If your doctor thinks you may be at risk of developing coronary heart disease (CHD), they may carry out a risk assessment for cardiovascular disease, heart attack or stroke.
Your doctor will ask about your medical and family history, check your blood pressure and do a blood test to assess your cholesterol level.
Before having the cholesterol test, you may be asked not to eat for 12 hours so there is no food in your body that could affect the result. Your GP or practice nurse can carry out the blood test and will take a sample either using a needle and a syringe or by pricking your finger.
Your GP will also ask about your lifestyle, how much exercise you do and whether you smoke. All these factors will be considered as part of the diagnosis.
To confirm a suspected diagnosis you may be referred for more tests. A number of different tests are used to diagnose heart-related problems including:
- electrocardiogram (ECG)
- blood tests
- coronary angiography
- radionuclide tests
- magnetic resonance imaging (MRI)
An ECG records the rhythm and electrical activity of your heart. A number of electrodes (small, sticky patches) are put on your arms, legs and chest. The electrodes are connected to a machine that records the electrical signals of each heartbeat.
Although an ECG can detect problems with your heart rhythm, an abnormal reading does not always mean that there is anything wrong, nor does a normal reading rule out heart problems.
In some cases you may have an exercise ECG test or 'stress test'. This is when an ECG recording is taken while you are exercising (usually on a treadmill or exercise bike). If you experience pain while exercising, the test can help to identify whether your symptoms are caused by angina, which is usually due to CHD.
An x-ray may be used to look at the heart, lungs and chest wall. This can help to rule out any other conditions which may be causing your symptoms.
An echocardiogram is similar to the ultrasound scan used in pregnancy. It produces an image of your heart using sound waves. The test can identify the structure, thickness and movement of each heart valve and can be used to create a detailed picture of the heart.
During an echocardiogram you will be asked to remove your top and a small handheld device, called a transducer, will be passed over your chest. Lubricating gel is put onto your skin to allow the transducer to move smoothly and make sure there is continuous contact between the sensor and the skin.
In addition to cholesterol testing, you may need to have a number of blood tests that are used to monitor the activity of the heart. These include cardiac enzyme tests, which can show whether there is damage to the heart muscle, and thyroid function tests.
Coronary angiography, also known as a catheter test, is usually performed under local anaesthetic. As well as providing information about your heart's blood pressure and how well your heart is functioning, an angiogram can also identify whether the coronary arteries are narrowed and how severe any blockages are.
In an angiogram, a catheter (flexible tube) is passed into an artery in your groin or arm and it is guided into the coronary arteries using X-rays. A dye is injected into the catheter to show up the arteries supplying your heart with blood. A number of X-ray pictures are taken, which will highlight any blockages.
A coronary angiogram is a relatively safe procedure and serious complications are rare. The risk of having a heart attack, stroke or dying during the procedure is estimated at about one or two in every 1,000. However, after having a coronary angiogram, you may experience some minor side effects including:
- a slightly strange sensation when the dye is put down the catheter
- a small amount of bleeding when the catheter is removed
- a bruise in your groin or arm
Radionuclide tests are used to diagnose CHD. They can also indicate how strongly your heart pumps and show the flow of blood to the muscular walls of your heart. Radionuclide tests provide more detailed information than the exercise ECG test.
During a radionuclide test, a small amount of a radioactive substance, called an isotope, is injected into your blood (sometimes during exercise). If you have difficulty exercising, you may be given some medication to make your heart beat faster. A camera placed close to your chest picks up the radiation transmitted by the isotope as it passes through your heart.
Magnetic resonance testing (MRI)
An MRI scan can be used to produce detailed pictures of your heart. During an MRI scan, you lie inside a tunnel-like scanner that has a magnet around the outside. The scanner uses a magnetic field and radio waves to produce detailed images.