Rusted, Ian

This study attempts to bring into focus certain details which have not been described adequately in textbooks of anatomy. This information is now of considerable significance because of its role in the genesis and surgical treatment of mitral stenosis. Variations in the size and shape of the mitral valve are described, with particular reference to the fact that valve commissures, or junctional zones between the leaflets, occur in the normal valve. Measurements of commissures, chordae tendineae and valve leaflets are presented, with a discussion of the significance of some of these measurements.

Knowledge of the structural changes in the commissures, cusps, and chordae tendineae 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, mitral stenosis appeared to result principally from rigidity of the valvular leaflets. Measurements of the various components of the mitral valve in normal hearts have been given in a previous paper. In this communication, comparable measurements for these structures in 50 hearts with mitral stenosis are presented.