Coronary Artery Disease

11 Pages 2845 Words

Coronary Artery Disease, or CAD, is the single leading cause of death in the United States, accounting for over 900,000 deaths annually. More estimates show that over 3 million Americans suffer from occasional chest pains due to coronary artery blockages. However, the U.S. is still only 17th in cardiovascular disease mortality worldwide. Other countries, such as Russia, Poland, Hungary and Finland, continue to have higher mortality and morbidity from CAD than the U.S., making this a world-wide healthcare issue. As common as CAD has become, it still has not been eradicated by preventative measures. In fact, it is only within the last 40 or 50 years that the role of cholesterol and dietary fat in the development of this disease has really been understood. However, a number of other “risk factors” have also been identified, including family history, hypertension, smoking, diabetes, and lifestyle issues such as lack of exercise or Type A personality.
The heart is a muscle just like the muscles in the arm or leg. Any of these muscles, including the heart, is composed of millions of small cells which contract, or shorten, under the proper conditions. A muscle cell, also known as myocyte, can physically shorten due to the unique manner foreshortening the length of the cell in the process. When millions of such cells act simultaneously, the muscle body shortens and develops a force of contraction. This is the same mechanism that occurs when you raise your arm, walk and lift.
In the heart, the muscle fibers are aligned in a circular manner to form a conical shaped chamber. As the heart muscle cells contract in unison, blood is forced out of the chamber into the vascular tree, then from there it flows to every organ and cell in the body. In essence, the vascular tree is the highway to the rest of the body. The task of continuously pumping the blood to the body requires a great deal of energy. The heart must have its own ...