Potential Diagnostic and Prognostic Values of Left Atrial Strain in Valvular Heart Disease

Abstract

There has been increasing evidence supporting the importance of left atrial (LA) functional analysis and measurement in various physiologic and pathologic cardiovascular conditions due to its high diagnostic and prognostic values. Assessment of LA strain (LAS) has emerged as an early marker of subclinical LA dysfunction. Using speckle-tracking echocardiography, LAS can be measured in all phases of LA function (reservoir, conduit, and booster pump). In valvular heart disease (VHD), surgical and nonsurgical interventions should be performed before irreversible left ventricular (LV) and/or LA myocardial dysfunction. The current guidelines recommended using LV strain as a parameter for early detection and timely intervention. Currently, many published data have shown the diagnostic and prognostic values of LAS in VHD, which is encouraging to integrate LAS during echo assessment. In this review, we aim to collect the current data about the clinical utility of LAS changes in risk stratification, predicting outcome, and guiding the time of intervention in VHD. The review summarized these data according to the type of valve pathologies.

Keywords: Left atrial strain; left atrium; speckle-tracking echocardiography; valvular heart disease.

Figure 1

Display of normal left atrial strain (LAS) curve and values in the three phases (LAS-reservoir, LAS-conduit, and LAS-contractile) as obtained from the apical four-chamber view, (a) Using the onset of QRS as starting point (ED), (b) Using the onset of the P-wave as starting point (AC). LAS-r = Left atrial strain reservoir, LAS-cd = Left atrial strain conduit, LAS-ct = Left atrial strain contractile

Figure 2

Example of patient with severe aortic stenosis; (a) Left atrial strain (LAS) curve and values in all phases showed marked reduction of LAS-reservoir and slight reduction of LAS-conduit and LAS-contractile, (b) Parasternal long-axis view showing severely calcific aortic valve (AV), and (c) Continuous wave Doppler measurement of maximum and mean pressure gradient across the AV. LAS-r = Left atrial strain reservoir, LAS-cd = Left atrial strain conduit, LAS-ct = Left atrial strain contractile

Figure 3

Example of patient with severe mitral regurgitation (MR); (a) Left atrial strain (LAS) curve and values in all phases showed marked reduction of LAS-reservoir and LAS-contractile with mild reduction of LAS-conduit, (b) Apical four-chamber view with color Doppler showing jet of severe MR, and (c) Continuous wave Doppler across the mitral valve showing the Doppler density of the severe MR jet. LAS-r = Left atrial strain reservoir, LAS-cd = Left atrial strain conduit, LAS-ct = Left atrial strain contractile, LV = Left ventricular, LA = Left atrial

Figure 4

Example of patient with moderate-to-severe mitral stenosis; (a) Left atrial strain (LAS) curve and values in all phases showed marked reduction of LAS-reservoir, LAS-contractile, and LAS-conduit, (b) Two-dimensional echo showing mitral valve orifice in short-axis view, and (c) Apical four-chamber view showing doming of both mitral valve leaflets with restricted opening. LAS-r = Left atrial strain reservoir, LAS-cd = Left atrial strain conduit, LAS-ct = Left atrial strain contractile

Figure 5

Example of patient with severe tricuspid regurgitation (TR); (a) Left atrial strain (LAS) curve and values in all phases showed marked reduction of LAS-reservoir, LAS-contractile, and LAS-conduit, and (b) Apical four-chamber view with color Doppler showing large jet of severe TR. LAS-r = Left atrial strain reservoir, LAS-cd = Left atrial strain conduit, LAS-ct = Left atrial strain contractile