Pulmonary capillary wedge pressure and natriuretic peptide levels in patients with sinus rhythm and severe left atrial enlargement following mitral valve surgery: early and late changes

INTRODUCTION Chronic mitral regurgitation is often accompanied by left atrial and ventricular remodeling and elevated natriuretic peptide levels. Our aim was to examine the relation between severe preoperative left atrial enlargement and changes in hemodynamics and natriuretic peptide levels after mitral valve surgery. METHODS A prospective study was conducted including 40 consecutive patients in sinus rhythm, with severe degenerative mitral regurgitation. N-terminal protype-B natriuretic peptide levels and hemodynamics were measured at predefined time points. An echocardiographic evaluation was performed the day before valve surgery and six months postoperatively. RESULTS Patients with left atrial volume index ≥60 mL/m(2), n=26, had higher baseline mean pulmonary capillary wedge pressure (17±9 mmHg vs 9±4 mmHg, p=0.010) and N-terminal protype-B natriuretic peptide (1326±2573 ng/L vs 233±221 ng/L, p=0.002) than patients with left atrial volume index <60 mL/m(2). The mean pulmonary capillary wedge pressure decreased to normal in patients with severe left atrial enlargement early after surgery, while it remained normal in patients without severe left atrial enlargement. The natriuretic peptide levels increased during the early postoperative period and decreased in both groups at 6-month follow-up. CONCLUSIONS A severe left atrial enlargement in patients with chronic degenerative mitral regurgitation and sinus rhythm indicates higher pulmonary capillary wedge pressure and natriuretic peptide levels than in those without. These findings may support early referral to surgery and may facilitate perioperative management. The potential reversibility of left atrial enlargement after surgery may be associated with postoperative reductions in pulmonary capillary wedge pressure and natriuretic peptide levels.