Contributing Factors of Pulmonary Hypertension in Hemodialysis Patients.

Background: Pulmonary hypertension (PH) is a known complication of hemodialysis (HD) but its pathogenesis and etiology is not completely clear. The purpose of the current study is to determine the prevalence and possible causes of PH among hemodialysis patients.

Material and methods: Demographic, clinical and laboratory data of 40 patients referred to hemodialysis ward of Masih Daneshvari Hospital during 12 months were recorded. Detailed echocardiography was performed for each patient within 24 hours of hemodialysis. PH was defined as systolic pulmonary artery pressure (SPAP) above 35 mmHg.

Results: 12 of 40 HD patients had PH (prevalence = 30%). The hemodialysis vintage in PH group was longer than patients without PH (No PH group) . Also, left atrium size, right ventricle size, left ventricle end diastolic diameter (LVEDD) and left ventricular mass index (LV mass index) were significantly higher in PH group; but ejection fraction (EF) was lower than No PH group. Left ventricle diastolic dysfunction and pericardial effusion were significantly associated with PH. The crude mortality rate was relatively similar in PH group and No PH group.

Conclusion: PH is prevalent in HD patients with multifactorial etiology. Increased pulmonary capillary wedge pressure (PCWP) is a very important factor to induce PH in these patients; on the other hand, chronic volume overload and left ventricle systolic and diastolic dysfunction are some of the predominant causes of increased PCWP in this population.