The Effect of Aortic Valve Replacement on Plasma B-Type Natriuretic Peptide in Patients with Severe Aortic Stenosis — One Year Follow-Up

BACKGROUND: B-type natriuretic peptide (BNP) is synthesized in cardiac tissue in response to increased wall stress and myocardial hypertrophy. AIMS: In patients with severe aortic stenosis (AS) we examined the effect of aortic valve replacement (AVR) on plasma BNP and association between BNP and left ventricular mass index (LVMI) preoperatively and in the reverse-remodeling phase twelve months postoperatively. We also examined the correlation between BNP and NYHA-class and between BNP and age. METHODS AND RESULTS: Plasma BNP analyses and echocardiographic measurements were performed preoperatively, before discharge after AVR, and at twelve months in twenty-two patients. BNP was additionally measured at six months. Preoperatively, BNP was 283+/-45 pg/ml (mean+/-SEM). Following an immediate postoperative increase (441+/-38 pg/ml), BNP values decreased towards normal values at six and twelve months (139+/-25 and 130+/-18 pg/ml, respectively). LVMI was 206.5+/-15.8 g/m(2) preoperatively and decreased to 119.7+/-7.2 g/m(2) at twelve months with a correlation between LVMI and BNP preoperatively only (r=0.45, p<0.05). There was no correlation between BNP and NYHA-class, whereas BNP correlated to age both pre- and post-operatively. CONCLUSION: We report an increase in plasma BNP in patients with AS. Following a further transient increase postoperatively, BNP levels decreased at six and twelve months after AVR. BNP correlated with LVMI preoperatively, and with age both preoperatively and at twelve months.