TYPES OF CARDIOVASCULAR DISEASES: CORONARY HEART DISEASE
Of all the major types of CVD, CHD is the single greatest killer. In fact, this year well over 1,100,000 people will suffer from one of the major forms of coronary attack, and over 40 percent of them will die from one. Those of you raised on a weekly dose of TV doctor programs will recognize Code Blue as the term for a myocardial infarction (MI), or heart attack. However, you may not know exactly what a heart attack is. A heart attack involves a blockage of normal blood supply to an area of the heart. This condition is often brought on by a coronary thrombosis, or blood clot in the coronary artery, or through an atherosclerotic narrowing that becomes closed.When blood does not flow readily, there is a corresponding decrease in oxygen flow. If the heart blockage is extremely minor, the otherwise healthy heart will adapt over time by utilizing small unused or underused blood vessels to reroute needed blood through other areas. This system, known as collateral circulation, is a form of self-preservation that allows a damaged heart muscle to heal.When heart blockage is more severe, however, the body is unable to adapt on its own, and outside lifesaving support is critical. The hour following a heart attack is believed to be the most critical period because over 40 percent of heart attack victims die within this time. These sudden deaths are caused by cardiac arrest, usually resulting from ventricular fibrillation, or irregular, inefficient heartbeats.*6/277/5*
