PMC4199942_01
MSCT images of the three stenotic aortic valves in long-axis and short-axis views, and reconstructed aortic root models in Abaqus
nihms-586410-f0001.jpg
PMC4199942_01_nihms-586410-f0001.jpg
F1
The pre-procedural MSCT scans (Figure 1) showed heavy calcification on the non-coronary leaflet, and one large calcified spot on the interior of the left coronary sinus at the level between the ostium of the left main stem and the aortic annulus entering the myocardium. Case 2: Small and narrow left sinus of Valsalva was observed in a 65-year-old female patient with a tricuspid aortic valve and an annulus size of 23.7 mm (Figure 1). Case 3: Severe calcification was observed in aortic leaflets, ascending aorta, and left ventricular outflow tract (LVOT) of an 80-year-old female patient with a tricuspid aortic valve and an annulus size of 19.7 mm (Figure 1).
(a) Pre- and (b) post-deployment geometries of the aortic root of Case 1. (c) Full and (d) local views of the deformed the aortic root and balloon deployment indicates annulus tearing under the left coronary ostium due to dislodgement of calcification into the vulnerable part of the aortic sinus.
nihms-586410-f0004.jpg
PMC4199942_01_nihms-586410-f0004.jpg
F4
TAV stent with respect to the center of the aortic root. The TAV stent in the non-coronary sinus region was partially expanded, compared to fully expanded stent in the less calcified left coronary sinus region. The calcified spot on the interior of the left coronary sinus was displaced by the TAV stent (Figure 4), causing stress concentration at the bottom of the left coronary sinus (Figure 5) and consequently the aortic rupture.
Side (a) and top views (b) of the deformed native valve leaflets of Case 1 after the maximum stent deployment showed high stress at location of tearing. Stress (in kPa) contour plot was created for the aortic sinuses.
nihms-586410-f0005.jpg
PMC4199942_01_nihms-586410-f0005.jpg
F5
TAV stent with respect to the center of the aortic root. The TAV stent in the non-coronary sinus region was partially expanded, compared to fully expanded stent in the less calcified left coronary sinus region. The calcified spot on the interior of the left coronary sinus was displaced by the TAV stent (Figure 4), causing stress concentration at the bottom of the left coronary sinus (Figure 5) and consequently the aortic rupture.
Post-deployment geometries and stress (in kPa) contour plots of the aortic roots of ([a] and [c]) Case 2; and ([b] and [d]) Case 3 were utilized to evaluate the potential of complications such as aortic root rupture, coronary artery occlusion, and paravalvular leak. Stress (in kPa) contour plots ([c] and [d]) were created for the aortic sinuses.
nihms-586410-f0006.jpg
PMC4199942_01_nihms-586410-f0006.jpg
F6
Rupture of the aortic root at the bottom of the left coronary sinus started at approximately 88 % of the planned balloon injection volume (Figure 6a). Additionally, the deformed geometry showed that the native left coronary leaflet could cause possible coronary artery occlusion (Figure 6a).
Top view of the deformed native valve leaflets of Case 3 after the maximum stent deployment showed a small paravalvular leak.
nihms-586410-f0007.jpg
PMC4199942_01_nihms-586410-f0007.jpg
F7
A small paravalvular leak was observed at the bottom of the left coronary leaflet where a LVOT calcification spot was present (Figure 7).