Mitral valve posterior leaflet reconstruction using extracellular matrix: an acute porcine study

Area of Science:

• Cardiovascular Surgery
• Biomaterials Science
• Regenerative Medicine

Background:

• Mitral valve disease remains a significant clinical challenge, necessitating advanced reconstructive techniques.
• Small intestinal submucosal extracellular matrix (SIS-ECM) sheets offer a promising biomaterial for tissue engineering and repair.

Purpose of the Study:

• To evaluate the feasibility and efficacy of reconstructing the mitral valve posterior leaflet and subvalvular apparatus using a 2-ply SIS-ECM sheet.
• To characterize the functional and geometric outcomes of this novel reconstruction method in an acute porcine model.

Main Methods:

• Mitral valve posterior leaflet and subvalvular reconstruction was performed in an acute porcine model (n=7).
• Hemodynamic assessment using pressure catheter measurements evaluated mitral regurgitation, stenosis, and systolic anterior motion.
• Echocardiography and sonomicrometry were employed to assess leaflet mobility, geometry, and annular dimensions.

Main Results:

• The reconstructed mitral valve demonstrated full functionality, with no significant regurgitation (11 ± 2 mmHg vs 12 ± 2 mmHg) or stenosis (4.1 ± 2.3 mmHg vs 4.8 ± 2.3 mmHg).
• Echocardiography revealed increased coaptation length (8.7 ± 2.3 mm vs 6.0 ± 0.6 mm) and an atrial bend of the posterior leaflet.
• A ballooning effect of the SIS-ECM patch was observed at the posterior annular segment.

Conclusions:

• Reconstruction of the mitral valve posterior leaflet and subvalvular apparatus using a 2-ply SIS-ECM sheet is feasible in an acute porcine model.
• The reconstructed valve exhibited normal function without stenosis or regurgitation.
• The observed ballooning effect may indicate altered leaflet stress distribution, warranting further investigation.