German researchers conducted a small trial and found that a urine test can detect coronary artery disease. The study author Dr. Constantin von zur Muehlen, a fellow in cardiology at University Hospital Freiberg reported that the test looks for fragments of the protein collagen, which plays a major role in blocking heart arteries. Muehlen also reported that high oncentrations of those fragments, called proteomes, in urine can signal atherosclerosis (hardening of the arteries), which can lead to a heart attack. The urine test was done for 67 people with symptoms of coronary artery disease. Two techniques to detect proteins, mass spectrometry and capillary electrophoresis, were used to find levels of 17 protein fragments that the researchers had identified as being associated with atherosclerosis. Muehlen said that the urine tests were found to be 84 percent accurate, when the results were compared to coronary angiography, an X-ray exam that is a standard method for diagnosing atherosclerosis, but a urine test to detect heart disease will not be developed quickly. The researchers again worked with a strain of mice genetically engineered to develop coronary artery disease as they age. Muehlen said that the mouse model found the pattern of proteomes becomes more heavily expressed. The patterns were extreme with the older animals. More animal studies are needed to fill in knowledge gaps. Unstable collagen is more chances to rupture, blocking an artery completely. Physicians at Brigham and Women's Hospital in Boston found in 2007, the presence of the protein albumin in urine of people with stable cardiovascular disease indicated an increased risk of death. Albumin is generally found in blood, but not in urine. The researchers reported that leakage of albumin into the urine indicates damage to the blood vessels of the kidney, which increases risk of cardiovascular death.