Cardiovascular disease (CVD) is the leading cause of mortality in patients with end-stage renal disease (ESRD), which means that it is important to find out risk factors of CVD in order to prevent or treat it. In recent years, there has been more and more recognition of a very high prevalence of CV calcification in the ESRD population. Many observational cohort studies have shown that CV calcification in these patients can predict mortality, CV mortality and morbidity. Electrolyte imbalance is easily found in the ESRD patients which may result in vessel calcification. Calcification leads to arterial stenosis and increasing arterial stiffness and then heart afterload, both contribute to the development of CVD. Besides, metabolic syndrome, insulin resistance, and dyslipidemia pave the way for a chronic, immune-mediated vascular inflammation and cardiovascular disease. These factors are prevalent in ESRD patients, which would also cause arterial stiffness. Arterial stiffness and stenosis would increase the risk of CV events and mortality. Aortic pulse wave velocity is strongly associated with the presence and extent of atherosclerosis and constitutes a forceful marker and predictor of cardiovascular risk. At the same time, high prevalence of peripheral artery occlusion disease (PAOD) should also be found while arterial stiffness and stenosis, which would increase the condition of infection and gangrene. Thus, life safety and quality would be influenced severely and early detection might prevent future amputation. Uremic patients also have a higher risk for metabolic syndrome. Therefore, more studies to evaluate the condition of arterial stiffness and PAOD, especially in HD patients, are needed for future management and preventions of CV related morbidity and mortality.

Inclusion Criteria:

1. Patients at National Taiwan University Hospital (NTUH)
2. patients who have received HD more than 3 months
3. Patients who sign the informed consents

Exclusion Criteria:

1. Patients who refuse to sign informed consents
2. Patients who refuse to draw additional blood for research

HD patients