The aim of the trial is to to quantify, in a randomized opened-labeled controlled trial the effect of sevelamer hydrochloride on the evolution of arterial stiffness parameters (pulse wave velocity and the augmentation index) in chronic haemodialysis patients and to correlate these parameters with arterial calcification assessed by a previous described radiological score of arterial calcification and echocardiographic parameters (left ventricular hypertrophy, LV dilatation, systolic and diastolic dysfunction).