Coronary Artery Spasm (Vasospastic Angina)

What happens during a coronary artery spasm

The coronary arteries supply the heart muscle with oxygen-rich blood. Their walls contain smooth muscle that adjusts their width. In coronary artery spasm, this muscle contracts abnormally and intensely, narrowing or completely closing the artery for minutes. The heart muscle beyond it is starved of oxygen (ischemia), causing chest pain.

Spasm can happen in arteries that look normal on angiography, or at the site of fatty plaque. It is linked to dysfunction of the artery's inner lining (endothelium) and an overactive response of the vessel muscle.

It is more common in East Asian populations, especially Japan, than in Western populations, and is usually diagnosed between ages 40 and 70.

Symptoms

• Chest pain described as squeezing, pressure, tightness or burning, behind the breastbone, sometimes spreading to the neck, jaw, shoulder or arm
• Typically at rest, especially from midnight to early morning
• Episodes usually last 5 to 15 minutes and often come in clusters
• Usually relieved quickly by nitroglycerin
• Palpitations, light-headedness or fainting if the spasm triggers an abnormal heart rhythm
• Breathlessness, nausea and sweating
• Exercise tolerance is often normal, unlike classic angina

Coronary spasm vs typical angina

Triggers and risk factors

• Smoking: the strongest modifiable risk factor
• Cocaine, amphetamines and other stimulants
• Cold exposure
• Emotional stress
• Hyperventilation
• Heavy alcohol use, sometimes the night before an early morning attack
• Certain medicines: some migraine drugs (triptans and ergots), some chemotherapy drugs such as 5-fluorouracil and capecitabine, and decongestants
• Magnesium deficiency
• Association with other spasm-related conditions such as migraine and Raynaud's phenomenon

Diagnosis

Because episodes are brief and often at night, diagnosis can be challenging.

1. ECG during an episode: temporary ST elevation that resolves when the pain stops is a classic finding.
2. Holter or event monitoring: captures ECG changes and rhythm problems during symptoms.
3. Blood tests: troponin to check for heart muscle damage.
4. Coronary angiography: looks for fixed blockages. In vasospastic angina the arteries may look normal or only mildly narrowed.
5. Provocation testing: during angiography, a medicine such as acetylcholine is injected to trigger and document spasm under controlled conditions. It is the definitive test.

Other causes of chest pain, such as coronary artery disease, reflux and anxiety, are considered.

Treatment

Avoid triggers

• Stop smoking completely. This is essential.
• Avoid cocaine and stimulants.
• Limit alcohol.
• Keep warm in cold weather.
• Review medicines that can provoke spasm.

Medicines

• Calcium channel blockers (such as diltiazem, verapamil, amlodipine or nifedipine): the first-line treatment, often taken in the evening to cover the early morning risk period. They prevent attacks in most patients.
• Long-acting nitrates: added when calcium channel blockers alone are not enough.
• Short-acting nitroglycerin (under the tongue or spray): to relieve attacks.
• Statins: may help reduce spasm and are used when atherosclerosis is present.
• Beta-blockers alone are avoided, because they can worsen spasm.
• Aspirin at high doses may worsen spasm, though low-dose aspirin is used if coronary artery disease is present.

Procedures

Stents do not treat spasm itself but may be used when a fixed narrowing is present. People who have survived cardiac arrest from spasm-related arrhythmia may receive an implantable cardioverter-defibrillator (ICD).

Complications

• Heart attack from prolonged spasm
• Ventricular arrhythmias and heart block
• Fainting
• Sudden cardiac arrest, rarely

Outlook

With treatment and avoidance of triggers, especially smoking, most people have good long-term outcomes. Many have fewer attacks over time. Those with significant coronary artery disease, multiple vessels affected or a history of dangerous arrhythmias have a higher risk and need closer follow-up.

Frequently asked questions

What does a coronary artery spasm feel like?

It usually feels like a squeezing, pressure or tightness in the chest, sometimes spreading to the jaw, neck or arm. It typically happens at rest, often at night or early morning, and lasts 5 to 15 minutes. Some people feel palpitations or faint.

What triggers coronary artery spasm?

Common triggers include smoking, cocaine and other stimulants, cold exposure, emotional stress, hyperventilation, heavy drinking and certain medicines such as triptans and some chemotherapy drugs.

Is coronary artery spasm dangerous?

It can be. Most episodes resolve without damage, but a prolonged spasm can cause a heart attack, and some spasms trigger dangerous heart rhythms. New chest pain at rest should always be assessed urgently.

How is coronary artery spasm treated?

Treatment includes stopping smoking and avoiding triggers, plus calcium channel blockers to prevent spasm, with long-acting nitrates if needed. Nitroglycerin relieves attacks. Beta-blockers alone are usually avoided because they can make spasm worse.

Can stress cause coronary artery spasm?

Yes. Emotional stress is a recognized trigger, likely through the release of adrenaline and changes in breathing. Managing stress, along with stopping smoking and taking prescribed medicines, helps reduce attacks.