CT Coronary Angiogram with Ivabradine
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What is a CT coronary angiogram?
This is an investigation using a high resolution CT x-ray scanner to perform a test called a CT coronary angiogram. It shows pictures of the heart and arteries and can assess if you have signs of
disease. It is a common test for chest pain but there are other indications too.
It is important that you tell your doctor if you have a history of diabetes and taking the drug metformin, or if you have a medical history of asthma or kidney problems.
Why would I need this procedure?
To identify a cause of your symptoms and/or assess your heart.
What are the alternatives?
Alternative tests include an invasive coronary angiogram performed under local anaesthetic. A tube is inserted into an artery via a small puncture, usually in the wrist. This can give a better view of the arteries but has a slightly higher risk of complications and may not be necessary at this stage.
A stress echocardiogram is a scan where ultrasound images of how the heart is pumping are compared between the heart at rest and when it is beating faster, either by using medication or exercise.
What are the potential risks and side effects?
Having a CT coronary angiogram does mean that you are exposed to some radiation. Every day we are exposed to small amounts of radiation which occurs naturally in the environment. Women who are pregnant will be advised to avoid radiation unless the test is important for the health of her and her baby. The amounts of radiation used in most medical tests are quite small with little risk, the risks involved in not having the test may well be far greater than the risks from radiation.
The scan itself is painless. Patients normally feel no ill effects from the contrast dye or medicines to slow the heart. Allergic reactions are rare. Please let your doctor know if you have poorly functioning kidneys as they may recommend an alternative test.
What are the expected benefits of treatment?
The most common aim of the test is to diagnose whether a patient’s chest pain is due to important narrowing or blockages of their heart arteries, though there are other indications. This information can lead to recommending new treatment (medication or a procedure to open up the blocked artery) but can lead to medications being stopped if the results are normal. Other
reasons for referral for this test can be to investigate valve problems or heart muscle disease.
How do I take ivabradine tablets before my scan?
You have been provided with some medication to take prior to your Cardiac CT Scan. For the scan your heart rate needs to be slowed – to the speed it is when you are asleep. This is to ensure we obtain clear images. Sometimes it is necessary to give further medication at the time of the scan if your heart is still beating fast. If you already take a beta blocker (e.g. bisoprolol) or calcium channel blocker (e.g. diltiazem) to control your heart rate you may be asked by the cardiologist to increase the dose instead of taking ivabradine.
The Cardiology Department will be in contact soon with the date of your scan so that you know when to start taking the tablets.
Please take the following dose of ivabradine:
- 10mg (2x5mg tablets)
Start taking the tablets in the morning the day before your scan. Take one dose in the morning and one dose in the evening. Then take your last dose the morning of your scan day. You only need
to take three doses. Ivabradine will not be continued after your CT coronary angiogram.
Side effects of ivabradine
Common side effects include headache, dizziness, visual disturbances (e.g. blurred vision or brightness), bradycardia (slow heart rate), atrial fibrillation (irregular heartbeat). If you experience these symptoms and are unable to continue taking ivabradine then contact the cardiology department (01908 997197), 0830-1700hrs.
Ivabradine should not be taken with the following medicines. Please inform your doctor if you are taking:
- Ketoconazole, itraconazole
- Verapamil, diltiazem
- Clarithromycin, erythromycin
- Nelfinavir, ritonavir
If you have any further questions about ivabradine please contact our patient medicines helpline which is open Monday to Friday 1400-1700 on 01908 995733.
What should I do before I come into hospital?
On the day of your procedure you should avoid caffeine (e.g., tea, coffee), alcohol, smoking, using your inhalers (apart from in an emergency if breathing gets very bad) and exercise, all of which can speed up your heart rate.
What happens during the test?
You will be asked to change into a gown. A small tube (cannula) will be inserted into a vein. For this test you lie on a bed and slide through a polo mint shaped scanner. At the start of the scan some dye (called a contrast medium) will be injected into your vein to help to show the blood vessels.
You may be given additional medicine to relax the blood vessels and another to slow your heart speed temporarily if it is still beating fast. You will be asked to hold your breath for a few seconds while the images are obtained. These are all to help get the clearest pictures of your heart possible.
How will I feel afterwards?
This depends on how you respond to the rate-lowering drugs but most people feel no ill effects.
How long will I be in hospital?
Expect to be in the CT department for between 2 to 4 hours.
Although you consent for this treatment, you may at any time after that withdraw consent. Please discuss this with your medical team.