Comparative Study of Continuous and Pulsatile Left Ventricular Assist Devices on Hemodynamics of a Pediatric End-to-Side Anastomotic Graft.
Comparative Study of Continuous and Pulsatile Left Ventricular Assist Devices on Hemodynamics of a Pediatric End-to-Side Anastomotic Graft.
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DOI：
10.1007/s13239-010-0006-6
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发表时间：
2010-03
影响因子：
1.8
通讯作者：
Manning, Keefe B
中科院分区：
文献类型：
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作者：
Yang, Ning;Deutsch, Steven;Paterson, Eric G;Manning, Keefe B
尽管有许多研究关注于了解与心室辅助装置（VAD）相关的泵送模式（连续与脉动）对儿科血管脉动性的影响，但对局部血流动力学的影响在很大程度上被忽略了。因此，我们比较不仅指示脉动的血流动力学参数，但也在主动脉和大血管起源于主动脉弓的局部流场。一个生理移植物吻合模型是建立在儿科，患者特定的，主动脉与附在升主动脉上的移植物。使用先前验证的二阶精确的Navier-Stokes流求解器基于有限体积法来模拟流动。主要研究结果如下：（1）与连续支持相比，脉动支持提供了更大程度的血管脉动性，然而，其仍然比健康主动脉中的脉动性小20%;（2）脉动支持增加了大血管中的流量，而连续支持减少了大血管中的流量;（3）完全VAD支持导致主动脉中的湍流，脉动支持和连续支持的最大主雷诺应力分别为7081和249 dyn/cm 2;（4）完全脉动支持导致主动脉中预期溶血显著增加;（5）脉动支持比连续支持在主动脉中引起更高的时间平均壁剪切应力（WSS）和振荡剪切指数（OSI）。这些发现将有助于确定搏动性和连续性VAD儿科患者的移植物失效风险。
Although there are many studies that focus on understanding the consequence of pumping mode (continuous vs. pulsatile) associated with ventricular assist devices (VADs) on pediatric vascular pulsatility, the impact on local hemodynamics has been largely ignored. Hence, we compare not only the hemodynamic parameters indicative of pulsatility but also the local flow fields in the aorta and the great vessels originating from the aortic arch. A physiologic graft anastomotic model is constructed based on a pediatric, patient specific, aorta with a graft attached on the ascending aorta. The flow is simulated using a previously validated second-order accurate Navier–Stokes flow solver based upon a finite volume approach. The major findings are: (1) pulsatile support provides a greater degree of vascular pulsatility when compared to continuous support, which, however, is still 20% less than pulsatility in the healthy aorta; (2) pulsatile support increases the flow in the great vessels, while continuous support decreases it; (3) complete VAD support results in turbulence in the aorta, with maximum principal Reynolds stresses for pulsatile support and continuous support of 7081 and 249 dyn/cm2, respectively; (4) complete pulsatile support results in a significant increase in predicted hemolysis in the aorta; and (5) pulsatile support causes both higher time-averaged wall shear stresses (WSS) and oscillatory shear indices (OSI) in the aorta than does continuous support. These findings will help to identify the risk of graft failure for pediatric patients with pulsatile and continuous VADs.