Evidence of accelerated atherosclerosis was studied from chest radiographs of 26 patients on maintenance hemodialysis. The aortic knob was observed for presence of and increase in calcified plaques. At the initiation of hemodialysis, the degree of aortic calcification was no different from that seen in the control group. After periods ranging from one and a half to eight years, the patients on hemodialysis showed a significantly greater amount of aortic calcification and a significantly higher rate of calcification. The degree of calcification correlated with the severity of cardiovascular disease as determined clinically. For patients on maintenance hemodialysis, close scrutiny of serial chest-radiographs may help to identify those who are at greater risk for life-threatening cardiovascular disease.