A review of the left atrio-ventricular valve anatomy is compared to a clinical oriented morphological study on 30 normal adult heart, preserved in formalin. The results will be presented in five separated sections: I. The cusps; II. The comissures; III. The chordae tendinae; IV. The papilary muscles; V. The valvar annulus. The present publication will deal with the cusps. The terms "left atrio-ventricular valve" and "cusps" are to be prefered to the more descriptive and traditional "mitral valve" and "leaflets". The anterior cusp, in continuity with the aortic annulus, and a group of posterior cusps, attached to the posterior left wall, are described. An ordinal numerical designation for the posterior cusps is proposed in order to facilitate ultrasonic and/or surgical references. The dimensions encountered for the cusps night, including the "rough" and "clear" zones are superposed to those from others authors, but those refered to the extensions, are slightly small, probably due to more fixed, natural curvature of the fixed hearts.
heart valves; heart valves; heart valves