Narang Nikhil, Raikhelkar Jayant, Sayer Gabriel, Uriel Nir
Section of Cardiology, Department of Medicine, University of Chicago, 5841 South Maryland Avenue, Chicago, IL 60637, USA.
Section of Cardiology, Department of Medicine, University of Chicago, 5841 South Maryland Avenue, Chicago, IL 60637, USA.
Cardiol Clin. 2018 Nov;36(4):561-569. doi: 10.1016/j.ccl.2018.06.013.
Left ventricular assist devices (LVAD) provide a durable option for patients with advanced hear failure. Axial and centrifugal pump physiology differs with regard to the relationship between pump inflow-outflow cannula pressure differential and flow, which results in device behavior that can vary drastically under different loading conditions. Ramp studies can aid the clinician in choosing the optimal speed to adequately unload the left ventricle. Advances in 3-dimensional echocardiography enhance the understanding of chamber geometry for both types of LVADs. Novel outflow graft imaging techniques have been developed to better characterize aortic insufficiency, which may be underestimated with current standard methods.
左心室辅助装置(LVAD)为晚期心力衰竭患者提供了一种持久的治疗选择。轴流泵和离心泵的生理学在泵入流-出流插管压差与流量之间的关系方面存在差异,这导致装置在不同负荷条件下的行为可能有很大变化。斜坡研究有助于临床医生选择最佳速度,以充分减轻左心室的负荷。三维超声心动图技术的进步加深了对两种类型LVAD心室几何结构的理解。已开发出新型流出道移植物成像技术,以更好地描述主动脉瓣关闭不全的情况,目前的标准方法可能会低估这种情况。