Figure legends
Figure 1. Measurement of aorto-mitral (AM) angle in patient with native MV disease. Using the 2 orthogonal MV long-axis planes, the MV short-axis cut plane was determined to include the posterior saddle-shaped top and the lateral and medial commissures (Panel A-C). The AV long-axis cut plane was then obtained to include the aortic valve commissure between left- and non-coronary cusps (Panel D, green line) and the center of the right-coronary cusp. In this process, the MV short-axis cut plane was moved to obtain the aortic valve commissure and rotated to search for the bottom of the right-coronary cusp (= the center of the right-coronary cusp) in the AV long-axis cut plane (Panel E). The MV anterior leaflet insertion point on the AV long-axis cut plane was determined by visual identification using the cine loop. Finally, aortic annulus was obtained as the line that connected the mitral anterior leaflet insertion point with the bottom of the right-coronary cusp. 3D derived AM angle was measured as the obtuse angle between the aortic annulus and the MV short-axis (Panel F).
AV indicates aortic valve; LA, left atrium; LV, left ventricle; and MV, mitral valve.
Figure 2. Planimetry of the LVOT cross sectional area. Panel A shows the left ventricular long-axis plane. Transcatheter heart valve (green arrows) encroaches into LVOT. Panel B and C are the cross sectional short-axis planes with orientation indicated by red dotted lines [Panel A, (B) and (C)] at the valve stent distal edge and middle portion of the valve stent. The short-axis cut plane is moved manually up and down with rotation to search for the smallest area at each level. Importantly, care was taken that this area should not be moved from the plane perpendicular to the LV outflow long-axis. Panel D shows the short-axis image of the aortic annulus identified at the level of lowest aortic cusp hinge point. LVOT dimension and cross sectional area are measured at 3 levels (d1-d3 and a1-a3). In a patient with systolic anterior motion of mitral leaflet, who has the narrowest LVOT area at the level of leaflet tip, LVOT dimension and area at the valve stent distal edge are altered to these at the leaflet tip (Panel E-H). The LVOT area at the level of the leaflet tip is 0.3 cm2, surrounded by the anterior mitral leaflet (white arrowheads) and ventricular septum (yellow arrowheads).
Abbreviations as in Figure 1.
Calibration makers were shown on Figure A (for Figures A through D) and E (for Figures E through H).
Figure 3. Change in pressure gradient across LVOT in study patients.
LVOT indicates left ventricular outflow tract; and PG, pressure gradient.
Figure 4. The LVOT dimensions and cross sectional areas at 3 levels including the valve stent distal edge, middle portion of the valve stent, and aortic annulus. The LVOT dimension gradually became larger from the level at the valve stent distal edge to the aortic annulus, while the LVOT cross sectional area gradually became smaller from the level at the valve stent distal edge to the aortic annulus. Of note, there were 9 patients in whom LVOT area at the aortic annulus was not the minimum; 5 have the minimum area at the valve stent distal edge (red lines) and the others at the middle portion (green lines).
LVOT indicates left ventricular outflow tract.
*the most distal portion of the mitral valve stent that was closest to the LV apex
Figure 5. Relationships between LVOT cross sectional area at the valve stent distal edge versus LVESV, LVEF, and aorto-mitral angle. The correlations between the area and LVESV, LVEF, and aorto-mitral angle were moderate.
LVEF indicates left ventricular ejection fraction; LVESV, and left ventricular end-systolic volume.
Figure 6. Correlation between LVOT cross sectional area at the valve stent distal edge and the change in LVOT gradient.
∆PG indicates change in pressure gradient across LVOT.