Stable-Unstable Angina

Frequently Asked Questions

What is it?

Angina pectoris, or angina, is a symptom of chest pain or pressure that occurs when the heart is not receiving enough blood and oxygen to meet its needs. Stable angina usually occurs in a predictable fashion during or after physical exercise or emotional stress.

Also Known As: Angina Pectoris, Stable or Unstable

What are the basic facts?

• Angina pectoris, or angina, is a symptom of chest pain or pressure that occurs when the heart is not receiving enough blood and oxygen to meet its needs.
• Angina results from coronary artery disease (CAD), which is an accumulation of plaque inside the coronary blood vessels.
• There are two types of angina – stable and unstable.
• Stable angina usually occurs in a predictable fashion during or after physical exercise or emotional stress.
• Unstable angina occurs in unexpected or unpredictable times, such as at rest.
• Unstable angina symptoms are a medical emergency, and may be a precursor for a heart attack. Thus, medical attention should be sought immediately.

A more detailed explanation

Angina pectoris, or angina, is a symptom of chest pain or pressure that occurs when the heart is not receiving enough blood and oxygen to meet its needs. In general, angina results from plaque made of cholesterol or other fats building up in the coronary arteries. The accumulation of this plaque is known as coronary artery disease (CAD). When enough plaque accumulates inside a person’s coronary arteries, blood flow past the plaque is reduced, depriving the heart muscle of its needed nutrients and oxygen. As a result, angina symptoms can occur. Angina is more likely to occur when the heart is working harder and requiring additional blood flow, such as during physical activity or emotional stress.

Angina is classified into two types – stable angina and unstable angina. Stable angina results from the gradual accumulation of plaque in the coronary artery. As this accumulation increases, angina symptoms begin to occur in a predictable fashion during or after physical exercise or emotional stress. This predictable pattern can persist for weeks, months, or even years. The kinds of activities that can cause stable angina include walking up a hill or a flight of stairs, doing housework, experiencing severe emotional stress or anxiety, having sex, exposure to cold temperatures, or consumption of heavy meals. Although the symptoms are bothersome, they do not usually indicate that a heart attack is imminent.

Unstable angina results from the sudden rupture of a plaque, which causes a rapid accumulation of platelets at the site of rupture and rapid obstruction of blood flow in the coronary artery. As a result, unstable angina symptoms occur suddenly, often in an unexpected or unpredictable fashion. The symptoms may be new, prolonged, more severe, or occur with little or no exertion. Unstable angina may also be less responsive to nitroglycerin medication than stable angina. Unstable angina is a medical emergency . Unchecked, the accumulation of platelets and obstruction to blood flow can result in a heart attack. This risk of heart attack remains even if the unstable angina symptoms lessens or disappears. Thus, if unstable angina occurs, seeking immediate medical attention is very important.

Stable angina symptoms

Stable angina pain usually lasts between 2 and 15 minutes. The pain associated with angina can vary from person to person, and people make different comparisons to express the pain they feel. Many people describe angina as:

• Pain or pressure
• Tightness
• A heavy, crushing feeling in the chest, neck, throat, jaw, shoulder and/or arm
• Discomfort just below the breastbone
• Burning similar to heartburn or indigestion
• Shortness of breath

Some people report that stable angina feels mild when it begins and then increases in intensity. Stable angina sometimes brings about other symptoms such as anxiety, nausea, lightheadedness, or profuse sweating.

Typically, ceasing physical activity and resting for a short time allows stable angina symptoms to subside. The pain from stable angina may also subside if a person takes nitroglycerin medication. If the symptoms last more than 15 minutes or are not relieved with nitroglycerin, medical attention should be sought since the pain may indicate unstable angina or a heart attack, rather than stable angina.

Causes and risk factors

Stable angina results from coronary artery disease (CAD). Thus, risk factors for the development of CAD are also risk factors for stable angina:

• Smoking
• Having high cholesterol levels
• Not exercising regularly
• Having hypertension, or high blood pressure
• Eating a diet high in saturated fat and cholesterol
• Having diabetes mellitus
• Being more than 30 percent over one’s ideal weight
• Having family members (especially parents or siblings) who have had coronary artery disease (CAD) or a stroke
• Using stimulant or recreational drugs, such as cocaine or amphetamines (this is not a risk factor for developing CAD, but may increase the impact of any CAD which is present)