The Persistent Ostium Primum Atrial Septal Defect

Abstract

Five patients with an ostium primum type of atrial septal defect were studied by clinical and laboratory methods and the diagnosis was verified either at the time of open-heart surgery and/or at autopsy. The atrioventricular valves formed the floor of the defect and were deformed in 4 of the 5 patients. Mitral insufficiency was present as a result of this valvular deformity in these four patients. This valvular deformity resulted in a high pitched blowing systolic murmur, audible over the apical and lower left sternal areas, and left axis deviation and indications of left ventricular hypertrophy, determined by electrocardiography. The deformity of the mitral valve is considered to be the basis for these variations from the typical findings found in the patient with an ostium secundum type of atrial septal defect and make the differential diagnosis of the persistent ostium primum possible under these circumstances.