Ischemic Heart Disease and Agent Orange

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Ischemic Heart Disease

Heart disease is the leading cause of mortality in the Western World. The term “ischemic heart disease” refers to a condition whereby the heart itself is deprived of an adequate oxygen supply. It is usually caused by atherosclerosis; the narrowing of coronary arteries by the deposition of fatty material on the arterial walls. Ischemic heart disease is also referred to as coronary heart disease for this reason. The deposits are known as “atheroma” and they accumulate as irregular deposits in the large branches of the two main coronary arteries which supply the heart muscle itself with blood. Whilst the function of the heart is to pump oxygenated blood around the body, the heart tissue itself must be supplied with oxygenated blood to survive. As the fatty deposits accumulate, the arteries become narrowed and the amount of blood that can pass through them is reduced. If a coronary artery becomes blocked, the patient will suffer a heart attack and if the heart is deprived of oxygen for long, irreversible damage to the muscle will result. It is a common cause of congestive heart failure.

The risk of the condition increases with: age; a familial history of the disease (i.e. a genetic component); smoking; dietary factors (notably, a high cholesterol diet); diabetes; and high blood pressure.

Agent Orange

Agent Orange gained notoriety for its use as a defoliant by American forces during the Vietnam War. The product was actually a blend of herbicides which was sprayed on trees and vegetation to deny cover to the enemy, the Vietcong and the North Vietnamese Army. According to the US Department of Veteran’s Affairs, millions of gallons of the herbicide were sprayed during the conflict. Use of the product was controversial since it was rapidly linked to birth defects in children born to mother’s who were exposed to it during gestation. It has subsequently been acknowledged by the Department of Veteran’s Affairs to have been linked to at least 14 diseases, mainly cancers, for which sufferers may claim compensation. One of the illnesses that has been attributed to exposure to Agent Orange is an increased risk of ischemic heart disease, although this was only officially recognized at the end of October 2010, thirty-five years after the war ended.

The origins of Agent Orange were intended to be benign. They came out of a program conducted at the University of Chicago during World War II to boost plant growth. A compound was discovered that had strong defoliant properties (it was subsequently used as a garden weed killer). The research was passed on to the military authorities as a potentially useful agent. During the 1950s, it was discovered that when the compound was combined with a second agent, it resulted in very rapid defoliation of vegetation, by causing an uncontrolled growth spurt which is analogous to cancer in mammalian systems. This was the product used as a defoliant in Vietnam. The compounds were 2,4-dichlorophenoxyacetic acid and 2,4,5-trichlorophenoxyacetic acid, however, the tri-chloro compound was invariably contaminated with dioxins, a class of compound known to cause birth defects and an array of other illnesses. Dioxins are highly toxic and can cause reproductive and developmental problems, damage the immune system, interfere with hormones and also cause cancer. Dioxins can accumulate in fatty tissue and are persistent pollutant agents.


  1. Coronary Artery Disease:
  2. US Department of Veteran’s Affairs:
  3. US Department of Veteran’s Affairs:
  4. World Health Organization: