Pathophysiology, diagnosis and management of right ventricular failure: A state of the art review of mechanical support devices

Abstract

The function of the right ventricle (RV) is to drive the forward flow of blood to the pulmonary system for oxygenation before returning to the left ventricle. Due to the thin myocardium of the RV, its function is easily affected by decreased preload, contractile motion abnormalities, or increased afterload. While various etiologies can lead to changes in RV structure and function, sudden changes in RV afterload can cause acute RV failure which is associated with high mortality. Early detection and diagnosis of RV failure is imperative for guiding initial medical management. Echocardiographic findings of reduced tricuspid annular plane systolic excursion (<1.7) and RV wall motion (RV S' <10 cm/s) are quantitatively supportive of RV systolic dysfunction. Medical management commonly involves utilizing diuretics or fluids to optimize RV preload, while correcting the underlying insult to RV function. When medical management alone is insufficient, mechanical circulatory support (MCS) may be necessary. However, the utility of MCS for isolated RV failure remains poorly understood. This review outlines the differences in flow rates, effects on hemodynamics, and advantages/disadvantages of MCS devices such as intra-aortic balloon pump, Impella, centrifugal-flow right ventricular assist devices, extracorporeal membrane oxygenation, and includes a detailed review of the latest clinical trials and studies analyzing the effects of MCS devices in acute RV failure.

Keywords: Extracorporeal membrane oxygenation; Hemodynamics; Impella; Intra-aortic balloon pump; Mechanical circulatory support devices; Right ventricle; Right ventricular assist device.