Figure 4
High-Resolution CMR - Stent-Valves. Photograph (left side) of the Edwards SAPIEN™ (top) and the Medtronic CoreValve® bioprostheses (bottom) with corresponding single coronal slices from high-resolution T1-weigthed 3D FLASH sequences (right side). While RF signal attenuation within the stent was similar for both stent-valves, the Medtronic CoreValve® prosthesis could be depicted in greater detail, even showing the eyelets (arrows) at the outflow tract of the stent. Such a subtle and constrained artifact may potentially be used to indicate orientation before and during valve deployment. This may become relevant in the future of TAVI when rotational orientation with regards to the coronary ostia has to be respected with new devices such as the self-expandable, Acurate RP™ porcine bioprosthesis (Symetis S.A., Lausanne, Switzerland). Likewise, the Edwards SAPIEN™ prosthesis exhibits a somewhat inhomogeneous artifact (arrows) caused by the joint insertion of two adjacent leaflets at the stent-frame, thereby resembling one of the three commissures.