predicted ROSC after a shock independent of myocardial state. For AMSA >31 mV-Hz, the odds ratio was 62 (P≤0.001) compared with AMSA <19 mV-Hz. For slope >3.1 mV/s, odds ratio was 52 (P≤0.001) compared with slope <1.8 mV/s. With chest compressions, AMSA and slope were significantly lower for acute MI swine compared with control swine, whereas in post MI swine the waveform characteristics were similar to control swine. In particular, for an AMSA >33.5 mV-Hz, the sensitivity to identify an acute from nonacute (control or post MI) state was 83%.
In a swine model of VF cardiac arrest, AMSA and slope predict ROSC independent of myocardial substrate. Furthermore, with chest compressions, the VF waveform evolves differently and may offer a means to distinguish an acute MI.
在心脏骤停中，心室颤动（VF）波形，尤其是幅度谱面积（AMSA）和斜率，可预测自主循环恢复（ROSC），但尚不清楚其在急性心肌梗死（MI）、陈旧性 MI 或正常心肌中的预测效用是否不同，以及该波形是否可以区分潜在的心肌状态。我们假设，在 VF 心脏骤停的猪模型中，AMSA 和斜率可预测电击后的 ROSC，而与底物无关，并可区分急性和非急性 MI 状态。
通过阻塞左前降支诱导 MI。MI 后猪在诱导 VF 前恢复了 2 周。10 只急性 MI 、10 只陈旧性 MI 和 10 只对照猪的 VF 未经治疗 8 分钟。AMSA 和斜率可预测电击后的 ROSC，而与心肌状态无关。对于 AMSA>31 mV-Hz，优势比为 62（P≤0.001），而 AMSA<19 mV-Hz。对于斜率>3.1 mV/s，优势比为 52（P≤0.001），而斜率<1.8 mV/s。进行胸外按压时，急性 MI 猪的 AMSA 和斜率明显低于对照猪，而陈旧性 MI 猪的波形特征与对照猪相似。特别是，对于 AMSA>33.5 mV-Hz，识别急性与非急性（对照或陈旧性 MI）状态的敏感性为 83%。
在 VF 心脏骤停的猪模型中，AMSA 和斜率可预测 ROSC，而与心肌底物无关。此外，进行胸外按压时，VF 波形会发生不同的演变，并且可能提供一种区分急性 MI 的方法。
