Page 19 - Advanced echocardiography in characterization and management of patients with secondary mitral regurgitation

In the selection of patients for transcatheter mitral valve replacement, the dimensions and calcification of the mitral valve annulus should be assessed as well as the dimensions of the left ventricle and left ventricular outflow tract (LVOT). The mitral valve annulus has a characteristic saddle shape which may be difficult to conform for a tubular transcatheter expandable valve. Blanke et al.[16] proposed an MDCT-based simplified annulus description consisting of a D-shaped mitral annulus which is defined as being limited anteriorly by the intertrigonal distance, excluding the aortomitral continuity (Fig. 7). When measuring the mitral valve annulus according to the saddle shape, the area was significantly larger than when considering the D-shaped annulus (13.0 ± 3.0 cm2 versus 11.2 ± 2.7 cm2). In addition, the three-dimensional perimeter of the saddle-shaped annulus was significantly larger than the two-dimensional projected perimeter of the D-shaped annulus (136.0 ± 15.5 mm versus 128.2 ± 14.8 mm).
Figure 6: Multidetector row computed tomography to assess the anatomical suitability for transcatheter mitral valve annuloplasty. Panel a demonstrates a patient suitable for Cardioband. The left part shows the anchoring planning (arrow) in the mitral valve annulus. At the right is the distance measured between the anchoring and annulus (4.0 mm) and distance between anchoring and circumflex coronary artery (Cx, 7.6 mm). Panel b shows an example of a patient with unsuitable anatomy for Cardioband with massive mitral annulus calcification (arrows). In the left the anchoring would be in the calcified mitral valve annulus at the level of P1 (arrow). For indirect transcatheter mitral annuloplasty technique, the distance between the coronary sinus and the mitral annulus is relevant to efficiently reduce the size of the annulus. From three- dimensional volume rendering, the coronary sinus can be visualized coursing in this patient too high above the mitral annulus (line) as pointed out by the double arrowheads (panel C).
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