An 82 year-old lady with severe calcified aortic stenosis was referred for transcatheter aortic valve implantation to our institution.
From the right femoral artery, a 26 mm CoreValve (Medtronic Inc., Minneapolis, MN, USA) was advanced. However, during the deployment phase, the prosthetic valve was inadvertently pulled up above an optimal trans-annular position (panel A).
An aortogram showed moderate aortic regurgitation, due to paravalvular leak, with good visualization of both coronary arteries ( Video 1 ). In the following minutes patient developed marked ST depression (panel B2). TEE showed a subsequent rapid global deterioration of her ventricular function with hypotension.
Therefore, a new 26 mm CoreValve-in-CoreValve was implanted with resolution of clinical disturbances (panel C).
In order to understand how a valve grossly displaced toward the aorta could still maintain opening of the stenotic calcified leaflet without closing the coronary ostia, a silicon phantom model was used based on CT and aortogram images. A 26 mm CoreValve was deployed in a normal and supra annular position and subsequent analyzed using Micro CT (HMX-ST CT, X-TEK Systems Ltd, UK). The figure shows orthogonal 2D-scans and the 3D-reconstruction of a correct (panel D, E, F) and a high (panel G, H, I) valve deployment ( Fig. 1 ). When correctly positioned, the valve is anchored in the annulus and LV outflow tract with a preserved supra-annular valve function (panel F). Coronary flow obstruction can be produced by two mechanisms. One is the displacement of calcified leaflets into coronary ostia creating a mechanical obstruction to coronary flow; the second is the case depicted in our clinical vignette and demonstrated by the phantom model. An extremely high deployment still holds the native leaflets open without displacing them against the coronary ostia. However, the position of the prosthetic leaflets above the origin of coronary arteries may impede the diastolic filling of such vessels reducing flow during diastole (panel I). Dotted lines show the prosthetic valvular plane and the relationship with the origin of the coronary ostia (arrows).
