Changes in Left Atrial Size and Cardiac Rhythm in Patients after Mitral Valve Surgery

Mitral valve disease often leads to dilatation of the left atrium and subsequent atrial fibrillation. We evaluated changes in sinus rhythm and left atrial size in a group of 77 patients (17 men, 60 women; average age, 60.7 years) who underwent mitral valve surgery (53 valve replacements and 24 valve repairs) between January 2000 and September 2001. The mean left atrial size was 56.2 mm before surgery (A), 52.6 mm on discharge from hospital (B) and 50.9 mm at one-year follow-up (C). The differences between A and B and A and C and that between B and C were statistically significant (P<0.001 and P<0.05, respectively) The valve replacement or repair also had a favourable effect on the restoration of sinus rhythm; the proportion of patients in sinus rhythm increased from 33% before surgery to 41% at one-year follow-up. In conclusion, surgical treatment of mitral valve disease results in a significant reduction of left atrial size and, in some patients, also in the restoration of sinus rhythm.