Nuclear medicine scans provide information about your body to help with your diagnosis and treatment. Substances containing a small amount of radioactivity are used to highlight different areas of the body, depending on the test being carried out.
A myocardial perfusion scan is a nuclear medicine scan that shows how well your heart muscle is being supplied with blood.
Getting ready for your scan
Please prepare for your scan as described below. This helps to make sure that the test is carried out effectively and without delay.
The day before your test
Caffeine and similar substances in some drinks and foods may affect the medicines we use during this scan. This could mean that the result of the scan is not correct.
For this reason, please do not have these foods or drinks for 24 hours before your appointment:
- Tea, coffee or green tea. Even drinks that are labelle decaffeinated can contain small amounts of caffeine – so do not drink these either.
- Chocolate or drinking chocolate.
- Coca-Cola or energy drinks that contain caffeine – some ypes of Lucozade, for example.
- Cold or pain relief medicine that contains caffeine.
You may eat or drink anything that does not contain caffeine until two hours before the time of your appointment.
Drinks that do not contain caffeine include water, dairy milk, plant-based milk, fruit juice, and caffeine-free herbal teas.
For two hours before your appointment
- do not eat any food
- drink water only
You will be able to eat after your first scan.
What to bring with you
Medicines and inhalers
We cannot carry out your scan unless we know all the medicines you are taking. This helps us choose the most appropriate method for your test.
When you come for your scan, please bring a list of all the medicines that you are taking. Please include any inhalers,
sprays and over-the-counter non-prescription medicines. If you cannot bring a list, please bring all the medicines that you are taking in their original packaging.
You can take all your medicines as normal on the day of your scan. If you will need to take any of your regular medicines when you are in the department for your scan, please bring them with you.
Clothing
Please wear loose, comfortable clothes. This allows us to attach monitoring leads and a blood pressure cuff to your body. Trousers are best as we may ask you to do some gentle exercise. Wear flat shoes or trainers. Please do not wear high heels.
Books and laptops
You are welcome to bring a book, laptop or tablet computer to look at or use while you wait during your appointment. You will be able to connect to our wi-fi network.
Food and drink
You will be able to eat and drink normally after your first scan. You will have time to go to the hospital restaurant or coffee shop, if you wish. If you would prefer to eat in the department, you can bring food with you.
People with diabetes
You do not need to change your diet or treatment. Please bring any medicines or foods that you may need.
Family and carers
You are welcome to bring a family member, friend or another adult with you when you come to the nuclear medicine department.
Children
Please do not bring children with you to your scan. Children are not allowed in the department unless they are having a scan. This is to avoid exposing them to any unnecessary radiation.
What happens during the scan?
Before your scan we carry out an assessment of your medical history so that we can select the most suitable method for your test. We will explain the procedure and answer any questions that you may have.
A small tube is placed into a vein in your arm so that we can give you medicine and a tracer used for the scan. A tracer is a substance with a small amount of radioactivity that highlights the part of the body we need to see in more detail.
Depending on your medical history, we may ask you to pedal on a seated exercise bike for four to six minutes. If you are unable to exercise for any reason, do not worry as we can still carry out the scan.
We will give you a medicine that prepares your heart for the scan. The medicine may cause mild side effects. The most common side effects are mild shortness of breath and a feeling of warmth in the body. Staff will be with you at all times.
Next, you will receive the radioactive tracer that allows us to take images of your heart. We will then ask you to rest for
between 30 and 45 minutes.
First scan
After this rest period, one of our team will call you for your first scan. We will ask you to be as still as you can, with your arms relaxed and away from your chest. The scanner is then positioned in front of your body. The scan takes approximately 15 minutes.
The scan does not cause discomfort and the machinery is quiet. Your body is not enclosed at any stage. Clinical staff will be close to you during the scan.
Second scan
A second scan is carried out after two to three hours’ rest. The second scan is a resting scan and no preparation is required. You will be able to drink (including tea or coffee) and eat between the two scans.
Two-day scans
We ask some patients, depending on their medical history and body weight, to have their two scans on separate days. This allows us to ensure that the total radiation exposure and any associated risks are kept as low as possible.
If this is the most appropriate way to carry out your scan, we will discuss this with you when you telephone to book your appointment. Each of the two visits to the department will be about 60 to 90 minutes long.
