Two Cases of Accessory Mitral Valve Tissue

(Department of Cardiovascular Surgery, Hakodate Central Hospital, Hakodate, Japan, Department of Cardiovascular Surgery, Hokkaido University Hospital*, Sapporo, Japan, and St. Lukes International Hospital**, Tokyo, Japan)

Masatoshi Motohashi Kimitaka Tasai Takehiro Kubota
Yoshiro Matsui* Kouhei Kawazoe**
We experienced 2 cases of accessory mitral valve tissue(AMVT). Case 1:A 56-year-old man was admitted with aortic regurgitation. Transthoracic and transesophageal echocardiography revealed AMVT with no left ventricular outflow tract obstruction. The patient underwent a successful aortic valvuloplasty. AMVT was carefully excised, because we suspected AMVT might be the cause of recurrent aortic regurgitation and left ventricular outflow tract obstruction with aging. Case 2:A 63-year-old woman was admitted with mitral regurgitation due to infective endocarditis. During medical treatment, transthoracic and transesophageal echocardiography revealed membranous structure in the left atrium uneffected by antibiotics. Mitral valvuloplasty and resection of membranous structure was performed. The membranous structure was not vegetation and had no relationship to mitral regurgitation. Pathological examination proved AMVT. To our knowledge, this is the first report of AMVT in left atrium in an adult.
  Jpn. J. Cardiovasc. Surg. 38:284-288(2009)