Decreased plasma brain natriuretic peptide levels after a successful maze procedure

Previous reports indicate that plasma levels of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) increase in atrial fibrillation (AF), but decrease after successful direct current (DC) cardioversion. Although the maze procedure is the only curative therapy for AF, the effects on atrial and left ventricular function remain unclear. The study aim was to determine whether plasma ANP and BNP levels decrease after the maze procedure in patients with mitral valve disease.

Twenty-seven patients either with (n = 23) or without (n = 4) AF underwent mitral valve surgery; of these patients, 13 underwent a maze procedure for chronic AF. Blood samples and echocardiographic data were obtained before and at one year after surgery.

Ten patients with AF achieved sinus rhythm (SR) or junctional rhythm after the maze procedure. In patients subjected to mitral valve surgery, mean plasma levels of ANP and BNP were 59.8 +/- 11.9 and 139.2 +/- 53.7 pg/ml, respectively. ANP and BNP plasma levels fell significantly after surgery (to 32.1 +/- 4.1 and 46.7 +/- 10.2 pg/ml, respectively; p = 0.04 and p = 0.004). In patients with successful maze procedure, plasma levels of BNP and left ventricular end-diastolic dimension (LVDd) were significantly decreased by 35.7% and 82.7% compared with preoperative values (BNP, 35.7 +/- 4.9% for SR versus 83.4 +/- 9.6% for AF, p = 0.008; LVDd, 82.7 +/- 3.7% for SR versus 97.0 +/- 3.2% for AF, p = 0.0159).

A successful maze procedure significantly decreased LVDd and plasma levels of BNP after surgery. These results show that the maze procedure is effective in improving left ventricular diastolic dysfunction for a mid-term period in patients with mitral valve disease.