| BackgroundSince physical exam findings, lab tests, electrocardiography and cheat X-rays are often nonspecific, and echocardiography is often not available in emergency, congestive heart failure (CHF), especially in the early stage, is often difficult to differentiate from other disease such as respiratory disease. Finding a blood test that could easily, rapidly and accurately aid in diagnosing CHF would be of great significance.B-type natriuretic peptide (BNP) is ,a neurohormone secreted mainly in the cardiac ventricles in response to volume expansion and pressure overload. Like atrial natriuretic peptide (ANP), BNP has effects of natriuresis, vasodilation, rennin inhibition and both central and peripheral sympathoinhibition. The release of BNP is directly proportional to left ventricular pressure and volume expansion. Unlike ANP, BNP has minimal presence in storage granules, the blood concentration of BNP is notaffected by exercises and emotion, only when BNP is synthesized can its blood concentration rise. Synthesis of BNP is regulated on the level of gene expression. BNP expression is induced with the rapid kinetics of an early response gene by an appropriate stimulus, leading to high turnover of BNP mRNA and synthesis of BNP in burst. Since BNP is synthesized in burst responding to cardiac dysfunction and it is mainly released by ventricle, BNP is suggested to be an early diagnostic criteria to heart failure.However, BNP tests are neither easy nor rapid in the early days. Recently a rapid radioimmunoassay for the detection of BNP (15 minutes) makes it possible to measure BNP bedside. Foreign scholars praised it highly as a "white count" in infective disease. The study of BNP is not performed commonly in domestic unit. There are many patients with rheumatic heart disease in our country. Weather BNP has identical value in those patients with rheumatic mitral stenosis in whom left ventricular pressure overload and volume expansion are not common. We compared the result of rapid bedside BNP assay with the latest diagnose in the patients with dyspnea to validate that BNP aids in early and rapidly diagnosing heart failure.ObjectiveTo investigate the value of rapid bedside BNP assay in early diagnosing heart failure.Patients and Methods132 patients (69 men and 63 women, mean age 65 years and deviation of 13 years, ranging from 22 to 90 years) with dyspnea presenting to urgent care or admission were recruited in Lishui city hospital from September 2002 to April 2003, some patients accompanied with cough, wheezing and edema etc. patients with chest trauma, cardiac tamponade, unstable angina, renal dysfunction or age under 18 years were excluded.Once a patient was identified as having dyspnea, consent was obtained and a blood sample was collected for BNP assay. Other data, including elements from the present and past history, the physical exam, other blood test results, chest X-ray, echocardiography and the patients medications were collected. The clinical diagnosis of congestive heart failure was adjudicated by two independent cardiologists, who were blinded to the results of the B-type natriuretic peptide assay.Confirmation of the diagnosis: (1) CHF: the diagnosis of CHF was based on generally accepted Framingham criteria with corroborative information including hospital course and results of further cardiac testing including echocardiography. The degree of heart failure was classified as I, II, III according to NYHA 2,3,4. Right ventricular dysfunction caused by cor pulmonale was included in heart failure. (2) Pulmonary disease: a chest X-ray and CT with signs, abnormal pulmonary function, a positive response to treatment with steroids or anti-biotics and normal heart function as seen by echocardiography, including chronic obstructive lung disease, pneumonia, lung cancer etc. (3) Other diseases, other problems that were not considered to be of cardiac or pulmonary etiology, such as anxiety gastroesophageal reflux disease,allergic reaction or cirrhosis.Measurement of BNP plasma... |
PDF Full Text Request