| Sumario: | The right atrium (RA) plays a vital role in the electromechanical regulation of the
heart. Various invasive and non-invasive techniques have been used to elucidate right
atrial structure and function. One such novel technique is speckle-tracking
echocardiography (STE). Speckle tracking-derived deformation is a relatively new
parameter, which is less dependent on loading conditions. STE tracks acoustic scatters
(speckles) of myocardium, frame by frame, to calculate the strain or deformation
indices of the myocardium. The right atrium is a relatively neglected chamber as it is
mostly studied for assessment of atrial mass lesions, congenital and acquired valve
lesions and for electro physiological studies. However, its role in the systolic and
diastolic function of the right ventricle of the heart has been less explored. I have
adapted the STE technique, designed for left ventricular analysis, for use in the right
atrial analysis. I undertook a reproducibility study for right atrial deformation
parameters and defined normal reference ranges for longitudinal deformation
parameters. I have found the analysis approach used generates similar values to those
reported in the limited number of previous studies on right atrial STE. I then compared
STE derived strain with cardiovascular magnetic resonance feature tracking derived
measures of right atrial strain and found moderate agreement between the two
techniques. Finally, I investigated whether there are differences in right atrial
longitudinal deformation parameters in different patient disease groups. I studied those
with Heart Failure with Normal Ejection Fraction (HFNEF) and found a decrease in
right atrial function. Whereas, in another cohort of patients with Rheumatoid Arthritis
(RhA) there was no statistical difference compared to healthy controls. This thesis
therefore demonstrates the feasibility of using STE to measure right atrial strain and
provides evidence that right atrial strain does vary in certain disease conditions.
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