Acute and stable coronary heart disease: different risk factors.

Coronary heart disease (CHD) continues to be a worldwide leading cause of death for both men and women. When coronary atherosclerosis progresses, there is deposition of plaque external to the lumen of the artery, thus the plaque may extend eccentrically and outward without compromising the lumen initially. As atherosclerosis worsens the plaque mass may later on bulge into the lumen and may therefore result in a haemodynamic obstruction and angina pectoris symptoms. Typically, angina pectoris develops when an atherosclerotic plaque obstructs at least 70% of the arterial lumen. Thus, stable angina pectoris is a condition in which there is regional myocardial ischaemia caused by inadequate coronary perfusion and is usually induced by increases in myocardial oxygen requirements. Chest pain that can be characterized as chronic stable angina typically is produced with physical exertion and relieved by rest and/or nitroglycerin. In contrast, chest pain that occurs at rest usually is indicative of unstable disease, such as acute coronary syndrome (ACS) that usually is caused by a coronary plaque rupture and subsequent intracoronary thrombosis formation.