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Coronary Vasospasm

Coronary vasospasm (CAS) is when your heart's arteries suddenly constrict, causing spasms that trigger symptoms much like a heart attack. This includes pain and pressure in the chest.

CAS can sometimes cause dangerous heart rhythms, heart attacks, and even sudden death. That's because the narrowing of one or more blood vessels prevents the heart muscle from getting all the oxygen it needs.

Treatments include medicines that dilate and relax your arteries and lifestyle changes.

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What Is Coronary Vasospasm?

Coronary vasospasm (CAS) is a sudden and reversible narrowing of the blood vessels that supply oxygen to your heart muscle. These spasms can cause symptoms that are much like what a heart attack feels like.

Other names for CAS include:

  • Coronary artery vasospasm, or CAVS
  • Prinzmetal's angina.
  • Variant angina.

Most people with CAS are between the ages of 40 and 70. The prevalence of CAS decreases after age 70.

CAS is rare and accounts for only two out of every 100 cases of angina.

Types of CAS

Kounis syndrome is a little-known form of CAS caused by an allergic reaction to mediators of inflammation, such as histamines and leukotrienes.

Kounis syndrome is also known as allergic angina or allergic myocardial infarction.

Coronary vasospasm causes

CAS happens when your heart's blood vessels narrow. This lessens the supply of oxygen to your heart muscle, causing painful spasms.

Triggers for these spasms include:

  • Chronic stress.
  • Exposure to cold.
  • Medicines that constrict or narrow your blood vessels.
  • Smoking.
  • Alcohol withdrawal.
  • Stimulant drugs, including amphetamines and cocaine.
  • Magnesium deficiency.
  • Rapid breathing or gasping.
  • Beta-blockers or other drugs that decrease the breakdown of acetylcholine — a chemical in the brain.

In some cases, CAS can form without a known cause or trigger.

Coronary vasospasm risk factors and complications

CAS occurs most commonly in people:
  • Who smoke.
  • With heart disease risk factors, including diabetes, high blood pressure, or high cholesterol.
  • With a high level of C-reactive protein, or Hs-CRP, a marker of inflammation in your body.
  • Between the ages of 40 and 70.

CAS is more common in men than women.

Left undiagnosed or untreated, it can lead to serious complications, including:

  • Life-threatening irregular heart rhythms.
  • Heart attack.
  • Sudden death.

When there's no heart blockage, CAS is the main cause of ischemic, or coronary heart disease. That's when the heart isn't getting enough oxygen or blood.

About 50% of people with angina (chest pain and pressure), and 57% of people with acute coronary syndrome have CAS.

How to prevent CAS

Medical care and lifestyle changes are the mainstays of treating and preventing CAS.

To help prevent CAS:

  • Quit smoking.
  • Reduce other heart disease risk factors. This includes controlling diabetes, high blood pressure, and high
  • cholesterol.
  • Quit the use of stimulant drugs, such as amphetamines and cocaine.

Why choose Magee-Womens Heart Program for coronary vasospasm care?

Doctors can refer both women and men to Magee-Womens Heart Program.

Women's hearts differ from those of men. Heart disease can cause different symptoms in both women and men.

At Magee-Womens Heart Program, we know those differences and take them seriously. We're here to help all our patients — women and men — overcome heart problems.

Coronary Vasospasm (CAS) Symptoms and Diagnosis

Warning signs and symptoms of CAS are like those of a heart attack.

You may feel in your chest:

  • Pain
  • Pressure
  • Tightness
  • Squeezing

These sensations often occur on the left side of your chest or under your sternum or chest bone. The pain may also move to your neck, jaw, and left arm.

CAS mostly occurs when you're resting. The spasms can be painful enough to wake you up. They can also occur during normal daily activity.

CAS episodes usually last 15 minutes. In some cases, spasms are silent and you won't feel any symptoms.

Often a chronic condition, CAS episodes can happen many times a day, yearly (or less), or something in between.

If you have CAS, call 911 or go to the emergency room if:

  • You feel like you're going to pass out.
  • Your chest pain doesn't get better after taking your prescribed dose of nitroglycerin.
  • You're having other symptoms of a heart attack. These include pain in your upper body, shortness of breath, nausea, lightheadedness, or breaking out in a cold sweat.

Diagnosing coronary vasospasm

CAS can be hard to diagnose. If your doctor suspects you have CAS they should do a complete cardiovascular exam.

They may also want to do one or some of the following tests:

  • Blood tests to check for related cardiac biomarkers.
  • Coronary angiography.
  • ECG.
  • Echocardiography.
  • Holter monitor. You may need to wear this for 48 to 72 hours to record your heart's electrical impulses while you sleep.

Coronary Vasospasm (CAS) Treatment

UPMC Magee-Womens Heart Program can help you manage your heart health.
We can help you reduce your risk for CAS. We can also help prevent it from happening again.

When treating CAS, the goals are to:

  • Reduce chest pain.
  • Prevent severe complications, such as a heart attack.
  • Prevent or reduce future spasms.

Medicine to treat CAS

Along with suggesting lifestyle changes, doctors mainly treat CAS with medicine.

Your doctor may instruct you to place one or more nitroglycerin tablets under your tongue during a CAS attack. This helps relax your heart arteries to reduce chest pain and control spasms.

If your symptoms don't improve after taking it, seek medical help right away. Only a health care professional can tell whether you're having a heart attack.

Common drugs to help prevent CAS attacks include:

  • Calcium channel blockers. Side effects can include low blood pressure or swelling in your legs.
  • Long-acting nitrates. Side effects can include headache, flushed skin, or light-headedness.

After six to 12 months of treatment, your doctor may reduce your medication. Or you may need to stay on it long-term.

Prognosis for coronary vasospasm

CAS is often a chronic condition. Between 4% to 19% of people have repeat episodes.

The prognosis for CAS depends on your age.

Some people may get acute coronary syndrome, an umbrella term for the sudden blockage of blood flow to the heart muscle. These people have a higher risk of poor prognosis if they're older or have an impaired left heart ventricle.

The risk for an event such as a heart attack is highest three months after a CAS attack.

For most, the outlook for CAS is good as long as you take your medicine and reduce risk factors, such as smoking.