Angina is recurrent chest pain that originates under the breastbone , often spreading to the neck, jaw, arms, and upper back. The nature of the pain varies, but it is usually described as a sensation of pressure, tightness, heaviness, or choking,and it is often accompanied by shortness of breath. Severe angina may feel like a heart attack, but it is a temporary condition that does not cause permanent damage. It does, however, signal an increased risk of a heart attack. Angina occurs when the heart muscle is not getting enough oxygen. The most common cause is arteriosclerosis, a narrowing of the coronary arteries due to deposits of fatty plaque. The narrowed arteries may be able to deliver enough oxygen rich blood to the heart muscle to carryon normal activities. But when the heart must work harder, such as during unaccustomed physical exertion or periods of stress, the heart muscle becomes starved for oxygen, a condition called ischemia. A heavy meal or exposure to cold may also precipitate angina because blood flow is diverted from the coronary arteries to other parts of the body. Some people experience angina while resting or even sleeping. This unprovoked, or variant, angina is sometimes caused by a spasm in the coronary artery, usually at the site of fatty deposits. More often, it is classified as unstable angina, and is a warning sign of impending heart attack.
Diagnostic Tests and Procedures
There is no specific test for angina, but a doctor can usually tell whether or not the pain arises from the heart by asking three key questions: What provokes the discomfort? What is it like? And what alleviates it? Angina is suspected when there are other cardiovascular risk factors, such as cigarette use, a family history of early heart attacks, elevated blood pressure and cholesterol levels diabetes, and so forth. During a physical examination, the doctor listens carefully to the heart for any abnormal sounds or beats. Routine tests include an electro car diogram (ECG), blood pressure measurement, blood and urine tests, and a chest X-ray. If a doctor suspects angina, additional tests may be ordered to assess any underlying heart disease. An exercise stress test can usually confirm that physical exertion brings on ischemia. This test is sometimes combined with echo cardiography, an examination using high frequency sound waves, or nuclear scanning, in which thallium or another radioactive substance is injected into the blood stream and then tracked by special gamma cameras. These last two tests can often pinpoint the areas of heart muscle that are deprived of blood. A more invasive procedure, cardiac categorization, is needed to make a precise diagnosis of coronary artery disease. In this examination, a thin, flexible tube is inserted into an artery in the leg (or less commonly, the arm) and threaded to the heart A dye is then injected into the coronary arteries to make them visible on X-rays.
There are numerous effective treatments for angina, ranging from exercise conditioning and medication to surgery. Depending upon the severity of symptoms and the degree of coronary disease, lifestyle changes and drugs are usually tried first, with surgery reserved for cases that cannot be controlled by more moderate approaches.
After an exercise stress test, a doctor prescribes a regimen of physical activity designed to increase endurance without provoking angina. Patients are taught to monitor their heart rate, and to increase their exercise gradually. This conditioning prompts the coronary arteries to build collateral circulation, increasing blood flow to segments of the heart muscle receiving inadequate blood.