Hemodynamic data before, immediately after, and 4 weeks after implantation.

<p>Right ventricular systolic pressure (A), pulmonary artery systolic pressure (B), and peak-peak transvalvular pressure gradient (C) were assessed. vs. before group, *P<0.05, **P<0.01.</p

Valved stent implantation process (representative images).

<p><b>A</b> Imaging of the pulmonary valve was performed to measure the pulmonary valve radius and location. <b>B</b> After the valved stent was advanced to the pulmonary valve via the 22F sheath, a right ventricular angiography was performed to confirm that the valved stent was at the optimal position. <b>C</b> The valved stent was fully balloon-expanded. <b>D</b> A pulmonary angiography showing correct position of the valved stent in the pulmonary position in an sheep model. No regurgitation was assessed.</p

Echocardiography 4 weeks after implantation from a representative. sheep with a 20 mm PTPV.

<p><b>A</b> The two parallel lines of echo enhancement showed appropriate position and open shape of the stent (white arrow). <b>B</b> Color Doppler ultrasonography revealed no regurgitation or paravalvular leakage. <b>C</b> Doppler ultrasonography revealed the peak-peak transvalvular pressure gradient of the stented valve was 13 mmHg. <b>D</b> The motion distance of the valve cusp was 0.781 cm measured by Doppler ultrasonography, meaning normal function of the valve leaflet.</p

Electron microscopic images of the ePTFE leaflets explanted from a sheep 4 weeks after surgery.

<p><b>A</b> Scanning electron microscopic appearance of the outflow side of a ePTFE valve cusp showing polyporous structure of ePTFE and no obvious cell or tissue attachment (×5000). <b>B</b> Transmission electron microscopic appearance of the outflow side of a ePTFE valve cusp showing polyporous structure of ePTFE and no obvious cell or tissue infiltration. (×1500).</p

The 3D reconstruction CT image 4 weeks after implantation from a representative sheep with a 20 mm PTPV.

<p>The image demonstrated orthotopic position and no deformation of the stent (white arrow).</p

Histologic images of the ePTFE valve leaflets explanted from a sheep 4 weeks after surgery.

<p><b>A</b> The surface of ePTFE leaflet was smooth, without obvious cell or tissue infiltration. The ePTFE membrane showed multilayered structure.(HE×400). <b>B</b> The surface of ePTFE on the sealing cuff revealed fibrous overgrowth, which attached loosely to the ePTFE membrane which itself had no obvious cell or tissue infiltration.(HE×200).</p

Views of the polymeric prosthetic pulmonary valve.

<p>Top view, bottom view, and side view of the balloon-expandable cobalt-chromium alloystent (length, 24.6 mm; diameter, 20 mm) containing a 3-leaflet ePTFE valve.</p

Gross morphology of the ePTFE valved stent explanted from a sheep 4 weeks after surgery.

<p><b>A</b> The native pulmonary valve can be seen (arrow), confirming the correct position of the valved stent. <b>B</b> The outflow side of ePTFE valved stent showed the leaflets were thin without significant tissue deposits. <b>C</b> The inflow side of ePTFE valved stent showed slight fibrous overgrowth at the bottom of the leaflets, in the commissural areas and on the sealing cuff.</p

Views of the surgical approach.

<p><b>A</b> The thoracic cavity was opened via the right anterolateral thoracotomy at the fourth intercostal space, and the right ventricular anterior wall and apex were exposed. Black arrow showing the left anterior descending coronary artery (LAD). White arrow showing the right atrioventricular groove. <b>B</b> Two felt strip-buttressed purse-string sutures were placed at the right ventricular apex almost 10 mm far away from LAD (white arrow).</p

Views of the delivery system.

<p><b>A</b>. Views of the 22F introducer sheath set (white arrow), the auxiliary short sheath (black arrow), and the 20 mm×3 cm high-pressure balloon catheter (double black arrows). <b>B</b> The valved stent was crimped symmetrically onto the inflatable portion of a balloon catheter. <b>C</b> Placement of valved stent into the auxiliary short sheath.</p