Surgical treatment on mitral valvular disease with giant left atrium. The effect of para-annular plication on left atrium.

Abstract
In severe mitral valvular disease with a giant left atrium, there occur such abnormal findings as the compression and bending of the basal portion of the posterior wall of the left ventricle accompanied by its paradoxical movement. Following mitral valve replacement in this group of patients, it was found that the strut of the artificial valve is apt to lean against the ventricular septum and the inflow stream of blood was directed toward outflow tract of the left ventricle, appearing to be obstructed by the ventricular septum. Here, we devised a new surgical method, para-annular plication, for patients with a giant left atrium. By this procedure, the compression and bending of the basal portion of the posterior wall of the left ventricle and the paradoxical movement were all relieved. The abnormal angle of the mitral valvular ring was corrected, the strut of the artificial valve was free from contact with the ventricular septum and the inflow stream of blood was directed toward the apex of the ventricle in usual manner. The overall operative result for giant left atrium has been markedly improved by this procedure.