Everything You Need to Know About Angina

Medically reviewed by Jeffrey S. Lander, MD

Angina pectoris, or angina for short, is chest discomfort that occurs when the heart doesn't get enough oxygen. It can feel like pressure, squeezing, or pain in the chest. Angina can be stable, occurring chronically in people with coronary blockages, particularly during exercise or exertion. New or worsening angina is considered unstable angina and can progress to a heart attack.

This article will discuss angina and its types, causes, diagnosis, and management.

What Is Angina?

Angina is a symptom that occurs when there is a problem with the flow of blood to the heart. The heart is a constantly working muscle that requires a great deal of oxygen and energy to function. Blood is supplied to the heart by the coronary arteries.

Any impairment of the supply of blood from the coronary arteries, such as in coronary atherosclerosis, can lead to chest discomfort, which is classically described as a dull pressure in the center of the chest that may radiate to the arm or jaw.

Types of Angina

Angina is classified as either stable or unstable. Stable angina is chronic chest pain that occurs with exertion and reliably improves with rest. It's usually experienced when the heart works harder and requires more blood and oxygen, such as during exercise or emotional stress. Other triggers include eating a heavy meal or extremes of temperature.

With exertion, the heart rate increases, and the heart pumps more forcefully to supply blood to the body, thus requiring a greater demand for oxygen. However, a blockage in the coronary arteries limits the amount of blood supply to the heart.

Unstable angina, on the other hand, is new angina, which occurs at rest or has become more frequent, longer-lasting, or severe. Unstable angina is considered a type of acute coronary syndrome. It's a medical emergency since it can progress to a heart attack and requires hospitalization for evaluation and treatment.

Angina can also be classified according to its causes. It usually is caused by atherosclerosis, a hardening and blockage of the artieries caused by a buildup of cholesterol plaques. Other types of angina are:

• Microvascular angina, due to blockages of the small blood vessels of the heart that can't be visualized. It also may be caused by spasms in the microvasculature.

• Variant angina, also known as Prinzmetal angina, is due to vasospasm, or a sudden temporary constriction, of a coronary artery. It typically occurs when a person is at rest. This classically occurs in the early morning hours and can be triggered by stress, cold, smoking, and certain medications such as nonsteroidal anti-inflammatory drugs (NSAIDs), and cocaine.

Angina Symptoms

Most people associate chest pain with blockages in the heart. However, people with angina may not ever have pain. They may instead describe a tightness, pressure, or squeezing sensation that isn't necessarily painful.

Angina is often described as a dull feeling in the area under the breastbone (sternum), though it's difficult to locate the precise position. The discomfort can radiate up to the neck, arms, upper abdomen, back, or jaw. Shortness of breath is another common symptom. Other symptoms can include the following:

• Nausea

• Light-headedness

• Numbness

• Palpitations

• Epigastric discomfort (discomfort at the upper abdomen just below the ribs)

• Sweating

Angina typically lasts for a few minutes, gradually increasing in severity before dissipating with rest.

Angina in Females

While chest pain is the most common symptom of angina regardless of sex, people assigned female at birth are more likely to have nonclassic symptoms. This can make the diagnosis more challenging and is one potential contributor to disparities in heart disease diagnosis and management in women.

Angina Treatments

Once a diagnosis of chronic, stable angina is made, the treatment plan includes lifestyle changes and medications to alleviate symptoms and prevent complications such as heart attack and death. Cardiac rehab is a supervised program for people diagnosed with heart disease that provides education, exercise prescription, and tailored advice on managing your condition.

Lifestyle Changes

The following lifestyle changes are recommended for heart health and to prevent future cardiovascular events in those with or without heart disease:

• Getting regular physical exercise: The American Heart Association recommends at least 150 minutes of moderate-intensity exercise per week. Cardiac rehab can help determine an appropriate exercise prescription and instructions.

