Postoperative Evaluation of Mitral Valve Function in Ostium Primum Defect

Postoperative cardiovascular studies were carried out in eight patients with ostium primum defect and cleft mitral valve. Apical systolic murmurs were present in all pa-tients, but in seven of them no mitral regurgitation was detected by pulmonary wedge pressure and left ventricular angiography. Surgical repair of the cleft anterior leaflet without resection of subjacent chordae tendineae, as performed in these patients, usually results in a competent mitral valve. Postoperative angiograms showed persistence of the characteristic preoperative deformity of the medial border of the left ventricular outflow tract especially in systole. As illustrated in one of these patients, subaortic ob-struction occasionally complicates abnormalities of the atrioventricular valves. Additional Indexing Words: Endocardial cu'shion defect Subaortic T HAT apical systolic murmurs after repair of ostium primum atrial defects with cleft mitral valve indicate residual or surgically in-duced regurgitation has been suggested. Ras-telli and associates ' reported that most of their group of 53 patients had apical systolic mur-murs following surgical correction; residual in-competence of the mitral valve was presumed. In contrast, the hemodynamic studies carried out by Braunwald and Morrow2 in 18 patients, at intervals of 4 months to 52 years after sur-gery for incomplete persistent atrioventricular canal, identified only one with significant resi-dual mitral regurgitation. In the series of 28 pa-tients with incomplete, or partial, common atrioventricular canal studied by Lillehei and co-workers,3 mitral regurgitation was suspecte