In-vivo myocardial substrate alteration during perfused ventricular fibrillation.
In-vivo myocardial substrate alteration during perfused ventricular fibrillation.
复制标题
灌注心室颤动期间体内心肌基质的变化。
DOI：
10.1111/j.1553-2712.1999.tb00409.x
复制
发表时间：
1999
期刊：
影响因子：
--
通讯作者：
Robitaille,PM
中科院分区：
文献类型：
--
作者：
Angelos,MG;Torres,CA;Rath,DP;Zhu,H;Beckley,PD;Robitaille,PM
目的：早期的研究表明，活体心脏会改变其底物的利用，作为心脏做功的函数。以前的工作也证明了在室颤(VF)时心脏对氧气的高需求。作者假设，在负荷增加的情况下，VF期间心肌基质的利用与正常跳动的心脏相似。方法：采用~(13)C核磁共振(~(13)C核磁共振)技术，在增加心脏做功(多巴酚丁胺组)和室颤加体外灌流(VF组)条件下，研究活体猪心肌基质的选择。一旦动物准备完成，通过向左冠状动脉前降支(LAD)注入未标记的醋酸盐，达到代谢稳定状态。然后将注入的底物改为[2-13C]乙酸酯，并用13C核磁共振监测谷氨酸池标记。使用配对t检验比较基线和增加工作负荷(多巴酚丁胺组)或灌注室颤组(VF组)干预后的谷氨酸C4共振区。结果：两组间的基础主动脉和心脏大静脉乳酸、血糖水平、血气、血红蛋白水平和体温相似。两组C4谷氨酸峰的标记均较基线显著减少(多巴酚丁胺组：20.2±14.9vs84.7±32.7，p=0.002；VF组：49.8±24.4vs83.9±24.4，p=0.02)，提示对醋酸酯氧化的选择有利于其他内源性底物。结论：在活体心脏中，尽管没有功能性收缩，但在灌流VF期间底物利用的变化与正常跳动心脏中随着工作负荷增加而发生的变化相似。
Objectives: Earlier work suggests the invivo heart alters its substrate utilization as a function of cardiac work. Previous work has also demonstrated the high oxygen requirements of the heart during ventricular fibrillation (VF). The authors hypothesized that myocardial substrate utilization during VF with perfusion is similar to the normal beating heart under conditions of increased workload. Methods: Myocardial substrate selection was studied in the invivo porcine myocardium using13carbon nuclear magnetic resonance (13C NMR) under conditions of increased cardiac work (dobutamine group) and VF with extracorporeal perfusion (VF group). Once the animal preparation was completed, metabolic steady state was achieved with the infusion of unlabeled acetate into the left anterior descending (LAD) coronary artery. The infused substrate was then changed to [2‐13C] acetate and glutamate pool labeling was monitored by13C NMR. The glutamate C4 resonance areas at baseline and after intervention of either increased workload (dobutamine group) or perfused VF (VF group) were compared within groups using paired t‐tests. Results: Baseline aortic and great cardiac vein lactates, glucose levels, blood gases, hemoglobin levels, and temperatures were similar between groups. In both groups, there was a significant decrease from baseline in the labeling of C4 glutamate peaks (dobutamine group: 20.2 ± 14.9 vs 84.7 ± 32.7, p = 0.002; and VF group: 49.8 ± 24.4 vs 83.9 ± 24.4, p = 0.02), indicating selection against acetate oxidation in favor of other endogenous substrates. Conclusions: In the in‐vivo heart, despite the absence of functional contractions, changes in substrate utilization during perfused VF are similar to changes that occur with increased workload in the normal beating heart.