Mitral valve opening in the ovine heart.

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.

[1]  E L Yellin,et al.  Mechanisms of mitral valve motion during diastole. , 1981, The American journal of physiology.

[2]  R. E. Sturm,et al.  Experimental studies on the mechanisms of closure of cardiac valves with use of roentgen videodensitometry. , 1973, The American journal of cardiology.

[3]  E L Yellin,et al.  Temporal Relation of the First Heart Sound to Closure of the Mitral Valve , 1973, Circulation.

[4]  E D Wigle,et al.  Morphology of the Human Mitral Valve: I. Chordae Tendineae A New Classification , 1970, Circulation.

[5]  B. A. Carbello,et al.  Mitral valve disease. , 1993, Current problems in cardiology.

[6]  J. Mitchell,et al.  Instantaneous changes in the left ventricular lengths occurring in dogs during the cardiac cycle. , 1969, Federation proceedings.

[7]  M. Antunes Mitral Valve Repair , 1989 .

[8]  L. Irving,et al.  Motion of both mitral valve leaflets: a cineroentgenographic study in intact dogs. , 1975, Journal of applied physiology.

[9]  E D Wigle,et al.  Morphology of the Human Mitral Valve: II. The Valve Leaflets , 1970, Circulation.

[10]  A F Bolger,et al.  Three-dimensional regional dynamics of the normal mitral anulus during left ventricular ejection. , 1996, The Journal of thoracic and cardiovascular surgery.

[11]  G M Pohost,et al.  The Echocardiogram of the Anterior Leaflet of the Mitral Valve: Correlation with Hemodynamic and Cineroentgenographic Studies in Dogs , 1975, Circulation.

[12]  D. Bogen,et al.  Large animal model of ischemic mitral regurgitation. , 1994, The Annals of thoracic surgery.

[13]  R A Levine,et al.  The relationship of mitral annular shape to the diagnosis of mitral valve prolapse. , 1987, Circulation.

[14]  M A Niczyporuk,et al.  Automatic tracking and digitization of multiple radiopaque myocardial markers. , 1991, Computers and biomedical research, an international journal.

[15]  N B Ingels,et al.  Measurement of Midwall Myocardial Dynamics in Intact Man by Radiography of Surgically Implanted Markers , 1975, Circulation.

[16]  W. Spotnitz,et al.  Mechanism of mitral leaflet excursion. , 1995, The American journal of physiology.

[17]  P. Lynch,et al.  Movement of the mitral valve and its correlation with the first heart sound. Selective valvular visualization and high-speed cineradiography in intact dogs. , 1973, Investigative radiology.

[18]  J. Marshall,et al.  Three-dimensional echocardiographic reconstruction of the mitral valve, with implications for the diagnosis of mitral valve prolapse. , 1989, Circulation.

[19]  A. Bruschke,et al.  Comparison of rigid and flexible rings for annuloplasty of the porcine mitral valve. , 1990, Circulation.

[20]  R. Padiyar,et al.  Relation of mitral valve opening and closure to left atrial and ventricular pressures in the intact dog. , 1978, The American journal of physiology.

[21]  Reconsideration of echocardiographic standards for mitral valve prolapse: lack of association between leaflet displacement isolated to the apical four chamber view and independent echocardiographic evidence of abnormality. , 1988, Journal of the American College of Cardiology.

[22]  P. Salisbury,et al.  CHORDA TENDINEA TENSION. , 1963, The American journal of physiology.

[23]  Kinmonth Jb,et al.  THE MOVEMENTS OF THE ANNULUS OF THE MITRAL VALVE. , 1963 .

[24]  P. Fitzgerald,et al.  Mitral and aortic valve orifice area in normal subjects and in patients with congestive cardiomyopathy: determination by two dimensional echocardiography. , 1982, The American journal of cardiology.

[25]  W. Roberts,et al.  Mitral Valvular Disease: A Clinicopathologic Survey of the Conditions Causing the Mitral Valve To Function Abnormally , 1972 .

[26]  A. Schwarzkopf,et al.  A comparison of two analytical systems for 3-D reconstruction from biplane videoradiograms , 1988, Proceedings. Computers in Cardiology 1988.

[27]  M. Bourgeois,et al.  Size and motion of the mitral valve annulus in anesthetized intact dogs. , 1971, Journal of applied physiology.

[28]  M E Silverman,et al.  The mitral complex. Interaction of the anatomy, physiology, and pathology of the mitral annulus, mitral valve leaflets, chordae tendineae, and papillary muscles. , 1968, American heart journal.

[29]  C. Tei,et al.  Size and Motion of the Mitral Valve Annulus in Man: I. A Two‐dimensional Echocardiographic Method and Findings in Normal Subjects , 1981, Circulation.

[30]  W. Aronow,et al.  Mitral valve ring in normal vs dilated left ventricle. Cross-sectional echocardiographic study. , 1981, Chest.

[31]  R. F. Rushmer,et al.  Movements of the Mitral Valve , 1956, Circulation research.

[32]  C S Peskin,et al.  Fluid dynamics of the mitral valve: physiological aspects of a mathematical model. , 1982, The American journal of physiology.

[33]  R. Walmsley,et al.  Anatomy of human mitral valve in adult cadaver and comparative anatomy of the valve. , 1978, British heart journal.

[34]  B. Carabello,et al.  Valvular heart disease. , 1997, The New England journal of medicine.

[35]  Andreas Vesalius De humani corporis fabrica , 1964 .