 Pulse wave analysis Assessment of arterial stiffness will be performed, at baseline, at the end of 16 weeks of the trial and following 6 months, by a noninvasive technique using the commercially available SphygmoCor System AtCor Medical,LTD, Australia. All measurements will be performed by S.E while the patient is in the recombinant position at room temperature of 25oc. In brief, peripheral pressure waveforms will be recorded from the radial artery at the wrist, using applanation tonometry with a high-fidelity micromanometer Millar Instruments. When 20 sequential waveforms will be recorded, a validated 16-18 generalized transfer function will be applied to generate the corresponding central aortic pressure waveform. Augmentation index AIx and augmented pressure AP were derived by calculation, using pulse wave analysis technique. The merging point of the incident and the reflected wave the inflection point will be identified on the generated aortic pressure waveform. AP will be calculated as maximum systolic pressure minus pressure at the inflection point. AIx will be calculated as AP divided by pulse pressure and expressed as percentage. Higher values of AIx indicated increased wave reflection from the periphery or earlier return of the reflected wave as a result of increased pulse wave velocity attributable to increased arterial stiffness, and vice versa. Only high-quality recordings, defined as those with in-device quality index 80 as derived from an algorithm including average pulse height, pulse height variations, diastolic variations, and the maximum rate of rise of the peripheral waveform and the curves acceptable upon a visual inspection performed by one investigator, will be included in the analysis. All pulse wave measurements will be taken in the same sitting position, in a quiet, temperature controlled room 23 1C, after at least 15 minute resting period. 