Changes And Significance Of Plasma Anp And Bnp Levels In Patients With Rheumatic Heart Disease And Chronic Atrial Fibrillation

Background: Patients with rheumatic heart disease usually suffer from chronic atrial fibrillation (CAF) simultaneously, which is a common phenomenon in cardiac surgery. CAF ties up with the progression, complications and prognosis of disease. Recent investigations indicated that the level of neuroendocrine hormone, such as atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP), plays an aid role in diagnosis and treatment of cardiovascular diseases. Studies have been accomplished extensively in the domain of heart failure, while researches in the field of arrhythmia are scarce yet.Objective: To investigate the clinical significance of dynamic changes of plasma ANP and BNP levels in patients with rheumatic heart disease and chronic atrial fibrillation. Besides these, imaginabale changes of artial fibrillation or other cardiac rhythm types should be kept an eye on at the same time.Methods: There were 30 patients admitted to the study. The preoperative NYHA cardiac function was measured by echocardiogram and hemodynamic parameters were monitored by Swan-Ganz floating catheter technique. The plasma ANP and BNP concentrations were determined before cardiac surgery, operation finish, 1day, 3days and 7days after operation. In addition, any cardiac rhythm changes must be watch out.Results: (1). There were positive correlations between NYHA and ANP or BNP (r =0.978, P﹤0.05; r =0.954, P﹤0.05; respectively), negative correlations between LVEF and ANP or BNP (r =-0.855, P﹤0.05; r =-0.803, P﹤0.05; respectively). (2). The preoperative level was the baseline, plasma ANP elevated markedly and acutely to a peak value just after operation (P <0.05),then it decreased continually on day 1, 3, 7 and gradually reached to the concentration before operation without significant difference, but was still higher than the level of SR control group (P﹤0.05). The peak level of BNP was on day 1, then it came down on 3days and 7days, but was higher than the level of before operation and SR group (both P﹤0.05) yet. (3). Cardioversion of atrial fibrillation appeared on 3 patients (10%) of the CAF group in the first month after operation, while atrial fibrillation relapse momently on two of them in the next two month. Retrospective analysis indicated that the preoperative plasma ANP and BNP concentrations of those 3 cases were lower markedly than the other 27 patients who maintained CAF (P﹤0.05). After operation, only the plasma ANP level had no remarkably changed on the epilogue of operation and the day 1 (P﹥0.05), while the data of ANP and BNP depressed significantly on the other periods of time (P﹤0.05). Furthermore, the plasma ANP and BNP levels of the 2 lucky men were descended significantly compared with the preoperative levels of themselves during follow-up on the third month. Postoperative provisional atrial fibrillation tachycardia occurred on 2 senile patients (20%) of the SR group in the forepart after operation (in 3 days). One of them renewed to normal without any intervention in half an hour, while another reverted to sinus rhythm in an hour after intravenous administration. There were no distinct discrepancies of the plasma ANP and BNP concentrations between the 2 cases and the other 8 sinus rhythm patients during the perioperative period (P﹥0.05).Conclusion: ANP play a important role in compensatory mechanism which prevent myocardium from the deterioration of cardiac function when patients suffering from chronic atrial fibrillation as well as their perioperative period. The plasma ANP concentrations can reflect the cardiac function and the state of the illness in patients undergoing cardiac valve replacement. The plasma ANP and BNP levels of CAF cases would be elevated due to the continuous injury from atrial fibrillation to heart function. A spot of them whose course of diseases are still mild and reversible might obtain the chance of cardioversion without intervention after operation in future, since the plasma ANP and BNP levels would reduce rapidly as soon as their harvest sinus rhythm. There are also a few part of sinus rhythm patients who undergo cardio operation might suffer provisional atrial fibrillation tachycardia in the forepart after operation. This study suggests that the preoperative values of atrial natriuretic peptide and brain natriuretic peptide in the blood are useful as a index for the cardioversion of chronic atrial fibrillation or the occurrence of provisional atrial fibrillation tachycardia after cardio operation.