The Effect of Frequency of Dialysis Session On Efficiency of Brain Natriuretic Peptide as Cardiac Biomarker Among Patient with End Stage Renal Disease

Background : There is overwhelming evidence about the importance of brain natriuretic peptide as a cardiac biomarker. However, the hemodynamic changes and associated abnormal body fluid homeostasis in patient with impaired renal function will add further complexity to the situation and may make the validity of brain natriuretic peptide as predictor of heart performance questionable. This prospective cross-sectional study tends to appraise the role of brain natriuretic peptide in determining left ventricular performance in patient with end stage renal disease treated by regular haemodialysis and its relation to the frequency of dialysis. Methods: the present study included ninety patients with end stage renal disease who attend Al-Hussein hospital in Thiqar governorate /Iraq for regular haemodialysis. The patients were further classified into 3 groups depending on the frequency of dialysis session. Ten ml of venous blood were taken from every patient to measure the plasma level of brain natriuretic peptide and creatinine. Glomerular filtration rate was estimated from plasma creatinine values utilizing Cockcroft-Gault equation. Left ventricular ejection fraction was determined by transthoracic two-dimensional echocardiography. Chi-square test used to assess the relationship between different studied variables. The relation considered significant when P value < 0.05. Results: There was a statistically significant negative relation between the plasma level of brain natriuretic peptide and left ventricular ejection fraction (P<0.001). The mean of plasma level of brain natriuretic peptide was significantly higher (P <0.001) in patients who underwent single dialysis each week when compared with patients who underwent three dialysis session each week. There was a strong negative association (P <0.001) between the renal function represented by the mean of glomerular filtration rate and level of brain natriuretic peptide in the plasma. Conclusion: Estimation of brain natriuretic peptide values in the plasma seems to be efficient in predicting left ventricular function among patients with end stage renal disease. However, utilizing brain natriuretic peptide measurement together with estimation of left ventricular ejection fraction seems to be necessary in these patients to avoid the bias in brain natriuretic peptide level which may contribute to other factors like volume status or impaired excretion of BNP rather than impaired left ventricular function.