Female patients
If you are pregnant, or think you may be pregnant, please tell us before your scan. Even small amounts of radiation can harm unborn babies.
If you are breastfeeding, you can still have the scan, but it is important that you contact us for advice before you come in for your scan.
What are the risks of having the scan?
Myocardial perfusion imaging has an excellent safety record. Like most medical tests and procedures, there is some risk involved. The specialist team involved in your care will assess your medical history to make sure that the benefits of the information provided by the scan outweigh these small risks.
General risks
There is a very low risk that any medicine or exercise required for the test could cause an abnormal heart rhythm or a heart attack. The risk of heart attack is about 1 in 20,000 cases. There is also a very low risk of death, again 1 in 20,000 cases.
If you can walk at a medium pace for six minutes without problems, then the risk is even lower. We can assess your level of risk by reviewing your medical history and how you have been feeling before we start the test. You will have plenty of time to ask us questions before the test starts.
Radiation risks
The tracers we use produce a small amount of radiation. The risk of a person getting cancer because of this radiation is low (1 in 10,000 to 1 in 1,000). This level of risk is very small compared with the overall lifetime chance of getting cancer, which is approximately one in two.
Please ask us if you would like more information about this.
Advice for family members and carers
Coming to the nuclear medicine department with someone while they are having this scan results in a very small increase in radiation exposure. The additional risk of cancer to an accompanying family member or carer is very low – about 1 in 110,000.
How long does the scan take?
If you are having your scan done in one visit you can expect to be in the department for three to five hours in total. This includes periods of rest, as shown below:
- Preparation: We review your medical history, explain the procedure and answer any queries, then prepare you for your first scan
- Rest: A 45-minute rest period before the first scan
- First scan: a 15-20 minute scan
- Rest: 1.5-2.5 hours of rest between the two scans
- Second scan: a 15-20 minute scan
We always try to keep to your appointment time, but there can occasionally be delays due to technical issues or for other reasons. We will keep you informed if there is any delay.
What happens after the scan?
We then check that your scans are of good quality. Once this is done, one of our team will let you know that your visit is complete.
After your scan you can resume your normal daily activities. There are no lasting side effects and you will be able to eat and drink as normal. You will be able to drive after the scan if you wish.
When will I get the results of the scan?
We will send the results of your scan to the hospital consultant who referred you. This is normally within a week of your scan.
Contact with others living at home with you
The radioactive tracer given to you during your test continues to produce a small amount of radiation afterwards.
To reduce radiation exposure, we suggest taking the following precautions if you live with any children under 12 years old, or pregnant women:
• avoid prolonged close contact for 24 hours
• maximum duration of close contact, if needed, during these 24 hours: 30 minutes.
Close contact means being less than one metre away.
No other special contact precautions are needed. You do not need to take any special precautions if you have any pets at home.
Travelling after your scan
The small amount of radiation left in your body (even 24 hours or more after the scan) may be detectable by equipment such as airport security scanners.
If you are travelling abroad within one week of your scan, please let us know. We can provide a letter with information
about your scan that you can give to security staff if needed.
Getting to the nuclear medicine department
Royal Brompton Hospital is a 15-minute walk from South Kensington tube station, which is on the Circle, District and Piccadilly London underground lines. Several bus routes serve the hospital.
A map of the local area is provided when you arrange an appointment. For more information on reaching us, visit our website. Please note that there is no parking at the hospital and very limited parking in the local area.
When you reach the main hospital reception in the Sydney Street building, follow the signs to the lifts. Go up to Level 3 in the lift or stairs and then follow the signs to the nuclear medicine department.
If you need help, ask at the hospital reception desk. The receptionist can arrange for a porter to help you to get to the department.
Patient transport
If you are unable to get to the hospital for medical reasons, please contact your GP. They can arrange transport for you by referring you to our hospital transport department on 020 7351 8012.
Who can I contact for more information?
If you have any queries about your appointment or medical issues, please contact us on 020 7351 8666 from 9am to 5pm, Monday to Friday.
Alternatively, if you have been referred for this scan and have a medical query, you can email us at: nmadvice@rbht.nhs.uk.
You can find more information about nuclear medicine scans on our website: www.rbht.nhs.uk.
There are currently no related conditions associated with this test.
Location
Your scan will take place at either Royal Brompton or Harefield hospital. Find out more about other nuclear tests, who is likely to take care of you, and how to get to hospital.