High mortality rates due to cardiovascular disease in end-stage renal disease patients been described by epidemiological and clinical studies. It accounts for approximately 50 percent of deaths in dialysis patients. Although controversial, this may be due to the presence of excess vascular calcification particularly in the form of extensive coronary artery calcification which can be observed even in very young dialysis patients. It was suggested that abnormalities of the right ventricular function in patients with end-stage renal disease were largely due to pulmonary hypertension which usually develops secondary to pulmonary artery calcifications.

Primary whose mechanisms are incompletely known, is another vascular disease entity recently described in chronic kidney disease particularly in patients undergoing haemodialysis. It corresponds to 5th subtype of World Symposium on Pulmonary Hypertension classification established in 2008 in Dana Point and updated in 2013 in Nice. Pulmonary hypertension is defined by Pulmonary arterial pressure mean ≥25 mm Hg at rest measured by right heart catheterization. Its pathophysiological mechanism is controversy maybe explained by vascular calcification, blood flow in arteriovenous fistula and fluid overload. Primary pulmonary hypertension is a major problem of haemodialysis patients because of its high prevalence, sometimes reaching 68% and by its significant morbidity and mortality.

Inclusion Criteria:

• 80 haemodialsis patients aged from 18 to 60 years old
• 80 haemodialysis patients are on regular haemodialysis for more than one year

Exclusion Criteria:

• All patients with a high probability of secondary pulmonary hypertension, those with the following history: chronic obstructive pulmonary disease, pulmonary embolism congenital heart disease, heart failure, Bilharziasis plus active HIV infection.

80 subjects undergoing haemodialysis for more than one year will be subjected to some diagnostic tools to detect and know the frequency of pulmonary hypertension(PH) among those patients.