Cardiac Investigations

Patients attending an outpatient appointment may commonly require one or more of the following tests on the day of clinic:

• ECG (electrocardiogram), which records the rhythm and electrical activity of your heart
• Echocardiogram (ultrasound scan), which uses sound waves to produce a detailed picture of your heart
• Blood testing a sample of your blood is taken for testing in a laboratory

Other tests that can be arranged to find out how the heart is doing include:

• 6 minute walk test measures the distance you can walk quickly in 6 minutes (if you come to the Pulmonary Hypertension clinic)
• 24 hour Blood Pressure Monitor, which records your blood pressure for 24 hours
• Cardiac event monitors, which continuously record the rhythm and electrical activity of your heart
• Cardiac Catheterisation also known as an angiogram allows your doctor to look inside your coronary arteries and find out where and how severe any narrowed areas are.  A right heart catheterisation determines how well the right side of the heart is pumping and to measure the pressures in the heart and lungs. This is particularly important in some people with holes in the heart or raised blood pressure in the lungs (pulmonary artery hypertension)
• Exercise ECG is recorded while you are walking on a treadmill. The aim of the test is to see how your heart works when you are more active. It is particularly useful to look at blood pressure, symptoms and ECG changes
• Cardio Pulmonary Exercise Testing (CPET or CPEx) is a non-invasive simultaneous measurement of the cardiovascular and respiratory system during static bicycle exercise to assess your exercise capacity. The advantages over the treadmill test are that it gives more information about the efficiency of your heart and circulation
• Cardiac CT scan produces multiple x-ray images of your heart from different angles, which the doctor can then see on a computer screen
• Cardiac MRI scan is a non-invasive test that uses an MRI machine to create magnetic and radio waves to create clear pictures showing the inside of your heart. Unlike an X-ray, an MRI scan does not use radiation. It is quite a noisy test and it involves lying in a tunnel.  Most people cope with it very well but sometimes those who get a bit claustrophobic may need to have some sedation beforehand. Rarely people just cannot cope with it. We understand if you are someone who really cannot tolerate it. We prefer it because it gives us vital information with X rays or radiation. Some people with pacemakers cannot have the investigation (because the pacemaker leads overheat). Increasingly the leads and batteries of pacemakers allow MRI scans (called MRI conditional pacemakers or devices)
• MIBI scan (myocardial perfusion scan) uses a medication to simulate exercise for your heart and a small amount of radioactive substance to create images which show blood flow to your heart muscle as it exercises
• Pulmonary function testing look at how well your lungs work. Spirometry shows how well you breathe in and out
• Transoesphageal echo (TOE) is an alternative way to gain Echo pictures. A specialised probe containing an ultrasound transducer at its tip is passed into the gullet tube (oesphagus). This is carried out under sedation in the cardiology department and allows more detailed imaging of your heart if required