Perioperative Changes Of Plasma Brain Natriuretic Peptide Concentrations In Patients Undergoing Valve Replacement Surgery And Its Clinical Significance

Objectives:To investigate perioperative changes of plasma brain natriuretic peptide concentrations in patients undergoing valve replacement surgery,and study the clinical significance of perioperative changes of plasma brain natriuretic peptide concentrations preliminarily.Methods:Twenty patients following date-selectived valve replacement surgery were enrolled at admission for the test group.The preoperative cardiac function was classified according to NYHA classification.And we measured the UCG parameters of patients with heart valve disease.There were ten patients undergoing thoracic surgery in the control group.The plasma BNP concentrations was measured before surgery,1day,3 days,5days and 7days after the operation.At the same time,the interval duration of mechanical assissted ventilation,postoperative ICU custodial monitoring and hospitalization after surgery were recorded.And we analyzed the perioperative trend of plasma BNP.Correlation analysis was made between plasma concentrations of BNP and cardiac function,UCG parameters.And we study the relationship between perioperative brain natriuretic peptide concentrations and postoperative complications,clinical course.Results:1,The preoperative plasma BNP concentrations in the test group correlated positively with NYHA class (r=0.77,p<0.01)2,The LVEF in patients with NYHA IV were significantly lower than that in levelâ…¡andâ…¢group (p<0.05).The preoperative plasma BNP concentrations correlated positively with LVEDD(r=0.606,p<0.01),LVESD(r=0.688,p<0.01)and negatively with LVEF (r=-0.472,p<0.05),LVFS(r=-0.456,p<0.05)3,The plasma levels of BNP elevated markedly and reach peak value at lday after operation in test group,then BNP decreased but were still higher then the concentration before operation. The plasma levels of BNP just showed a short increase at 1day after operation in control group.4,The plasma BNP concentrations in patients with postoperative complications were significantly higher before and 1day after operation compared to those in patients without postoperative complications(p<0.05).The peak plasma BNP concentrations after operation in patients whose interval duration of mechanical assissted ventilation was more than 12h,were higher compared to those in patients whose interval duration of mechanical assissted ventilation was less than 12h(p<0.05).Conclusions:1,Preoperative plasma BNP levels can reflect cardiac function.With NYHA class increased,the plasma BNP concentrations increased gradually.The combination of BNP and echocardiography can increase the diagnostic accuracy of cardiac function.2,The plasma BNP sharply elevated in the early time after valve replacement surgery,then gradually decreased in the phase postoperation.Elevated preoperative and postoperative BNP levels have some effect in predicting postoperative complications and clinical course.