Coronary artery disease (CAD; also atherosclerotic heart disease) is the end result of the accumulation of atheromatous plaques within the walls of the coronary arteries that supply the myocardium (the muscle of the heart) with oxygen and nutrients. It is sometimes also called coronary heart disease (CHD). Although CAD is the most common cause of CHD, it is not the only one.
CAD is the leading cause of death worldwide. While the symptoms and signs of coronary artery disease are noted in the advanced state of disease, most individuals with coronary artery disease show no evidence of disease for decades as the disease progresses before the first onset of symptoms, often a "sudden" heart attack, finally arises. After decades of progression, some of these atheromatous plaques may rupture and (along with the activation of the blood clotting system) start limiting blood flow to the heart muscle. The disease is the most common cause of sudden death, and is also the most common reason for death of men and women over 20 years of age. According to present trends in the United States, half of healthy 40-year-old males will develop CAD in the future, and one in three healthy 40-year-old women. According to the Guinness Book of Records, Northern Ireland is the country with the most occurrences of CAD. By contrast, the Maasai of Africa have almost no heart disease.
As the degree of coronary artery disease progresses, there may be near-complete obstruction of the lumen of the coronary artery, severely restricting the flow of oxygen-carrying blood to the myocardium. Individuals with this degree of coronary artery disease typically have suffered from one or more myocardial infarctions (heart attacks), and may have signs and symptoms of chronic coronary ischemia, including symptoms of angina at rest and flash pulmonary edema.
A distinction should be made between myocardial ischemia and myocardial infarction. Ischemia means that the amount of blood supplied to the tissue is inadequate to supply the needs of the tissue. When the myocardium becomes ischemic, it does not function optimally. When large areas of the myocardium becomes ischemic, there can be impairment in the relaxation and contraction of the myocardium. If the blood flow to the tissue is improved, myocardial ischemia can be reversed. Infarction means that the tissue has undergone irreversible death due to lack of sufficient oxygen-rich blood.
An individual may develop a rupture of an atheromatous plaque at any stage of the spectrum of coronary artery disease. The acute rupture of a plaque may lead to an acute myocardial infarction (heart attack).
This text uses material from Wikipedia
licensed under CC BY-SA
A second US patient has been infected with a superbug that is highly resistant to last-resort antibiotics, scientists said Monday.
Sometimes in health care, simple activities can be just as effective as the latest technology.
(HealthDay)—Babies who learn to stand up relatively early may also do a bit better with attention, memory and learning by the time they are preschoolers, a new study suggests.
(HealthDay)—People who've received a blood transfusion can breathe a bit easier: A new study finds no evidence that degenerative brain disorders can be transmitted via donated blood.
Matthew Gdovin, an associate professor in the UTSA Department of Biology, has developed a newly patented method to kill cancer cells. His discovery, described in a new study in The Journal of Clinical Oncology, may tremendously ...
Scientists from the National Institute of Allergy and Infectious Diseases (NIAID), the National Institute of Dental and Craniofacial Research (NIDCR), and the National Heart, Lung and Blood Institute (NHLBI), all parts of ...
Researchers at Johns Hopkins say they have gleaned two important new clues in the fight against Parkinson's disease: that blocking an enzyme called c-Abl prevents the disease in specially bred mice, and that a chemical tag ...
Inflammatory myofibroblastic tumors (IMTs)—masses of immune cells— are benign, but poorly understood. Current IMT treatments often have side effects and surgery is sometimes not an option due to the tumor's proximity ...
Many testicular cancer survivors experience hearing loss after cisplatin-based chemotherapy, according to researchers at Indiana University.
The 2009 swine H1N1 flu pandemic—responsible for more than 17,000 deaths worldwide—originated in pigs from a very small region in central Mexico, a research team headed by investigators at the Icahn School of Medicine ...