Page 18 - Advanced echocardiography in characterization and management of patients with secondary mitral regurgitation

Chapter one. General introduction and outline of thesis
on to the fluoroscopy image with markers placed at the level of the transseptal puncture to intro- duce the guiding catheter (Panel c, arrow) and where the MitraClip device should be positioned (Panel c, arrow). Panels d and e display the simultaneous biplane color Doppler views of the mitral valve during the MitraClip device implantation which are oriented relative to the C-arm in Panel f. Panel g demonstrates the fusion image with fluoroscopy showing the markers of the trans- septal puncture and guiding catheter (arrow) and where the MitraClip device is placed (arrow).
Finally, two-dimensional and three-dimensional TEE are very important in the procedural guidance. Fluoroscopy does not have good soft-tissue resolution and needs the combination of echocardiography to guide the procedure. Current advances permit live fusion of echocardiography and fluoroscopy, facilitating the procedural guidance in key steps such as transseptal puncture and orientation of the device during the deployment of the device (Fig. 5).
Computed tomography
Multidetector row computed tomography (MDCT) is crucial to anticipate the feasibility of specific transcatheter mitral valve repair techniques. MDCT provides information on the mitral valve anatomy and geometry and its spatial relationship with surrounding structures [13,14]. When MDCT data are acquired along the entire cardiac cycle, the movement of the mitral valve leaflets can be characterized and the anatomical lesion causing the dysfunction can be identified. In addition, the narrowest three-dimensional anatomical vena contracta can be assessed by aligning the multiplanar reformation planes at the level of the tips of the mitral leaflets during systole [15].
MDCT is the imaging technique of choice to select patients and plan transcatheter therapies that target the mitral valve annulus or replace the valve. The key information that needs to be assessed with MDCT prior to transcatheter mitral annuloplasty includes the dimensions of the mitral valve annulus, the location of the coronary sinus and circumflex coronary artery relative to the mitral annulus and the presence of extensive mitral annulus calcifications, particularly at the anterolateral level (P1) where the first three anchors of the Cardioband device are implanted (Fig. 6). The size of the mitral valve annulus will determine the size of the annuloplasty device. The location of the coronary sinus relative to the mitral annulus is important when considering devices that indirectly cinch the mitral annulus (Carillon Mitral Contour System). In addition, the course of the circumflex coronary artery is important to predict the risk of impingement of this artery by the device (Fig. 6).
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