Prinzmetal Angina

variant angina, vasospastic angina, angina inversa, coronary artery spasm

Prinzmetal angina is a rare type of chest pain that strikes unexpectedly, usually during the night or early morning hours when you’re resting or asleep. Unlike typical angina that happens during physical exertion, this condition is caused by sudden spasms in the arteries supplying your heart with blood.

Table of contents

• What is Prinzmetal Angina?
• Symptoms and When They Occur
• What Causes Coronary Artery Spasms?
• Who is Affected?
• How Doctors Diagnose the Condition
• Treatment Options
• Outlook and Prevention

What is Prinzmetal Angina?

Prinzmetal angina is a rare and sometimes severe type of chest pain that differs from typical angina in important ways. The condition was named after the cardiologist who first described it in medical literature^[1]. While regular angina typically happens when you’re working hard or under emotional stress, Prinzmetal angina usually strikes when you’re relaxing or resting, often between midnight and eight in the morning^[1].

The condition is caused by sudden spasms in the coronary arteries (the blood vessels that supply blood and oxygen to your heart). When these arteries suddenly narrow or tighten, they reduce blood flow to the heart muscle, causing chest pain. The lack of oxygen reaching the heart creates the discomfort you feel, and if prolonged, this can cause damage to the heart muscle^[1].

What makes this condition particularly unusual is that many people who have it do not have significant blockages from fatty deposits in their coronary arteries, unlike people with typical angina. Instead, the problem is the abnormal spasm of the artery walls^[3].

Symptoms and When They Occur

The main symptom of Prinzmetal angina is chest pain or discomfort that occurs at rest, usually between midnight and eight in the morning. The pain typically lasts about five to fifteen minutes per episode, though it can sometimes last longer^[1]. The episodes tend to form a pattern and often come in clusters, with two or three attacks occurring close together^[5].

During an attack, you may experience chest pain that feels like squeezing, pressure, tightness, heaviness, or burning. The pain may spread to your arm, head, shoulder, back, or jaw^[1][5]. Along with chest pain, you might also feel sweaty, sick to your stomach, dizzy, or short of breath^[1][6].

One important characteristic of Prinzmetal angina is that people with this condition usually can tolerate exercise well without triggering chest pain, which is very different from typical angina^[3]. However, in some cases, exercise, stress, or exposure to cold may trigger an episode^[1].

In rare instances, if the spasm does not stop, it can lead to dangerous heart rhythm problems or even a heart attack. These serious complications require immediate medical attention^[4][5].

What Causes Coronary Artery Spasms?

The underlying cause of why the coronary arteries go into spasm in people with Prinzmetal angina is not completely understood. However, researchers believe it involves increased reactivity of the blood vessels to certain triggers that cause them to constrict abnormally. This may be related to problems with the cells lining the blood vessels (endothelial dysfunction) or with the smooth muscle cells in the coronary artery walls that control whether the vessels widen or narrow^[3].

Several specific factors can trigger coronary artery spasms in people with this condition^[1][6]:

• Certain medications that narrow blood vessels, such as treatments for migraine headaches (like sumatriptan) or decongestants containing ephedrine or pseudoephedrine
• Use of recreational drugs, particularly cocaine and marijuana
• Smoking tobacco
• Emotional stress
• Exposure to cold temperatures
• Physical exercise (in some cases)

The balance between the sympathetic and parasympathetic nervous systems, which help regulate blood flow in the coronary arteries, may also play a role. An imbalance in this system can lead to excessive constriction of the blood vessels^[3].

Who is Affected?

Prinzmetal angina is rare, accounting for about two out of every one hundred angina cases^[1]. The exact number of people affected is not well known, partly because the condition may be misdiagnosed or confused with other conditions^[3].

The condition affects both men and women. However, studies show differences in who is most likely to develop it. In general, people with Prinzmetal angina tend to be younger than those with typical angina caused by blocked arteries^[1]. The average age when symptoms first appear is around the fifth decade of life (ages forty to fifty)^[3].

Heavy cigarette smoking is a common risk factor among people with Prinzmetal angina^[4]. The condition is also found more often in people who have other conditions related to blood vessel spasms, such as migraine headaches and Raynaud’s phenomenon (a condition where fingers and toes get cold and change color)^[1].

Research has shown that people of Japanese descent have a higher risk of developing Prinzmetal angina compared to Caucasian populations, with about three times higher occurrence. Within the Japanese population, females are more likely to experience the condition^[3].

While Prinzmetal angina can affect people with high cholesterol or high blood pressure, it also occurs in people who do not have these conditions. Studies on whether the condition is hereditary have not shown strong evidence that it runs in families, though some research suggests there may be a genetic factor^[1].

