Echocardiographic quantification of mitral apparatus morphology and dynamics in patients with dilated cardiomyopathy

Abstract

Mitral regurgitation is among the most common valvular heart diseases. Mitral regurgitation in patients with dilated cardiomyopathy is a complex pathology involving annular dilatation, papillary muscle displacement, systolic leaflet tethering, and left ventricular remodeling. Quantification of mitral apparatus damage in these patients is essential for successful interventional and surgical therapy. Mitral regurgitation in the presence of dilated cardiomyopathy is classified as Carpentier type IIIB, with restricted leaflet mobility as a standard feature. Echocardiography allows accurate evaluation of the complex anatomy and function of the mitral apparatus. Updated guidelines recommend two-dimensional followed by systematic three-dimensional echocardiographic evaluation in patients with mitral regurgitation. New three-dimensional echocardiographic software packages provide many parameters that help identify the precise morphology and function of the various components of the mitral apparatus, helping to determine the etiology of mitral regurgitation and evaluate disease severity. This review provides the first point-by-point approach to the assessment of all old and new echocardiographic methods, from the simplest to the most complex, used to examine the components of the mitral valve apparatus in patients with dilated cardiomyopathy. Although these parameters are still under research, this information will be helpful for establishing therapeutic procedures in a disease with a poor prognosis.

Keywords: Functional mitral regurgitation; dilated cardiomyopathy; echocardiography; mitral valve apparatus component; narrative review; valvular heart disease.

Figure 1.

Graphic representation of the mitral valve apparatus. A1, A2, A3: segments of the anterior mitral valve. P1, P2, P3: segments of the posterior mitral valve.

Figure 2.

Papillary muscles and chordae tendinae. (a) Papillary muscles visualized from the two-dimensional short-axis papillary muscle view. A-L PM: anterolateral papillary muscle, P-M PM: posteromedial papillary muscle and (b) Chordae tendinae visualized from the parasternal long-axis view.

Figure 3.

Mitral regurgitation features in patients with dilated cardiomyopathy. (a) Central color mitral regurgitation jet visualized from parasternal long-axis view. (b) Central color mitral regurgitation jet visualized from apical four-chamber view. (c) Posteriorly directed color mitral regurgitation jet visualized from parasternal long-axis view and (d) Posteriorly directed color mitral regurgitation jet visualized from apical four-chamber view.

Figure 4.

Mitral valve scallops evaluation using two-dimensional echocardiography. (a) Parasternal long-axis view showing A2, P2 scallops, mitral annulus dimensions, tenting height, and tenting area measurement. (b) Apical four-chamber view showing A3, P2, A1 scallops, mitral annulus dimensions, tenting height, and tenting area measurements. (c) Apical two-chamber view showing P3, A2, and P1. (d) Apical three-chamber view showing A2 and P2 and (e) Parasternal short-axis view at the mitral valve level showing A3, A3, A1, P3, P2, and P1.

Figure 5.

Mitral annulus components visualization using two-dimensional echocardiography short-axis views. (a) Parasternal short-axis mitral valve in normal conditions. (b) Parasternal short-axis papillary muscle in normal conditions. (c) Parasternal short-axis mitral valve in dilated cardiomyopathy with mitral valve apparatus posterior displacement and (d) Parasternal short-axis papillary muscle in dilated cardiomyopathy with papillary muscle posterior and lateral displacement. AML: anterior mitral leaflet, PML: posterior mitral leaflet, ALPM: anterolateral papillary muscle, PMPM: posteromedial papillary muscle.

Figure 6.

Mitral annulus velocity measurement by tissue Doppler echocardiography. (a) Interventricular septum velocity measurement and (b) Left ventricle anterolateral wall velocity measurement.

Figure 7.

Mitral valve scallops visualization by two-dimensional transesophageal echocardiography. (a) Mid-esophageal four-chamber view. (b) Mid-esophageal commissural view. (c) Mid-esophageal two-chamber view. (d) Mid-esophageal long-axis view. (e) Transgastric short-axis mitral valve. (f) Transgastric short-axis papillary muscle and (g) Transgastric long-axis view. A-L PM: anterolateral papillary muscle, P-M PM: posteromedial papillary muscle.

Figure 8.

Coaptation depth and length measured by two-dimensional transesophageal echocardiography. (a) Depth and (b) Length.

Figure 9.

Three-dimensional echocardiography mitral valve perspectives. (a) Atrial perspective, surgical view and (b) Ventricular perspective.

Figure 10.

Three-dimensional echocardiography mitral valve showing other structures. (a) Atrial perspective and (b) Ventricular perspective.

Figure 11.

Mitral annulus parameters evaluation by three-dimensional echocardiography (mitral valve quantification). (a) Three-dimensional annulus area. (b) Annulus perimeter. (c) Anteroposterior diameter. (d) Posteromedial-anterolateral diameter. (e) Commissural diameter. (f) Inter-trigonal distance. (g) Annulus height. (h) Non-planar angle and (i) Mitro-aortic angle.

Figure 12.

Mitral valve leaflet parameters evaluation by three-dimensional echocardiography (mitral valve quantification). (a) Anterior mitral leaflet area. (b) Posterior mitral leaflet area. (c) Anterior mitral leaflet length. (d) Posterior mitral leaflet length. (e) Anterior leaflet angle. (f) Posterior leaflet angle. (g) Closure line length. (h) Tenting height. (i) Tenting area and (j) Tenting volume.