Contrast echocardiogram (echo)

What is a contrast echocardiogram?

You may have already had an echocardiogram (usually just called an ‘echo’) performed. This is a non-invasive imaging test using ultrasound to look at your heart.

Ultrasound is very high-frequency sound which cannot be heard by the human ear. It is used to gain information about the heart muscles, chambers of the heart and structures within the heart such as the valves. The test is safe and painless.

A contrast echocardiogram uses imaging ultrasound combined with an injection of specialist ultrasound enhancing agent to improve the quality of the images that are recorded.

Why am I being asked to have this test?

In some cases, the test is done when accurate information about the pumping function of your heart is required and your previous echo image quality has not been sufficient to give this information.

In other cases, the test is carried out after a heart attack or stroke when an echo has suggested the presence of a thrombus (blood clot) in the heart.

We use an ultrasound enhancing agent (called SonoVue®) to do this.

What does the echo involve?

• You will be taken into a room with usually a cardiologist and/or a specially trained cardiac physiologist.
• The test will be explained to you in detail, including a discussion about the possible risks. You will then be asked to sign a consent form. By signing this form, you will have agreed to have the test performed and that you understand why it is needed. This does not take away your right to have the test stopped at any time.
• You will be asked to undress to the waist but you will be offered a hospital gown to wear. The gown should be left open to the front (like a coat). You will then be asked to lie on a couch and ECG stickers will be attached to your chest and connected to the echocardiogram machine. This allows us to monitor your heart rate and rhythm during the test.
• A small plastic tube (cannula) will be inserted into one of the veins in your arm. This will be used for the injection of the ultrasound enhancing agent. You will then be asked to lie on your left-hand side. If you are unable to lie on your left side, we can carry out the echo while you are lying on your back. The test is performed in semi-darkness so the lights will be dimmed once you are comfortable.
• The physiologist will place the echocardiogram probe on your chest (this is like a thick blunt pen) with cold lubricating jelly (this helps to get good contact with the skin).
• While the physiologist is taking a few baseline pictures of your heart, the doctor will be mixing up the ultrasound enhancing agent. Once this is done the doctor will inject the contrast through the cannula into the vein and the physiologist will take a number of pictures of the heart from different areas on the chest. More contrast may be injected during the scan to keep good image quality.
• The doctor and physiologist may discuss the images during the test to make sure that they are happy and that they have enough information before deciding that the test is at an end.
• The test will take about 30 to 45 minutes to complete.

Do I need to take any special precautions before the test?

You should take all of your usual medication as normal on the day of the test. You can also eat and drink normally. We advise that you keep hydrated (having plenty to drink) and warm before the test. This increases the chance that we can access a vein for the cannula insertion during the test.

Risks, contra-indications and possible side effects of the test

SonoVue® is contraindicated (cannot be used):

• If you are allergic to sulphur hexafluoride, macrogol 4000, distearoylphosphatidylcholine, dipalmitoyl-phosphatidylglycerol sodium or palmitic acid.
• If you have been told you have a right-to-left heart shunt.
• If you have severe pulmonary hypertension (pulmonary artery pressure more than 90mmHg).
• If you have uncontrolled hypertension (high blood pressure).
• If you have adult respiratory distress syndrome (a severe, medical condition characterised by widespread inflammation in the lungs).
• Please let us know if you are pregnant, as the test should not be carried out until after the birth of your baby. If you are breastfeeding, you can resume after 2 or 3 hours as the ultrasound enhancing agent is quickly removed from the body by breathing.

SonoVue® is considered a medicine, and therefore it may cause side effects, although not everybody will get them. Most of the side effects to SonoVue® are rare and usually not serious. Some patients may experience serious side effects which may require treatment.

Please let the Cardiac Investigations team know if you have a heart condition which has recently worsened, including increasing frequency of angina (chest pains) or rhythm disturbance or if you have artificial heart valves.

We also need to know if you have an acute general inflammation or infection and if you have any severe liver or kidney disease.

During the test, tell the doctor straight away if you notice any of the following side effects, as you may need medical treatment:

• Swelling of the face, lips, mouth or throat which may make it difficult to swallow or breathe; skin rash; hives; swelling of the hands, feet or ankles.

Common side effects of SonoVue® include:

• Headache, feeling sick (nausea) or abdominal pain, flushing or feeling hot or sensations of dizziness during the injection. Occasionally there may be some redness or itching at the cannula site.
• If you are taking any blood thinning medication, you may bruise or bleed more easily when the cannula is inserted or removed.

Less common/rare side effects of SonoVue® include:

• Blurred vision; a decrease in blood pressure which may lead to feeling faint, itching (pruritis), back or chest pain, generalised pain or fatigue.
• A severe, life-threatening, allergic reaction to SonoVue® during the test (1 in every 10,000 patients).

Most symptoms usually go away when we stop the test.

There will always be medical professionals present during the test, who are trained to manage any of the complications mentioned.

After the procedure

You may be told the results immediately, but some findings take longer to interpret and may need a second opinion. You can carry on with your normal activities after the procedure. You can drive as normal and operate machinery following the test.

Contact information

If you have any questions about your planned contrast echocardiogram, please contact your consultant’s secretary or Cardiac Investigations.

Cardiac Investigations

Tel: 0300 422 6551

Monday to Friday, 9:00 am to 4:00 pm