Mitral Valve Disease Complicated by Left-to-right Shunt at Atrial Level.

THE association of mitral stenosis with atrial septal defect (Lutembacher's syndrome 1) is well known but, when strict criteria of definition are applied, it is rare. For example, six, one, and no cases, respectively, were found in series of 2,000,` 500,4 and 400) patients undergoing commissurotomy for mi-tral stenosis, and only two cases exist in the pathologic files of the Mayo Clinic." Green and Lambert were aware of only one case in the literature with adequate preoperative documentation by clinical and hemodynamic methods. Mitral regurgitation and an interatrial communication are two of the components of persistent common atrioventricular canal.' We have been unable, however, to find a description of any adult patient with mitral regurgita-tion and a left-to-right shunt through a separate interatrial communication. This paper describes clinical and hemo-dynamic features in two patients who had in-teratrial communications causing left-to-right shunts associated with severe acquired mitral stenosis and with severe congenital mitral re-gurgitation. The diagnoses were made at cardiac catheterization and confirmed at surgery. It is our belief that in both the interatrial communication was due to incompetence of the foramen ovale secondary to dilatation of the left atrium.