title: Ball variance in a sutureless mitral valve prosthesis. A report of two cases and a clue to early diagnosis.
mesh_terms: D000328:Adult; D004417:Dyspnea / Q000209:etiology; D004562:Electrocardiography; D005260:Female; D006326:Heart Auscultation; D006350:Heart Valve Prosthesis / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008944:Mitral Valve Insufficiency / Q000601:surgery*