Unstable Angina

What is unstable angina?

Angina is the chest discomfort you feel when not enough blood is getting to your heart muscle. Some people feel it as pain. Some feel it as a heaviness or a weight on the chest or arms. To others, it feels like a strangling or squeezing in the chest. The discomfort may be in the chest, arms, back, shoulder, jaw, throat, or upper belly.

There are 2 types of angina: stable angina and unstable angina.

• Stable angina is chest discomfort that is usually predictable. It happens with exercise or increased activity.
• Unstable angina is unexpected chest discomfort that can happen at any time. Little or no exercise is needed to cause symptoms. You may even have symptoms when you are resting. The pain or discomfort may last longer than stable angina, and medicine may not help. Chest discomfort may wake you up at night.

People with untreated unstable angina are at high risk of a heart attack or death. Recognizing unstable angina and treating it right away greatly lowers these risks.

How does it occur?

Unstable angina is caused by the rupture (breaking) of a plaque inside an artery of the heart. The plaque is a collection of cholesterol, fatty substances, and blood cells attached to the inner wall of the artery. The rupture causes a small blood clot to form, which partially blocks blood flow in the artery. The body tries to dissolve the clot. Chest pain or discomfort can start to go away as the clot dissolves but it will come back if you have more clotting.

How is it diagnosed?

Your healthcare provider will ask about your medical history and examine you. Some of the tests you may have are:

• an electrocardiogram (ECG or EKG) to measure the electrical activity of your heart
• a chest X-ray
• blood tests to check for heart muscle damage
• an ultrasound test called an echocardiogram to look for abnormal heart contractions
• a coronary angiogram, which uses X-rays, a special dye, and a long thin flexible tube placed inside the heart to check your blood vessels and blood flow.

How is it treated?

The goal of treatment is to help the body dissolve the clot and prevent damage to the heart. Most people with unstable angina need to be in the hospital for treatment to prevent a heart attack. Treatment may include:

• aspirin to help prevent blood clots
• bed rest
• beta blockers, drugs that decrease the heart's need for oxygen
• drugs such as heparin to treat a blood clot in the coronary artery
• nitroglycerin, a drug that slightly reduces the heart's workload.

If the chest pain does not go away with treatment with medicine, or tests show blockages in your arteries, you may need percutaneous coronary intervention or coronary bypass surgery to unblock your arteries.

Percutaneous coronary intervention (PCI) is a simpler procedure than coronary bypass surgery. Your healthcare provider inserts a balloon catheter (a flexible tube) into a blocked artery in your heart to unblock it. The balloon at the tip of the catheter is inflated. The balloon opens the artery enough to let blood flow normally. The catheter is removed, but a metal mesh device called a stent is usually left in the artery. The stent helps keep the blood vessel open. You may need to stay at the hospital a day or two after the procedure. The procedure may also be called angioplasty.

In coronary artery bypass graft surgery, blood vessels are taken from other parts of your body and attached to the blocked coronary arteries on either side of the blockage. The blood is then able to flow around, or bypass, the blockages. You will likely stay in the hospital about 1 week and then recover at home for several weeks.

How can I take care of myself?

Carefully follow your healthcare provider's recommendations. He or she will advise you when coronary angioplasty or coronary bypass surgery is needed.

Other measures to follow are:

• Don't smoke.
• Take your medicines regularly.
• Exercise according to your provider's recommendation.
• Eat a healthy diet, low in saturated and trans fat and cholesterol.
• Keep your blood pressure under good control.
• Tell your healthcare provider right away about any change in your symptoms.

Sometimes it's hard to tell a severe attack of angina from the beginning of a true heart attack. Call 911 right away if:

• You have chest discomfort (pressure, fullness, squeezing, or pain) that lasts more than 5 minutes or goes away and comes back.
• You have chest discomfort with lightheadedness.
• Your chest pain goes beyond your chest to one or both arms or to your neck or jaw.
• You have chest discomfort and are sweating a lot or having trouble breathing or are sick to your stomach.
• You still have pain after taking your nitroglycerin tablets as directed.

Any of these symptoms may be a heart attack and you need to be checked right away.