Pulmonary Hypertension among Patients on Hemodialysis

Abstract

P ulmonary hypertension in end-stage renal disease patients is associated with significantly increased morbidity and mortality. The prevalence of pulmonary hypertension in dialysis patients is relatively high and varies in different studies from 17% to 49.53% and in this study was 35 % depending on the mode of dialysis and other selection factors, such as the presence of other cardiovascular comorbidities. The etiopathogenic mechanisms that have been studied in relatively small studies mainly include arteriovenous fistula-induced increased cardiac output, which cannot be accomodated by, the spacious under normal conditions pulmonary circulation. Additionally, pulmonary vessels show signs of endothelial dysfunction, dysregulation of vascular tone due to an imbalance in vasoactive substances, and local as well as systemic inflammation. It is also believed that microbubbles escaping from the dialysis circuit can trigger vasoconstriction and vascular sclerosis. The determinants of pulmonary hypertension were mainly enlarged left atrial diameter, low urea reduction ratio and lack of vitamin D analogue use. PH in dialysis patients is clinically important and affects severely the morbidity and mortality in this group of patients. Further research of this devastating disorder is warranted in this group of patients. Estimation and follow up of PAP using Doppler echocardiography may be indicated in all patients with ESRD undergoing hemodialysis via AVF.