Nitroglycerin is the drug most often used. It mainly relaxes the veins and relaxes the coronary arteries a little. By relaxing the veins, it reduces the amount of blood that returns to the heart and eases the heart's workload. By relaxing the coronary arteries, it increases the heart's blood supply.

The heart's demand for oxygen also can be modified with drugs that reduce blood pressure. This reduces the heart's workload and need for oxygen. Drugs that slow the heart rate have a similar effect. Drugs called beta-blockers and calcium antagonists are used for these effects. There are many different beta-blockers and calcium antagonists, and the specific ones used are selected depending on the individual characteristics of each patient.

What procedures are used to treat angina?

Invasive techniques that improve the heart and the heart's blood supply also may be used. One of these is percutaneous transluminal coronary angioplasty. It's also known as PCI, PTCA, angioplasty, balloon dilation or balloon angioplasty. In it, a thin, flexible plastic tube (catheter) with a balloon is inserted into an artery and advanced to the blockage. Then the balloon is inflated, squeezing open the fatty plaque deposit.  Then the balloon is deflated and the catheter is withdrawn. Often a stent is also placed to hold the artery open.

Two additional techniques used to reduce coronary blockages are laser angioplasty and atherectomy. In laser angioplasty, a catheter with a laser on its tip is used to open the blockage. In atherectomy, a catheter has a rotating shaver on its tip to cut away the plaque.  These techniques also may be accompanied by stent placement.

Coronary artery bypass graft surgery is also used. In it, a blood vessel is used to route blood around the blocked part of the artery, forming a kind of detour.

Before performing any of these procedures, a doctor must find the blocked part(s) of the coronary arteries. This requires coronary arteriography,  which is done during cardiac catheterization. In this procedure a doctor guides a catheter through an artery in the arm or leg and into the coronary arteries. Then the doctor injects a liquid dye through the catheter. High-speed X-ray movies record the course of the dye as it flows through the arteries. Doctors can identify blockages by tracing the flow.  An evaluation of how the heart works also can be done during cardiac catheterization.

Other tests can be used to evaluate how well the heart works, and may be done before or after a heart attack.

How is variant angina or Prinzmetal's angina treated?

Calcium antagonists are extremely effective in preventing the coronary spasm of variant or Prinzmetal's angina. These drugs, along with nitrates, are the mainstays of treatment. Prinzmetal's angina tends to be cyclic, appearing for a time, then going away. Because of this, after six to 12 months of treatment, the calcium antagonists may be gradually reduced. In some cases PTCA or surgery are used when blockages exist along with spasm.

What are warning signs of important changes in angina?

If you have stable angina and start getting chest pain more easily, more often, at night, at rest, etc., this could signal an important change in your status. See your doctor as soon as you notice such a change (i.e., within five minutes of noticing such a change).

See the Related Items box above for links to the Cardiology Patient Page in Circulation, Journal of the American Heart Association:

• Chest Pain

• Heart and Stroke Facts
• Understanding Angina 
• Your PTCA 
• About Your Bypass Surgery 
• Your Cardiac Catheterization 
• Six Steps to a Healthier Heart 
• "What Is Angina?", "What Is Coronary Angioplasty?" and "What Is Coronary Bypass Surgery?" in Answers By Heart kit