Angina is characterized by the chest pain it causes, which often leads to pain that spreads down the shoulders, arm, neck, and jaw. There are four main types of angina: stable, unstable, variant, and microvascular. Although each type has a slightly different cause and severity of symptoms, they are all ultimately a result of coronary heart disease.
What is coronary heart disease?
Coronary heart disease (CHD) is the result of years of things building up in the arteries that bring oxygen rich blood to the heart. This buildup, called plaque, is a waxy substance that leads to a condition called atherosclerosis, which in turn becomes CHD. According to the National Heart, Lung, and Blood Institute, plaque consists of fat, cholesterol, and other substances that bind together in the arteries over time. Gradually, the plaque becomes harder and tightens the space through which blood moves. It becomes difficult for the oxygen rich blood to travel through these narrowed spaces, and so the heart muscles fail to receive the necessary amount of oxygen.
How does CHD cause angina?
From this point, CHD can cause angina in two different ways. The first is explained through stable angina. Stable angina is a result of the slow lack of oxygen damaging heart muscles, until eventually the chest pain begins. Stable angina generally occurs during physical or bodily stress (such as climbing stairs or periods of high anxiety) when more oxygen rich blood than normal needs to reach the heart more quickly and cannot. It is rarely a problem when the body is resting, because the amount of oxygen going to the heart is sufficient. Medications and lifestyle changes can help relieve stable angina.
The second way CHD may cause angina is explained through unstable angina. The plaque that builds up in the blood vessels can suddenly burst, causing a blood clot in the artery that brings oxygen rich blood to the heart. The heart loses the blood from that artery suddenly and severely, even while the body is resting. Unstable angina is considered an emergency, and can be a good indicator that a heart attack may happen soon. Medicine is often unhelpful, and if left alone and untreated, the condition will continue to get worse as the heart continues to be deprived of oxygen rich blood.
Variant and Microvascular Angina
Variant, or Prinzmetal’s, angina is caused by a spasm in the arteries leading to the heart. It almost always happens late at night or very early in the morning and is very rare. The artery suddenly tightens, making blood flow difficult. According to the American Heart Association, cold, cigarettes, stress, some illegal drugs, and some prescription medications designed to make blood vessels narrow can all induce variant angina. Microvascular angina is caused by coronary microvascular disease (CMD), as opposed to CHD. CMD causes the very small vessels leading to the heart to become even smaller, tightening and narrowing. Eventually, they may spasm or constrict, making oxygen-rich blood flow to the heart decreased. Episodes of microvascular angina generally lasts longer, is more severe, and occurs more frequently than other types of angina.
