The Perioperative Changes And Clinical Signifcance Of Pro-brain Natriuretic Peptide Concentrations In Patients Undergoing Cardiac Valve Replacement

Brain natriuretic peptide (BNP) is a hormone secreted from the heart.BNP is synthesised and secreted as the form of pro-brain natriuretic peptide(proBNP),proBNP cleaves into a none physiological active fragment NT-proBNP and a physiological active fragment BNP. BNP promotes natriuresis and diuresis, acts as a vasodilator, and antagonizes the vasoconstrictor effects of the renin-angiotensin-aldosterone system. There is significant relationship between proBNP and cardiac function.The perioperative changes of serum proBNP concentrations are not clear in patients undergoing cardiac valve replacement.Objective To explore the perioperative changes of serum pro-brain natriuretic peptide (proBNP) concentrations in patients undergoing cardiac valve replacement , analysis the factors affecting proBNP,and evaluate the correlation between proBNP and cardiac function.Methods There were 48 patients admitted to the study, the serum proBNP concentrations were measured before cardiac surgery, 24 hours, 7days, 14 days, and 30 days after operation. The preoperative NYHAcardiac function and the left ventricle ejection fraction(LVEF) were measured by echocardiogram. There were 20 health populations in the control group.Results 1.The proBNP in patients with cardiac valve disease were marked higher than the healthy populations. 2. There was a positive correlation between NYHA and proBNP (r=0.71, P< 0.05), and there was a negative correlation between LVEF and proBNP(r=0.29, P>0.05). 3. There was no difference in LVEF ,but there was significant difference in proBNP in the different NYHA grade ,as well as patients with atrial fibrillation , digoxin needed, and diuretics needed. 5.The preoperative proBNP level was the baseline, it elevated sharply and acutely to a peak value 24 hours after operation, then the proBNP decreased 7 days later, but it was still higher than the concentration before operation, 14 days later it reached to the concentration before operation, 30 days later it was lower than preoperative proBNP level. 6.The proBNP was much higher in the patients with complications, and the proBNP was marked higher than preoperative proBNP at 30 days after operation.Conclusion l.The preoperative serum proBNP concentration can reflect the preoperative cardiac function in the patients undergoing cardiac valve replacement, the high proBNP level indicates the poor cardiac function. 2. ProBNP is more accurate to differentiate the cardiac status than LVEF. 3.The proBNP sharply elevated in the early time after operation, then gradually decreased in the late phase postoperation.