title: [Studies of postoperative cardiac function in secundum atrial septal defect by M-mode echocardiography].
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D004452:Echocardiography; D006344:Heart Septal Defects, Atrial / Q000503:physiopathology* / Q000601:surgery; D006801:Humans; D008875:Middle Aged; D009200:Myocardial Contraction; D011184:Postoperative Period