Coronary angiography

Coronary angiography is an X-ray test that shows the coronary arteries, the blood vessels that feed the heart muscle. A thin, flexible tube (catheter) is passed through an artery up to the heart, and a dye (contrast) makes narrowed or blocked arteries show up on the X-ray pictures.

A doctor may suggest it to find the cause of heart-related chest pain (angina), especially if it is new, getting worse or comes at rest, or after an abnormal stress test. It is also used for valve problems, heart failure and heart attack, and to plan treatment.

The team will tell you when to stop eating and drinking.

1. You put on a gown and lie on an X-ray table. A line goes into a vein in your arm, and you may be given a mild sedative.
2. The skin over an artery, usually at the wrist or groin, is cleaned and numbed.
3. The catheter is passed into the artery and guided to the heart on X-ray. You may feel pushing, but it should not hurt.
4. Dye is injected. You may feel warm and flushed, and as if you need to pass urine, for a few seconds.
5. X-ray pictures are taken as the dye flows through the arteries.
6. The catheter is removed and firm pressure is held on the site to stop bleeding. No stitches are needed.

The test takes 30 minutes to 2 hours. If a narrowing is found, it may be treated then or later with angioplasty, which opens the artery, sometimes with a stent.

You rest in a recovery area for a few hours, lying flat if the tube went in at the groin. Most people go home the same day. Drink plenty of water to help flush the dye out. Avoid heavy lifting and hard exercise for a few days, and ask when you can drive.

Get urgent medical help if bleeding does not stop after a few minutes of firm pressure, or you have chest pain, breathlessness, fever, a red, hot, swollen site, or a pale, cold or numb arm or leg.

Angiography is generally safe, but not risk free. Bruising and soreness near the cut are common and settle in days or weeks. Infection at the cut and a mild reaction to the dye, such as an itchy rash, are less common.

Very rare but serious problems include kidney damage from the dye (usually temporary, and more likely with diabetes or kidney disease), a damaged blood vessel that bleeds, a serious allergic reaction, a heart attack and a stroke. The test uses X-rays, so you are exposed to radiation.

You may be told something before you go home, but the X-rays need careful study and the full report can take a few weeks. A normal result shows good blood flow with no blockages. An abnormal one shows which arteries are narrowed or blocked. The team will then talk through the options, which include angioplasty.

What it cannot show: it looks at the arteries. An echocardiogram shows how well the heart pumps.