How Doctors Diagnose the Condition

Diagnosing Prinzmetal angina can be challenging because many people with this condition do not have obvious blockages in their coronary arteries that would show up on standard tests. Doctors should suspect Prinzmetal angina when chest pain occurs at rest or during sleep, happens in clusters, or when a person shows no evidence of other forms of heart disease^[4].

The key to diagnosis is detecting changes in the heart’s electrical activity during an episode of chest pain. An electrocardiogram (ECG) recorded during an attack typically shows ST-segment elevation, which indicates reduced blood flow to a part of the heart muscle^[3][7]. Once the chest pain resolves and the spasm ends, these ECG changes disappear, which is an important clue that helps distinguish Prinzmetal angina from a heart attack^[7].

Your healthcare provider may order several tests to diagnose Prinzmetal angina^[1][6]:

• Stress tests to check how your heart responds to physical activity
• Coronary angiography (an X-ray imaging test that shows the coronary arteries) to rule out significant blockages
• Ambulatory electrocardiogram (a portable device that records your heart’s electrical activity over twenty-four hours or longer)
• Blood tests to check for damage to the heart muscle

Because there may be no obvious signs of heart problems when you’re not having an attack, doctors sometimes need to try to trigger an episode using certain substances such as acetylcholine or ergonovine during a coronary angiography. This allows them to see the spasm happen and confirm the diagnosis^[1][7].

Treatment Options

The main goals of treating Prinzmetal angina are to relieve symptoms during attacks, prevent future episodes, and reduce the risk of serious complications like heart rhythm problems or heart attacks.

When you’re having an attack, the most important immediate treatment is nitroglycerin, which quickly relaxes the coronary arteries and relieves the spasm. If you’ve been diagnosed with Prinzmetal angina, you should always carry your nitroglycerin medicine with you^[1]. If the first dose does not help after five minutes, you should take another dose. If symptoms continue five minutes after the second dose, you should call emergency services immediately^[1].

For long-term management, doctors typically prescribe medications to prevent spasms and reduce the frequency of attacks^[1][6][13]:

• Calcium channel blockers are the first-line treatment. These medications help relax the smooth muscle in the coronary artery walls, preventing them from going into spasm
• Long-acting nitrates can be added if calcium channel blockers alone do not adequately control symptoms
• In some countries, a medication called nicorandil is available and can be used as an additional treatment

It is important to note that beta-blockers, which are commonly used for typical angina, should be avoided in people with Prinzmetal angina. These medications can actually make the spasms worse by allowing certain receptors in the blood vessels to be more easily stimulated, causing increased constriction^[9].

In addition to medications, your healthcare provider will counsel you about making heart-healthy lifestyle changes. This includes quitting smoking if you smoke, avoiding substances that can trigger spasms (like certain decongestants and recreational drugs), managing stress, and maintaining a healthy weight^[1][6].

In rare cases where Prinzmetal angina causes dangerous heart rhythm problems, doctors may recommend implanting a device such as a pacemaker or implantable cardioverter defibrillator (ICD) to protect against life-threatening rhythms^[15].

Outlook and Prevention

With proper treatment, most people with Prinzmetal angina can manage their symptoms effectively and reduce the frequency of attacks. The outlook is generally good when the condition is recognized and treated appropriately with medications that prevent spasms.

However, it is important to understand that Prinzmetal angina increases your risk of having a heart attack or developing dangerous heart rhythm problems. This risk is higher if you also have significant blockages in your coronary arteries or if you have unstable angina^[4]. Regular follow-up with your healthcare provider is essential.

You can take several steps to help prevent angina attacks and reduce your risk^[1]:

• Avoid known triggers as much as possible, including stress, cold temperatures, and substances that cause blood vessel constriction
• Always carry your angina medicine with you and use it as your doctor has instructed
• If you smoke, work with your healthcare provider to quit smoking
• Maintain a healthy weight through balanced eating
• Stay as physically active as your symptoms allow
• Limit alcohol consumption if you drink
• Take all prescribed medications regularly, even when you’re feeling well

You should attend regular follow-up appointments with your healthcare provider. Initially, you may need visits every four to six months for the first year after diagnosis, and then every six to twelve months as long as your condition remains stable. Your treatment plan may need to change if your angina worsens or becomes unstable^[22].

It is crucial to know when to seek emergency medical help. If you develop chest pain that does not go away after resting and taking your medicine as prescribed, or if you experience sudden severe chest pain, sweating, nausea, or light-headedness, you should call emergency services immediately. These could be signs of a heart attack or other serious complication requiring immediate treatment^[1].