83 - Low-Flow, Low-Gradient Aortic Stenosis With Preserved Left Ventricular Ejection Fraction

Abstract

Low-flow, low-gradient (LF-LG) aortic stenosis (AS) may occur in the context of either reduced (i.e., “classical” low-flow) or preserved (i.e., “paradoxical” low-flow) left ventricular ejection fraction (LVEF). The purpose of this chapter is to provide an update on the Doppler echocardiographic assessment of paradoxical LF-LG AS. Doppler echocardiography is key to making the differential diagnosis between true paradoxical LF-LG AS and other situations associated with small aortic valve area (AVA) and low gradient (i.e., classical LF-LG and normal flow, low gradient). A particular effort should be made to rule out measurement errors in AS patients with discordant AVA–gradient findings. Symptomatic patients with true paradoxical LF-LG require further investigation, that is, stress echocardiography and/or aortic valve calcium score by multidetector computed tomography to confirm the stenosis severity and the need for aortic valve replacement (AVR). Transcatheter AVR may provide a valuable alternative to surgical AVR in patients with paradoxical LF-LG AS. Optimization of antihypertensive therapy should be considered in these patients regardless of whether they are to be treated conservatively or with surgical or transcatheter valve replacement.