Experimental investigation of the strength of the mitral valve in degenerative diseases
Abstract Renaissance of the reconstructive surgery of atrioventricular valves which has brought up lots of open questions makes this survey especially relevant. Due to the experimental tests our survey studies normal strength properties of mitral valve structures, various forms of mitral degenerative diseases and properties of repaired mitral valve structures.
We found that strength of the normal mitral valve leaflets is equal in all segments, whereas degenerative diseases are marked by local strength decrease of some segments.
During the experiment we showed criticality of decrease chordae strength properties, when under conditions of physiological stress chordae was fractured. We found that normal chordae have fourfold strength reserve, 74.2% fall of strength reserve causes chordae's fracture.
In groups of intact chordae in Barlow disease and fibroelastic deficiency dangerous decrease of strength was not found. In cases of Barlow disease maximum tension in intact chordae is 13.2% less then in normal chordae. In cases of fibroelastic deficiency maximum tension is 30.5% less then in normal chordae. Foregoing premises allow us to consider that decrease of intact chordae strength in cases of connective tissue diseases is not critical and therefore chordae could function in vivo after mitral valve repair.
Keywords:mitral valve, strength properties, degenerative pathologies
Clin. Experiment. Surg. Petrovsky J. 2015. № 3. Р. 18–24.
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