Coronary artery disease is characterized by narrowing of the arteries that carry blood to the heart muscles. This results in a reduced blood flow or no blood flow to the heart. Coronary artery disease can cause angina (chest pain) and myocardial infarction (heart attack).
The blockage of these arteries is due to formation of 'plaque', on the inner lining of the artery wall. Plaque is the substance which creates the blockage, and is formed by deposits of fats, calcium and protein. As the size of the plaque deposits increases, the arteries become narrower. This condition is called 'arteriosclerosis', or hardening of the arteries.
These blocked arteries may develop new blood vessels for carrying blood to the heart muscles. During exertion or stress, these small blood vessels fail to carry the required amount of blood. Sometimes, the plaque ruptures and forms blood clots, which increase the size of the blockage, and blocks the blood flow totally. Such a situation results in 'myocardial ischemia', which denotes inadequate blood supply to the heart (myocardial) muscles.
Ischemic myocardium cannot function properly. If a large part of the myocardium is affected, it can cause damage to the tissue, which can be reversed by sufficient blood flow. Ischemia can also cause irreversible death of the tissues due to lack of blood supply. This condition is called myocardial infarction (heart attack). Hence, blockage of the coronary arteries may cause ischemia, which can lead to angina and myocardial infarction.
Symptoms of Coronary Artery Disease
A person with this disease has blockages in his coronary arteries, which can lead to angina (chest pain) and heart attack. Usually, the symptoms develop when the size of the plaque deposits increases, thereby increasing the blockage. The condition may cause chest pain and shortness of breath. The pain is often described as a tightness in the chest. The pain may also radiate to the arms, back and abdomen. Usually, such pain develops as a result of physical or mental stress. Other triggering factors include changes in temperature and heavy meals.
If the condition worsens and cause myocardial infarction or heart attack, the affected person may develop the following symptoms. A heart attack is characterized by sudden intense pain in the chest. The pain is usually located in the center of the chest, but may spread to the shoulders, arms (especially the left arm), neck, jaws, back, and the upper abdomen. Other symptoms include shortness of breath, dizziness, nausea, pale skin, sweating, vomiting, and loss of consciousness.
Symptoms are not a prerequisite for a heart attack. In some people, a heart attack may not cause any symptom. As compared to men, the symptoms may not be pronounced in women. Some women in the post-menopausal period, suffer from 'microvascular dysfunction', which means disturbance in the functioning of smaller arteries of the heart. The larger arteries remain in good working condition. This is due to many factors, like changes in female hormone (estrogen) level, smoking, and hypertension.
The wider term for this phenomenon is 'Cardiac Syndrome X', where people suffer from the symptoms of coronary artery disease due to dysfunction of smaller arteries, even if there are no blocks in larger coronary arteries. Now, it is inferred that the major cause for Cardiac Syndrome X is microvascular dysfunction. However, the general view is that, men are more prone to develop heart attacks, as compared to women.
It is always safe to prevent the disease by leading a healthy lifestyle and seeking immediate medical attention, as soon as the symptoms appear.
Disclaimer: This article is for informational purposes only, and should not be used as a replacement for expert medical advice. Visiting your physician is the safest way to diagnose and treat any health condition.