Validation of a Holographic Display for Quantification of Mitral Annular Dynamics by Three-Dimensional Echocardiography

• Published in: Journal of the American Society of Echocardiography Vol. 32; no. 2; pp. 303 - 316.e4
• Main Authors: Dumont, Karl-Andreas, Kvitting, John-Peder Escobar, Karlsen, Jørn S., Remme, Espen W., Hausken, John, Lundblad, Runar, Fiane, Arnt E., Urheim, Stig
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.02.2019
• Subjects: 3D echocardiography; Mitral valve; Mitral valve annulus; Sonomicrometry; Mitral valve; AHCWR; VSAS; LV; MPR; Mitral valve annulus; 3D; 2D; CW; IVC; SL; 3D echocardiography; Sonomicrometry; NPA
• ISSN: 0894-7317; 1097-6795
• DOI: 10.1016/j.echo.2018.08.010

Three-dimensional (3D) echocardiography with multiplanar reconstruction (MPR) is used clinically to quantify the mitral annulus. MPR images are, however, presented on a two-dimensional screen, calling into question their accuracy. An alternative to MPR is an autostereoscopic holographic display that enables in-depth visualization of 3D echocardiographic data without the need for special glasses. The aim of this study was to validate an autostereoscopic display using sonomicrometry as a gold standard. In 11 anesthetized open-chest pigs, sonomicrometric crystals were placed along the mitral annulus and near the left ventricular apex. High-fidelity catheters measured left atrial and ventricular pressures. Adjustments of pre- and afterload were done by constriction of the inferior vena cava and the ascending aorta, respectively. Three-dimensional epicardial echocardiography was obtained from an apical view and converted to the autostereoscopic display. A 3D virtual semitransparent annular surface (VSAS) was generated to measure commissure width (CW), septal-lateral length, area of the mitral annular surface, nonplanarity angle, and the annular height–to–commissure width ratio in mid-systole and late diastole. Mitral annular measurements from the 3D VSAS derived from the 3D echocardiographic images and autostereoscopic display correlated well with sonomicrometry over a range of loading conditions: CW length (r = 0.98, P < .00001), septal-lateral length (r = 0.98, P < .00001), annular surface area (r = 0.93, P < .001), nonplanarity angle (r = 0.87, P < .001), and annular height–to–commissure width ratio (r = 0.85, P < .01). The 3D VSAS showed better agreement with the sonomicrometric measurements compared with MPR. Mitral annular measurements using 3D VSAS correlate well with sonomicrometry over a range of loading conditions and may represent a powerful tool for noninvasive quantification of mitral annular dynamics. •Quantification of the 3D mitral annulus is challenging.•Inconsistent data on mitral annulus is questioning how measures are quantified.•The display enables visualization of 3D echocardiographic data without glasses.•Mitral annular measurements from the display correlated well with sonomicrometry.•Better agreement with sonomicrometry was demonstrated with the display than with MPR.