Atherosclerosis, also known as arteriosclerotic vascular disease (ASVD), is a medical condition characterized by the narrowing and hardening of arteries as a result of atheromatous plaque accumulating inside artery walls. Atherosclerosis is considered to be a more specific and advanced form of the related cardiovascular condition known as arteriosclerosis. However, arteriosclerosis only involves the thickening and stiffening of artery walls without the presence of excessive plaque buildup. It is this gradual accumulation of plaque that interferes with normal blood flow, which can eventually lead to blocked arteries and many other serious cardiovascular complications.
Atherosclerosis is caused when an artery's thin protective inner lining of cells, known as the endothelium, becomes damaged or inflamed allowing plaque to form on the arterial walls. The cells comprising the endothelium help maintain an artery's smoothness and elasticity, which enables healthy and efficient blood flow. When the endothelium is damaged, harmful LDL cholesterol is able to pass through and make contact with the arterial wall. In response, the body's immune system sends white blood cells, known as macrophages, in an attempt to eliminate the excess LDL cholesterol. However, over time, excessive amounts of both harmful LDL cholesterol and the usually helpful white blood cells accumulate, along with other minerals like calcium, as hardened plaque deposits along the walls of the arteries.
As time passes and the disease progresses, arteries become increasingly narrow, inflexible and obstructed as the amount of plaque steadily grows. According to the Duke Encylopedia of New Medicine, noticeable symptoms of atherosclerosis generally begin to appear once an artery becomes more than 70 percent obstructed. Information from WebMD also indicates that the diseases usually does not become this advanced in most people until at least middle to late adulthood. Common symptoms and complications of advanced atherosclerosis include angina (chest pain), blood clots, ischemia, strokes and heart attacks, as well as numerous other cardiovascular problems.
The primary causes of damage to the endothelium usually involve poor dietary habits, preexisting medical conditions and unhealthy lifestyles. In particular, high blood pressure (hypertension), high cholesterol, a high-fat diet, a lack of exercise, abdominal obesity and especially smoking play a significant role in the gradual development of both arteriosclerosis and atherosclerosis in people of all ages. The World Health Organization (WHO) estimates that almost 80 percent of coronary heart disease cases around the world involve poor diet, a sedentary lifestyle, and smoking. Other factors such as heavy alcohol or drug consumption, as well as high stress levels are also believed to contribute to one's risk of developing cardiovascular problems. Due to the overall prevalence of these risk factors within Western societies in general, coronary heart diseases associated with atherosclerosis are the primary cause of death in developed countries.
However, despite these grim facts, a 2010 National Institutes of Health report suggests that rates of cardiovascular disease have decreased over the past three decades in some parts of the world due to the scientific and technological advancements in modern medicine. Furthermore, most of the worst aspects of atherosclerosis and related conditions are largely preventable through relatively simple dietary and lifestyle changes.
