Percutaneously Inserted Ventricular Assist Device

Excerpt

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.