The Correlation Study Of B-type Natriuretic Peptide And Aortic Stenosis With Different Types Heart Failure

Background: The heart failure caused by aortic stenosis (AS) has a highmorbidity and mortality. In recent years the plasma b-type natriuretic peptide (BNP),the only diagnostic biomarker for heart failure, have been widely used in the clinicalpractices.Objective:To observe the correlation between the degree of cardiac structure andfunction impaired and the level of BNP in AS patients and to discuss the diagnosticvalue of BNP for heart failure in AS patients. Further, the value of identify heartfailurepreserved ejection fraction (HFPEF) and heart failure reduced ejection fraction(HFREF) by the level of BNP is discussed.Methods: A total of82cases who were admitted in the CardiovascularDepartment or examined in the Center of Health Examination in the First AffiliatedHospital of Dalian Medical University from2012January to2013January wereenrolled for the study.62AS patients were divided into3groups: isolated AS groupwith20patients having isolated AS, HFPEF with AS gruop with20patients andHFREF with AS gruop with22patients. Twenty individuals who were examined in theCenter of Health Examination in the same hospital were enrolled as the control group.Everyone was were examined by echocardiography and measured BNP by doubleantibody sandwich method. After statistics processing, compare the differences amongfour groups. Receiver operating characteristic curve (ROC) was used to evaluate thediagnostic value of BNP for heart failure in AS patients and find the cutoff value ofplasma BNP in diagnosing heart failure in AS patients. Further, the ROC was used toidentify heart failure preserved ejection fraction (HFPEF) and heart hailure reducedejection fraction(HFREF) by the level of BNP.Results:1. Compared with control group, the BNP levels is higher in all AS group (P < 0.05). The BNP levels in HFREF with AS gruop is the highest，and HFPEF with ASgruop takes the second place. Compared with isolated AS group, the BNP levels ishigher in all AS with heart failure group (P <0.05), and there were statisticaldifferences between four groups(P <0.05).2.1The area under the ROC curve for the BNP level as a diagnostic indicator forheart failure in AS patients was0.952, Asymptotic95%Confidence Interval (95%CI)was0.602～0.849(P＜0.01), suggests that the BNP levels has a high diagnostic valuefor heart failure in the AS patients.2.2The cut off value for BNP level as a diagnostic indicator for heart failure inAS patients was700pg/ml. Their Sensitivity, Specificity, Positive predictive value andNegative predictive value value were85.7%,90.0%,94.7%,75.0%respectively.2.3The heart failure preserved ejection fraction (HFPEF) and heart failure reducedejection fraction (HFREF) can be identified by the level of BNP1200pg/ml.3. The BNP level is positively associated with the degree of heart failure. Thehigher of HYHA grading, the higher of BNP level. In the study, BNP level in HYHAIV group is lowest and in HYHA I group is hightest.4. The BNP level is positively associated with the degree of aortic valve stenosis.The more serious of aortic valve stenosis, the higher of BNP level. In the study, seriousaortic valve stenosis group is significantly higher than mild and moderate group.Conclusion:1. The plasma BNP levels can be a good response of cardiac damage in ASpatients.2. The BNP level in AS with HFREF is significantly higher than AS with HFPEFpatients, BNP can distinguish different types of heart failurei in AS patients.3. The BNP levels has a high diagnostic value for heart failure in the AS patientsand can be used in screening and follow-up.