AUTHOR=Muraru Denisa , Gavazzoni Mara , Heilbron Francesca , Mihalcea Diana J. , Guta Andrada C. , Radu Noela , Muscogiuri Giuseppe , Tomaselli Michele , Sironi Sandro , Parati Gianfranco , Badano Luigi P. 

TITLE=Reference ranges of tricuspid annulus geometry in healthy adults using a dedicated three-dimensional echocardiography software package

JOURNAL=Frontiers in Cardiovascular Medicine

VOLUME=9

YEAR=2022

URL=https://www.frontiersin.org/journals/cardiovascular-medicine/articles/10.3389/fcvm.2022.1011931

DOI=10.3389/fcvm.2022.1011931

ISSN=2297-055X

ABSTRACT=<sec><title>Background</title><p>Tricuspid annulus (TA) sizing is essential for planning percutaneous or surgical tricuspid procedures. According to current guidelines, TA linear dimension should be assessed using two-dimensional echocardiography (2DE). However, TA is a complex three-dimensional (3D) structure.</p></sec><sec><title>Aim</title><p>Identify the reference values for TA geometry and dynamics and its physiological determinants using a commercially available three-dimensional echocardiography (3DE) software package dedicated to the tricuspid valve (4D AutoTVQ, GE).</p></sec><sec><title>Methods</title><p>A total of 254 healthy volunteers (113 men, 47 ± 11 years) were evaluated using 2DE and 3DE. TA 3D area, perimeter, diameters, and sphericity index were assessed at mid-systole, early- and end-diastole. Right atrial (RA) and ventricular (RV) end-diastolic and end-systolic volumes were also measured by 3DE.</p></sec><sec><title>Results</title><p>The feasibility of the 3DE analysis of TA was 90%. TA 3D area, perimeter, and diameters were largest at end-diastole and smallest at mid-systole. Reference values of TA at end-diastole were 9.6 ± 2.1 cm<sup>2</sup> for the area, 11.2 ± 1.2 cm for perimeter, and 38 ± 4 mm, 31 ± 4 mm, 33 ± 4 mm, and 34 ± 5 mm for major, minor, 4-chamber and 2-chamber diameters, respectively. TA end-diastolic sphericity index was 81 ± 11%. All TA parameters were correlated with body surface area (BSA) (<italic>r</italic> from 0.42 to 0.58, <italic>p</italic> &lt; 0.001). TA 3D area and 4-chamber diameter were significantly larger in men than in women, independent of BSA (<italic>p</italic> &lt; 0.0001). There was no significant relationship between TA metrics with age, except for the TA minor diameter (<italic>r</italic> = −0.17, <italic>p</italic> &lt; 0.05). When measured by 2DE in 4-chamber (29 ± 5 mm) and RV-focused (30 ± 5 mm) views, both TA diameters resulted significantly smaller than the 4-chamber (33 ± 4 mm; <italic>p</italic> &lt; 0.0001), and the major TA diameters (38 ± 4 mm; <italic>p</italic> &lt; 0.0001) measured by 3DE. At multivariable linear regression analysis, RA maximal volume was independently associated with both TA 3D area at mid-systole (<italic>R</italic><sup>2</sup> = 0.511, <italic>p</italic> &lt; 0.0001) and end-diastole (<italic>R</italic><sup>2</sup> = 0.506, <italic>p</italic> &lt; 0.0001), whereas BSA (<italic>R</italic><sup>2</sup> = 0.526, <italic>p</italic> &lt; 0.0001) was associated only to mid-systolic TA 3D area.</p></sec><sec><title>Conclusions</title><p>Reference values for TA metrics should be sex-specific and indexed to BSA. 2DE underestimates actual 3DE TA dimensions. RA maximum volume was the only independent echocardiographic parameter associated with TA 3D area in healthy subjects.</p></sec>