Valvular Heart Disease in Patients Supported With Left Ventricular Assist Devices
Heart failure (HF) has become increasingly prevalent with the progressive development of HF risk factors in our aging population.1 Although valvular heart disease (VHD) is not similarly considered as a public health concern (overall United States prevalence of 2.5%),2 many patients with advanced systolic HF have concurrent VHD. Because of the limited number of suitable donor organs for cardiac transplantation, advanced HF patients who have refractory or end-stage HF are often treated with left ventricular assist devices (LVADs).3 The impact of concomitant valvular lesions in those undergoing LVAD implantation has not been fully characterized and the management of these lesions is a subject of intense interest, particularly for patients for whom subsequent heart transplantation is not a viable option.
First-generation LVADs exhibited a pulsatile-flow mechanism, using positive displacement to move blood to the periphery.4 These regular intervals help mimic the systole-diastole phases of native cardiac physiology, which differs substantially from the mechanism of newer continuous-flow devices in which a nonpulsatile stream of blood provides systemic circulation. Second- and third-generation continuous-flow LVADs provide smaller size and enhanced durability, allowing for long-term support with improved quality of life.5 However, there are unique implications of contemporary LVAD support on cardiac circulation and valvular mechanics. Chronic unloading of the left ventricle (LV) via continuous, nonpulsatile flow alters blood flow dynamics through the left-sided cardiac chambers, with implications for the aortic valve (AV). Alteration of cardiac mechanics through continuous-flow can also impact the unsupported right ventricle (RV), leading to tricuspid regurgitation (TR). In this review, we aim to provide a background on the most common aortic, tricuspid, and mitral valve pathologies in patients supported with LVADs and highlight the outcomes and management of patients with VHD who undergo LVAD insertion.
AV pathology is uncommon in advanced HF patients before LVAD …