Wednesday 10 August 2016

What is angina? |


Causes and Symptoms

Usually located below the sternum, angina may radiate down the left arm and/or left jaw, or down both arms and jaws. It is ischemic in nature, meaning that the pain
is produced by a variety of conditions that result in insufficient supply of oxygen-rich blood to the heart. Some examples include arteriosclerosis (hardening of the arteries), atherosclerosis (arteries clogged with deposits of fat, cholesterol, and other substances), coronary artery spasms, low blood pressure, low blood volume, vasoconstriction (a narrowing of the arteries), anemia, and chronic lung disease.


Precipitating factors for angina include physical exertion, strong emotions, consumption of a heavy meal, temperature extremes, cigarette smoking, and sexual activity. These factors can cause angina because they may increase heart rate, cause vasoconstriction, or divert blood from the heart to other areas, such as the gastrointestinal system. Angina usually lasts from three to five minutes and commonly subsides when the precipitating factors are relieved. Typically, it should not last more than twenty minutes after rest or treatment.


Diagnosis consists of a physical examination which includes a chest X ray to determine any obvious lung or structural cardiac abnormalities; blood tests to screen risk factors such as lipids or to detect enzymes that can indicate if a heart attack has occurred; electrocardiography (ECG or EKG) to look at the electrical activity of the heart for evidence of damage or insufficient blood flow; nuclear studies such as thallium stress tests, which measure myocardial perfusion; and cardiac catheterization and coronary angiography to evaluate the anatomy of the coronary arteries, the location and nature of artery narrowing or constriction, and to assess the muscular function of the heart, including cardiac output.


Treatment depends on the specific cause of the angina. Three types of drugs are the most common form of treatment: nitrates, to increase the supply of oxygen to the heart by dilating the coronary arteries; beta-blockers, to lower oxygen demand during exercise and improve oxygen supply and demand; and calcium blockers, to decrease the work of the heart by decreasing cardiac contractility. A study published in March 2013 found that the drug Ranexa (ranolazine) might reduce symptoms of angina in patients with type 2 diabetes.




Bibliography


Dranov, Paula. Random House Personal Medical Handbook: For People with Heart Disease. New York: Random House, 1991.



McGoon, M. The Mayo Clinic Heart Book. 2d ed. New York: William Morrow, 2000.



Pantano, James. Living with Angina: A Practical Guide to Dealing with Coronary Artery Disease and Your Doctor. New York: First Books, 2000.



Parker, James M., and Philip M. Parker, eds. The 2002 Official Patient’s Sourcebook on Angina. San Diego, Calif.: Icon Health, 2002.



Zaret, Barry L., Marvin Moser, and Lawrence S. Cohen, eds. Yale University School of Medicine Heart Book. New York: William Morrow, 1992.

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