Mitral valve opening in the ovine heart

Autor: Neil B. Ingels, Matts Karlsson, Ann F. Bolger, Linda E. Foppiano, George T. Daughters, Masashi Komeda, Terrence Tye, D. Craig Miller, Julie R. Glasson
Rok vydání: 1998
Předmět:
Zdroj: American Journal of Physiology-Heart and Circulatory Physiology. 274:H552-H563
ISSN: 1522-1539
0363-6135
Popis: To study the three-dimensional size, shape, and motion of the mitral leaflets and annulus, we surgically attached radiopaque markers to sites on the mitral annulus and leaflets in seven sheep. After 8 days of recovery, the animals were sedated, and three-dimensional marker positions were measured by computer analysis of biplane videofluorograms (60/s). We found that the oval mitral annulus became most elliptical in middiastole. Both leaflets began to descend into the left ventricle (LV) during the rapid fall of LV pressure (LVP), before leaflet edge separation. The anterior leaflet exhibited a compound curvature in systole and maintained this shape during opening. The central cusp of the posterior leaflet was curved slightly concave to the LV during opening. Markers at the border of the “rough zone” were separated by 10 mm during systole. We conclude that coaptation occurs very near the leaflet edges, that the annulus and leaflets move toward their open positions during the rapid fall of LVP, and that leaflet edge separation, the last event in the opening sequence, occurs near the time of minimum LVP.
Databáze: OpenAIRE
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