They say people with high levels are more likely to suffer from severe heart disease. It is hoped the discovery could lead to a new test to diagnose patients who are most at risk. The scientists measured the levels of oxidised LDL in deposits which build up in the blood vessels called plaques. These plaques are thought to play a major role in causing heart disease by clogging up the arteries - a process called atherosclerosis. It was found that oxidised LDL was present at higher levels in the plaques of people with unstable angina than in those with the stable form of the condition.
Stable angina is chest pain that occurs during exertion.
People with unstable angina experience chest pain even while at rest. The researchers, from Osaka City University Medical School studied 135 patients who had various signs and symptoms of heart attack or angina. The patients with heart attack were studied within 24 hours of the onset of chest pain. Blood samples were taken from all patients when they were admitted to the hospital, and analysed for levels of oxidised LDL in the plasma. Cross sections For the second part of the study, researchers analysed sections of coronary arteries from 10 patients with stable angina and 23 with unstable angina.