title: The informational value of new qualitative indices of orthogonal ECG in the study of children with rheumatic heart disease.
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D004562:Electrocardiography; D006801:Humans; D008943:Mitral Valve / Q000503:physiopathology; D012214:Rheumatic Heart Disease / Q000175:diagnosis*