Three-Dimensional Echocardiographic Measurements of Distance Between Papillary Muscles and Mitral Annulus: Assessment With Three-Dimensional Quantification Software System

Abstract

Preservation of continuity between the mitral annulus and papillary muscles has a beneficial effect on postoperative left ventricular function in patients with mitral valve surgery [1][2][3][4][5]. Even in patients who require total excision of the mitral apparatus, the continuity can be restored with expanded polytetrafluoroethylene (ePTFE) sutures or mitral allograft [6][7][8].Although it is important to determine the proper length of the ePTFE sutures or allograft chordae for the resuspension, measurement of the distances between mitral annulus and papillary muscles has been difficult in clinical setting.Recently, we demonstrated three-dimensional (3D) visualization and quantitation of mitral leaflets and annulus geometry using software system, REAL VIEW ® (Y.D., Ltd, Osaka, Japan), with real-time 3D echocardiographic images [9][10][11][12][13]. Furthermore, the newest version of this software allows us 3D visualization and quantitative assessment of location of papillary muscles [14]. In the present study, we sought to quantify the distance between the mitral annulus and papil- AbstractObjective. Although preservation of mitral annulus and papillary muscle alignment is important in mitral valve surgery, it has been difficult to measure the precise distance between mitral annulus and papillary muscles in clinical setting.We sought to quantify the distances between mitral annulus and papillary muscles by using the 3D quantitation software system, REAL VIEW ® . Methods.We examined 10 patients with functional mitral regurgitation due to dilated cardiomyopathy and 10 normal controls by real-time 3D echocardiography. Using REAL VIEW ® , the 3D images of mitral annulus and the tips of papillary muscles were reconstructed in end-systole. Mitral annular area and circumference, mitral leaflet tenting length and volume, and the 6 distances between the tips of papillary muscles and corresponding points of the mitral annulus were measured three-dimensionally.Results. Patients with functional mitral regurgitation due to dilated cardiomyopathy had larger annular size, apparent leaflet tenting and longer papillary muscle to mitral annular distances compared with the controls.Conclusions. We demonstrated 3D echocardiographic measurements of papillary muscle to mitral annular distances with REAL VIEW ® , in clinical setting. This technique should be applicable to understandable demonstration and quantitative evaluation of subvalvular geometry in various mitral valve diseases. (J Echocardiogr 2008; 3: 67-73)

Geometric description for the anatomy of the mitral valve: A review

“…TA B L E 1 Geometric variables of the MV and healthy and diseased (significant regurgitation) literature ranges (Ranganathan et al, 1970;Kunzelman et al, 1994;Yamaura et al, 2008;Delgado et al, 2009;Sonne et al, 2009;Suri et al, 2009;Lee et al, 2013;Mihaila et al, 2013;Topilsky et al, 2013;Dudzinski and Hung, 2014;Jassar et al, 2014;Jiang et al, 2014;Kim et al, 2014;Pouch et al, 2014;Calleja et al, 2015;Machino-Ohtsuka et al, 2016;Obase et al, 2016;Owais et al, 2016;Deorsola and Bellone, 2018)…”

“…One of the most commonly used classifications of MV disease was designed by Carpentier (1983), sometimes referred to as the F I G U R E 1 0 Distances between PM tips and o'clock points of mitral annulus, in axial (left) and isometric (right) views (adapted from Sakai et al, 1999;Yamaura et al, 2008) Khalighi et al (2017), illustrating the connectivity between branches. Green, blue and orange vertices correspond to chordal origin (at the PM level), bifurcation points and insertion points into the leaflets, respectively 'pathophysiologic triad' (Carpentier et al, 1980).…”

“…The PMs spatial position in humans has been mathematically defined, especially taking into account measurements such as their distance to the mitral annulus or to mitral coaptation (Sakai et al , 1999; Yamaura et al , 2008). Other measures of interest, such as the distance between PM or the inter‐PM angle, have also been employed to describe PM morphology (Figure 9).…”

“…Other measures of interest, such as the distance between PM or the inter‐PM angle, have also been employed to describe PM morphology (Figure 9). Some studies have provided measurements of the PM to five key annular sites named o’clock points (Figure 10) (Sakai et al , 1999; Yamaura et al , 2008). Here, each PM is associated with three distances to the annulus, allowing the description of the 3D spatial position of their tips if assumed to be a unique 3D point.…”

“…Distances between PM tips and o’clock points of mitral annulus, in axial (left) and isometric (right) views (adapted from Sakai et al , 1999; Yamaura et al , 2008). ALPM, anterolateral PM; PMPM, posteromedial PM; 0 o’clock, midpoint of the anterior annular circumference; 2 o’clock, right trigone; 10 o’clock, left trigone; 4 o’clock, separation of posterior and middle scallops of posterior leaflet; 8 o’clock, separation of anterior and middle scallops of posterior leaflet…”