• Eating a heart-healthy diet: This diet is rich in vegetables, fruits, whole grains, legumes, and fish and is low in processed foods, sodium, and trans fats

• Quitting smoking

Medications for Angina

Medications to treat angina include:

• Aspirin, an antiplatelet medication that helps thin the blood

• Statins to lower cholesterol

• Beta-blockers to slow heart rate and decrease workload on the heart

• Calcium channel blockers decrease stress on the heart by lowering heart rate and blood pressure

• Angiotensin converting enzyme (ACE) inhibitors to decrease blood pressure

• Nitrates to relax blood vessels

• Ranolazine to relaxes the heart muscle

Procedures

In some cases, such as if symptoms are affecting daily life significantly despite optimal medication regimen, your cardiologist may recommend revascularization to restore blood flow to the heart. This can be achieved through stenting or surgery.

Stenting is performed during a procedure called coronary angioplasty to open blocked coronary arteries. During this procedure, a cardiologist uses balloon-tipped catheters under X-ray guidance to reach the coronary arteries, open up the blockage, and place a stent, a flexible tube.

In certain cases, surgery is preferred. This is done with coronary artery bypass grafting (CABG).  A cardiothoracic surgery will harvest a blood vessel (typically a vein from the leg) and use it to bypass the blockage in the heart.

What Causes Angina?

Angina is caused by anything that impedes blood flow to the heart muscle. Most commonly this is from atherosclerosis, or cholesterol plaques. However, other causes of angina include:

• Congenital coronary malformations (coronary arteries with abnormalities since birth)

• Coronary vasospasm, a narrowing of the arteries due to blood contracting persistently (Prinzmetal's angina)

• Problems with the small blood vessels bringing oxygenated blood to the heart (microvascular angina)

Risk Factors for Angina

Angina is most often caused by atherosclerotic coronary artery disease, which is the most common form of cardiovascular disease. Risk factors include certain medical conditions and lifestyle factors:

• High cholesterol

• High blood pressure

• Diabetes

• Having obesity

• Chronic kidney disease

• Certain female-specific risk factors such as preeclampsia, early menopause, polycystic ovary syndrome (PCOS)

• Family history of heart attack, especially at a young age

• Smoking

• Sedentary lifestyle

How Is Angina Diagnosed?

There are many potential causes of chest pain, some of which are benign while others may be life threatening. So it’s important to receive a proper diagnosis. Your healthcare provider may have suspicion for angina based on your description of chest pain and order diagnostic tests. Tests to diagnose angina include:

• Electrocardiogram (ECG or EKG)

• Stress test, such as exercise stress test, stress echocardiogram, myocardial perfusion imaging (nuclear stress test)

• Imaging tests such as echocardiogram, coronary computed tomography angiography (CTA)

• Coronary angiography, an invasive test in which cardiologists use catheters, X-rays and contrast dye to visualize the coronary arteries

Angina Complications and Outlook

In most cases, angina is due to blockages in the coronary arteries due to atherosclerosis, a buildup of cholesterol plaques. Plaque in the coronary arteries can become unstable and lead to blood clots in the coronary artery that abruptly stop blood flow to the heart, leading to a heart attack. This can be life-threatening.

Additionally, atherosclerosis in the coronary arteries means that arteries in other parts of the body are likely affected. This includes the following:

• Carotid artery disease caused by atherosclerosis in the arteries in the neck, which can lead to stroke

• Peripheral artery disease, caused by atherosclerosis in the leg arteries, which can impair blood flow to the legs leading to pain, and poorly healing wounds that sometimes require amputation

• Intracranial atherosclerosis in the arteries in the brain that can lead to stroke

Fortunately, there are ways to decrease your risk of heart attack, stroke, and peripheral artery disease with the lifestyle changes and medical therapies discussed above.

Summary

Angina is a serious condition related to impaired blood flow to the heart causing chest discomfort. The primary cause is atherosclerosis or cholesterol plaques in the coronary arteries. It increases risk of heart attack, and is associated with blockages in other arteries that can increase risk of stroke.

Treatment goals include managing symptoms and reducing risk of cardiovascular events. Lifestyle changes and medications are the cornerstone of managing angina, and the condition should be closely followed by a cardiologist.