title: Left atrial function after Cox's maze operation concomitant with mitral valve operation.
abstract: BACKGROUND
  This study examined whether the atrial fibrillation that commonly occurs in patients with a mitral valve operation could be eliminated by a concomitant maze operation.
  
  
  METHODS
  Left atrial function after Cox's maze operation performed concomitantly with a mitral valve operation was evaluated in 10 patients ranging in age from 38 to 67 years (mean age, 54 years). Seven patients who had had coronary artery bypass grafting served as the control group. Using transthoracic echocardiography, the ratio between the peak speed of the early filling wave and that of the atrial contraction wave (A/E ratio) and the atrial filling fraction (AFF) were determined from transmitral flow measurements. These two indices have been considered to represent the contribution of left atrial active contraction to ventricular filling.
  
  
  RESULTS
  The A/E ratio and the AFF were significantly lower in the maze group (0.35 +/- 0.17 versus 0.97 +/- 0.28 [p < 0.01] and 17.6% +/- 8.8% versus 36.8% +/- 6.4% [p < 0.01], respectively). The A/E ratio and the AFF correlated inversely with age (r = -0.72, p < 0.05 and r = 0.76, p < 0.05, respectively) in the maze group. In an angiographic study, the mean left atrial maximal volume index in the maze group was approximately three times larger than that in the control group (117.5 +/- 24.3 mL/m2 versus 35.3 +/- 6.6 mL/m2 [p < 0.01]). The left atrial active emptying volume index was significantly smaller in patients in the maze group (7.2 +/- 2.5 mL/m2 versus 13.1 +/- 4.6 mL/m2 [p < 0.01]).
  
  
  CONCLUSIONS
  After the maze procedure performed concomitantly with a mitral valve operation in patients with a dilated left atrium, left atrial contraction is detectable but incomplete in the elderly.
authors.affiliation: Department of Thoracic Surgery, Yokkaichi Municipal Hospital, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Itoh
authors.forename: H
authors.initials: H
authors.lastname: Okamoto
authors.forename: T
authors.initials: T
authors.lastname: Nimi
authors.forename: S
authors.initials: S
authors.lastname: Morita
authors.forename: M
authors.initials: M
authors.lastname: Sawazaki
authors.forename: Y
authors.initials: Y
authors.lastname: Ogawa
authors.forename: T
authors.initials: T
authors.lastname: Asakura
authors.forename: K
authors.initials: K
authors.lastname: Yasuura
authors.forename: T
authors.initials: T
authors.lastname: Abe
authors.forename: M
authors.initials: M
authors.lastname: Murase
mesh_terms: D000328:Adult; D000368:Aged; D001281:Atrial Fibrillation / Q000209:etiology / Q000503:physiopathology* / Q000601:surgery*; D016279:Atrial Function, Left; D006328:Cardiac Catheterization; D015150:Echocardiography, Doppler; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008944:Mitral Valve Insufficiency / Q000150:complications / Q000503:physiopathology* / Q000601:surgery*; D008946:Mitral Valve Stenosis / Q000150:complications / Q000503:physiopathology* / Q000601:surgery*; D009200:Myocardial Contraction