Museedi Abdulrahman S., Mohan Jay
University of Texas HSC
Michigan State University
Percutaneous mechanical support devices have been used widely in clinical practice. The first use of mechanical support was in the 1960s with the intra-aortic balloon pump. This device had seen wide use as it was relatively small and easy to place; however, it offered limited support, augmenting cardiac output by only 0.5 L/min. Until recently, percutaneous options for mechanical support have been limited until the advent of the percutaneously inserted axial flow pump ventricular assist device. The percutaneously inserted ventricular assist device (LVD) is a nonpulsatile axial flow pump that crosses the aortic valve and pumps blood from the left ventricle (LV) to the aorta. The FDA has approved percutaneously inserted LVD for partial circulatory support since 2008. There are multiple different types of percutaneously inserted LVD that provide different levels of support. A percutaneously inserted LVD that provides a maximum flow rate of 2.5 L/min was the first device approved. Another percutaneously inserted LVD has a maximum rate of 5 L/min for full circulatory support; however, it requires surgical cut down for implantation. Finally, an intermediate level device was developed to offer an intermediate level of support of 3.0 to 4.0 L/min and can be placed percutaneously. The percutaneously inserted LVD has impactful effects on the hemodynamic by decreasing the load on the left ventricle and myocardial oxygen consumption, subsequently improving cardiac output and reducing left ventricular end-diastolic pressure, leading to improvement in the coronary perfusion and systemic mean arterial pressure. Additionally, by improving forward output, percutaneously inserted LVD reduces left atrial pressures leading to right ventricle afterload reduction. Other variations of the percutaneously implanted assist devices have since undergone development to aid in providing mechanical circulatory support. The percutaneously inserted right ventricle assist device (RVD) was designed to be used in right ventricular (RV) failure and is a 22 French nonpulsatile axial flow pump mounted on an 11 Fr catheter and positioned via femoral venous access. The inflow of percutaneously inserted right ventricle assist device (RVD) is placed in the inferior vena cava and the outflow in the pulmonary artery. It can provide up to 4 L/min flow to help support a failing RV.
经皮机械支持装置已在临床实践中广泛应用。机械支持的首次应用是在20世纪60年代，使用的是主动脉内球囊泵。该装置因其相对较小且易于放置而得到广泛应用；然而，它提供的支持有限，仅能使心输出量增加0.5升/分钟。直到最近，在经皮插入式轴流泵心室辅助装置出现之前，经皮机械支持的选择一直有限。经皮插入式心室辅助装置（LVD）是一种非搏动性轴流泵，穿过主动脉瓣，将血液从左心室（LV）泵入主动脉。自2008年以来，美国食品药品监督管理局（FDA）已批准经皮插入式LVD用于部分循环支持。有多种不同类型的经皮插入式LVD，可提供不同程度的支持。第一种获得批准的装置是最大流速为2.5升/分钟的经皮插入式LVD。另一种经皮插入式LVD最大流速为5升/分钟，用于全循环支持；然而，它需要通过手术切开进行植入。最后，开发了一种中级装置，可提供3.0至4.0升/分钟的中级支持，且可经皮放置。经皮插入式LVD通过降低左心室负荷和心肌氧消耗，对血流动力学产生显著影响，随后改善心输出量并降低左心室舒张末期压力，从而改善冠状动脉灌注和全身平均动脉压。此外，通过提高前向输出量，经皮插入式LVD降低左心房压力，从而降低右心室后负荷。此后，经皮植入辅助装置的其他变体也在不断发展，以帮助提供机械循环支持。经皮插入式右心室辅助装置（RVD）设计用于右心室（RV）衰竭，是一个安装在11F导管上的22F非搏动性轴流泵，通过股静脉通路定位。经皮插入式右心室辅助装置（RVD）的流入端置于下腔静脉，流出端置于肺动脉。它可提供高达4升/分钟的流量，以帮助支持衰竭的右心室。
