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Updated: May 22, 2026
09:09
In Silico Clinical Trials for Cardiovascular Disease
Published on: May 27, 2022
Smooth muscle in the human mitral valve: extent and implications for dynamic modelling
Ivar S Nordrum1, Bjørn Skallerud
1Department of Laboratory Medicine, Children's and Women's Health, Norwegian University of Science and Technology, Trondheim, Norway. ivar.nordrum@ntnu.no
Summary
Human mitral valves contain smooth muscle bundles, particularly in the anterior leaflet, extending from the annulus towards the leaflet rim. This finding suggests a potential role for muscular capabilities in mitral valve function.
Area of Science:
- Cardiovascular Biology
- Cardiac Anatomy
- Histology
Background:
- The mitral valve's dynamic and contractile capabilities are increasingly recognized.
- Limited research has explored the presence of muscle tissue within the mitral valve itself.
Purpose of the Study:
- To investigate the presence, architecture, and phenotype of muscle tissue in the human mitral valve.
- To characterize the distribution and orientation of smooth muscle within mitral valve leaflets.
Main Methods:
- Human mitral valves (n=12) were dissected into strips.
- Histological sectioning and immunophenotyping were performed.
- Microscopic examination of stained tissue sections was conducted.
Main Results:
- Smooth muscle bundles were identified on the atrial side of mitral valve leaflets.
- The anterior leaflet exhibited significantly more smooth muscle than the posterior leaflet.
- Muscle bundles extended up to two-thirds of the leaflet length from the annulus, with decreasing thickness and density distally.
Conclusions:
- The human mitral valve, especially the anterior leaflet, possesses a distinct smooth muscle meshwork.
- This muscular structure is located on the atrial surface, near the annulus.
- The findings support the concept of intrinsic contractile capabilities within the mitral valve leaflets.
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