Weaning of rotary blood pump recipients after myocardial recovery: a computer study of changes in cardiac energetics.
Weaning of rotary blood pump recipients after myocardial recovery: a computer study of changes in cardiac energetics.
复制标题
心肌恢复后旋转血泵接受者的脱机：心脏能量学变化的计算机研究。
DOI：
10.1016/j.jtcvs.2003.09.029
复制
发表时间：
2004
期刊：
影响因子：
--
通讯作者：
E. Wolner
中科院分区：
文献类型：
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作者：
H. Schima;M. Vollkron;H. Boehm;W. Röthy;M. Haisjackl;G. Wieselthaler;E. Wolner
背景心肌恢复后患者脱离机械心脏支持总是涉及多个相互作用的因素，特别是在泵流量减少期间的心肌训练。当支持流量减少甚至接近于零时，旋转泵提供培训优势。我们报告了一个计算机分析，评估部分卸载和移除的旋转pumps.Methods和RTSA计算机模型的辅助循环，以前在MATLAB（MathWorks公司，Natick，马萨诸塞州），心脏所需的工作已经增强了与模型的MicroMed DeBakey心室辅助装置（MicroMed技术公司，休斯顿，德克萨斯州）。计算无辅助和各种持续辅助患者的流量、压力模式和外功（压力-容积面积，计算为心室压力-容积环[外功]的面积加上势能）。在低流量条件下，心脏通过非闭塞性旋转泵施加振荡的前向-反向流动，导致心室做功增加。因此，1至1.5L/min的辅助流量需要与无支撑心脏的功相等的功。在60%收缩力时，非辅助压力-容积面积为1.10 Ws/拍，势能为0.38 Ws/拍。在1 L/min的Qpump下，压力-容积面积为1.21 Ws/拍，势能为0.37 Ws/拍。在3L/min的Qpump下，压力-容积面积为0.93Ws/拍，势能为0.29Ws/拍。这些条件不能实现与脉动systems.CONCLUSIONDuring断奶和再训练，植入的旋转泵可以提供一个工作量的心脏一样，在nonassisted的情况下，从而增加了断奶的可预测性和降低复发性心力衰竭的风险。
BACKGROUNDWeaning of patients from mechanical cardiac support after myocardial recovery has always involved multiple, interacting factors, particularly the training of the myocardium during reduction of pump flow. Rotary pumps offer training advantages when support flow is reduced, even to nearly zero. We report a computer analysis that evaluates the work required of the heart during partial unloading and removal of rotary pumps.METHODS AND RESULTSA computer model of the assisted circulation, previously implemented in MATLAB (The MathWorks Inc, Natick, Mass), has been augmented with a model of the MicroMed DeBakey ventricular assist device (MicroMed Technology, Inc, Houston, Tex). Flow, pressure patterns, and external work (pressure-volume area, calculated as the area of the ventricular pressure-volume loop [external work] plus potential energy) were calculated for nonassisted and various continuously assisted patients. Under low-flow conditions, the heart imposes an oscillating forward–backward flow through the non-occlusive rotary pump, causing an increase in ventricular work. Thus, an assist flow of 1 to 1.5 L/min requires work equivalent to that of the unsupported heart. At 60% contractility, the nonassisted pressure-volume area is 1.10 Ws/beat, and the potential energy is 0.38 Ws/beat. At a Qpump of 1 L/min, the pressure-volume area is 1.21 Ws/beat, and the potential energy is 0.37 Ws/beat. At a Qpump of 3 L/min, the pressure-volume area is 0.93 Ws/beat, and the potential energy is 0.29 Ws/beat. These conditions cannot be achieved with pulsatile systems.CONCLUSIONDuring weaning and retraining, an implanted rotary pump can provide a workload to the heart like that in the nonassisted situation, thus increasing the predictability of weaning and reducing the risk of reiterating heart failure.