T HIS PAPER was written first in 1960. At that time cases of the complete form of persistent common atrioventricular canal or endocardial cushion defect were regarded as consisting of an ostium primum defect of the atrial septum, a cleft in the anterior cusp of the mitral valve, a cleft in the septal cusp of the tricuspid valve, and an interventricular septal defect. Partial forms of the defect...

Knowledge of the structural changes in the commissures, cusps, and chordae tendineate is important to the understanding of the pathologic physiology of mitral stenosis and its surgical correction. Study of 70 hearts with mitral stenosis disclosed that a frequent cause of the obstruction was commissural fusion or shortening of the chordae tendineae or both. In a small percentage of hearts, mitra...

A spectrum of mitral valve disease was noted in 71 per cent of 163 specimens with transposition of the great arteries. At one end of the spectrum were hearts with normal mitral valve, except that the free margin of the anterior leaflet was shortened; at the other end were specimens with underdevelopment of the space between or behind the papillary muscles of the left ventricle. In additional ...

A third heart sound, followed by a diminuendo diastolic murmur, is generally accepted as characteristic of all but the most trivial grades of mitral incompetence. The genesis of these physical signs has remained controversial despite many human and animal studies. There are two main schools of thought concerning the origin ofthese sounds. The first or "extravalvar" school originated in Potain's...

CADIOVASCULAR sound may be divided into 2 categories,' namely, murmurs that result from turbulence in streams of blood flowing so rapidly that the critical Reynolds2' 3 number is exceeded and, heart sounds that represent vibrations resulting from abrupt changes in the velocity of blood movement. Since closure of the heart valves suddenly arrests or reverses the movement of blood, normal valve f...

M itral valve leaflets consist of thin, pliable, fibrous material. The two leaflets—anterior and posterior—open by unfolding against the ventricular wall and close by apposition when the pressure in the left ventricle becomes greater than that in the left atrium. Mitral stenosis occurs when the mitral valve leaflets become stiffened, calcified, and unable to open completely during diastole. Thi...

Eighteen percent of heart specimens with isolated ventricular septal defect also had a floppy mitral valve. There was no statistical difference in the incidence of floppy mitral valve in the three age groups considered (less than 1 year, 1 to 16 years and 17 to 91 years). In no patient was a floppy mitral valve considered to be the cause of death. Complications of floppy mitral valve (ruptured ...

A flow probe for direct measurement of blood flow of the mitral valve was devised. It was useful for acute experiment, particularly concerning pathophysiology of the mitral valve function. Insertion of the probe into the left atrium and fixation to the left atrial wall and thus to the mitral orifice were readily and satisfactorily performed without disturbance of blood flow and valvular functio...

The mitral valve comprises four structures: annulus fibrosus, cusp tissue, chordae tendineae, and papillary muscles. The annulus fibrosus is strong at the base of the aortic cusp, where it forms part of the aortic valve ring, and weak at the base of the mural cusp. From every part of the annulus cusp tissue hangs vertically downwards into the cavity of the left ventricle in the form of a short ...

Shone, Sellers, Anderson, Adams, Lillehei, and Edwards (1963) descri;bed a developmental deformity of the mitral valve characterized by insertion of the chordae tendineae into a single papillary muscle, producing a funnel-shaped valve which is to some degree stenotic. They employed the term 'parachute' first used by Edwards (1961), and noted an association with other leftsided cardiac deformiti...