SERIAL EVALUATION OF ATRIAL FUNCTION BY DOPPLER-ECHOCARDIOGRAPHY AFTER THE MAZE PROCEDURE FOR CHRONIC ATRIAL-FIBRILLATION

The primary goal of the maze procedure is to prevent thromboembolism b y restoring atrial function. We used Doppler echocardiography to evalu ate the atrial function of patients who had undergone the maze procedu re for the treatment of chronic atrial fibrillation. Thirty-five patie nts who converted to sinus rhythm after the maze procedure were enroll ed in this study. Doppler echocardiography was performed in all patien ts in the early (mean, 19 days) and late (mean, 245 days) phases of th e postoperative period. Left and right atrial active contraction fract ions and left and right atrial storage fractions were calculated. The relationship between the pre-operative left atrial dimension and the l eft atrial active contraction fraction was evaluated in the late posto perative phase. The left atrial active contraction fraction was signif icantly increased in the late phase, but there was no change in the le ft atrial storage fraction. While the right atrial storage fraction wa s improved in the late phase, the right atrial active contraction frac tion was increased even in the early phase. In patients with non-rheum atic mitral valve disease, a significant negative correlation was obse rved between the pre-operative left atrial dimension and the left atri al active contraction fraction in the late postoperative phase (r=0.61 ; P<0.05). However, no correlation between these parameters was observ ed in patients with rheumatic mitral valve disease. Atrial function wa s improved after the maze procedure. Serial differences were observed between left and right atrial function during recovery. Thus, in patie nts with nonrheumatic mitral valve disease, the left atrial dimension prior to the maze procedure may be useful in predicting the atrial con tractile function postoperatively.