Coronary heart disease (CHD) refers to diseases of the heart and the vessels running to and from it; they are the leading cause of death in the world. Also known as ischaemic heart disease (IHD), CHD it is almost always a consequence of atherosclerosis: a build-up of cholesterol and other material in the walls of our arteries (tubes that carry blood and oxygen to the heart). The build-up can cause heart attack and block access to the brain, leading to stroke – another top killer.
Ischaemic heart disease is not really the disease itself. Rather, it is the term used to cover the clinical manifestations of coronary heart disease such as heart attacks and angina. Ischemia describes insufficient oxygen supply to the heart muscle. Lack of oxygen can cause discomfort in the chest, such as a tightness or squeezing known as angina. This is most often brought on by exercise but is more serious when it happens at rest. Persistence of angina over time, particularly at rest, can lead to death of some heart muscle. This is called an acute coronary syndrome, myocardial infarction or colloquially, a heart attack..
The rise of coronary heart disease has been traced to the 1940's in western Europe and the 1920's in the US, reaching its peak in the 1970's in western Europe and the 1960's in the US. It has been associated by medical doctors with frequent consumption of meat, refined foods, and artificial ingredients; also with certain inflammatory diseases caused by infections, which may in turn cause inflammation of the arteries and plaque build up.
Coronary heart disease (CHD) kills about two million people every year in the West, more people than any other disease or illness. Death rates in most industrialized countries are stationary or rising. According to a 1991 UK report, an estimated 480 Britons die every day from coronary heart disease, the leading cause of death in the country. About 15 times as many people have coronary heart disease as are killed by it; in the USA 13 million people had it in 1996, of whom 500,000 died of a heart attack. In 2014, 20,173 people died from ischaemic heart disease.
In developing countries such as Malaysia, Singapore and Sri Lanka, the incidence has reached very high levels. In some developing countries, CHD has already emerged as a prominent public health problem afflicting especially men in the prime of life when their productivity and social and family responsibilities are greatest. In others, CHD poses a serious potential threat to health, and the probability is that, unless this threat can be averted or contained, it will soon reach proportions approaching those of the industrial countries.
63% of coronary heart disease has an inherited component. The gene ApoE 4 increases the absorption of cholesterol from food. This is obviously an advantage in times of famine and with some of the more irregular diets of human ancestors. The level of homocysteine (a protein that affects blood clotting) is also genetically determined, and can be countered with folic acid to reduce the clotting risk.
A low-fat mainly vegetarian diet could prevent 1.25 million heart attacks per year in the USA.