Tests

Tests carried out to diagnose heart disease can be broadly divided into three categories: non-invasive, invasive and cardiac imaging. They help to form a clinical diagnosis of the type of heart disease and develop an appropriate management plan.

Non-invasive investigations

Non-Invasive Investigations

Echocardiogram (ECHO)

What is an Echocardiogram (TTE)?

An echocardiogram (sometimes abbreviated to the word “Echo”) is an ultrasound scan that shows a detailed view of the structures of your heart to see how well your heart is working.

A probe is used to send out sound waves to the heart, which are reflected by the muscles and tissues in your heart. This builds up a picture of the anatomy of the heart and blood flow through the heart.

An echocardiogram is useful for diagnosing enlarged left or right sides of the heart, problems with the heart valves and to investigate the causes of heart murmurs or heart attacks.

An echocardiogram is usually performed using a trans-thoracic approach (probe on the chest wall) as described above, this is called a TTE or transthoracic echocardiogram. But we may occasionally need to do this via a trans-oesophageal approach, where a probe is passed into the oesophagus, and this is called a TOE or trans-oesophageal echocardiogram.

Carrying out an Echocardiogram

An Echocardiogram is a painless test that usually takes 30-45 minutes.

You will be asked to remove your clothes from your upper body and lie on your left-hand side.

The cardiac sonographer performing the test will move the probe around your chest to give different views of your heart. You may hear sounds as Doppler signals are used to assess the flow of blood.

What if I need a bubble contrast Echocardiogram?

A bubble contrast echocardiogram (also known as a ‘Bubble Echo’) is a non-invasive test using ultrasound to look at your heart.

Unlike an echocardiogram, a bubble contrast echocardiogram uses imaging ultrasound to look for abnormal shunting of blood in the heart such as PFO or ASD (‘holes’ in the heart).

Risks factors of Echocardiogram

Rubbing the probe on your chest may be a little uncomfortable. Please tell your cardiac sonographer if it is uncomfortable in any way. Please also inform the sonographer if you have any gel allergies.

Ambulatory ECG Monitoring

What is Ambulatory ECG?

Ambulatory Electrocardiographic (ECG) monitoring is used to help diagnose intermittent and infrequent cardiac arrhythmias over a long period of time.

It can be used for 24 hours, 48 hours or up to 1 week. It records your heart rhythm over longer periods of time to greatly increase the odds of capturing and recording this intermittent, but significant, arrhythmia.

Reasons for having Ambulatory ECG?

Ambulatory ECG is most commonly used when a person has symptoms that could be explained by an irregular heartbeat.

These symptoms often include the following:

Syncope
Near syncope
Sudden light headedness
Recurrent palpitations

Ambulatory ECG monitoring is routinely used to:

Look for episodes of asymptomatic atrial fibrillation in those who have previously suffered a stroke with unknown causes.
Assess how effective a previous ablation procedure has been.
Screen for potentially dangerous arrhythmias in people with conditions known to produce such arrhythmias.
Look for signs of asymptomatic heart disease when there are signs that the heart intermittently is being starved of oxygen in those with known coronary artery disease.

Results of an Ambulatory ECG

The ECG monitor records all your heart beats over a specific period of time. It takes a little while to go through all the data collected to establish if the rhythm of your heart is normal or not.

Once your cardiologist has been through your results, they will be explained to you and will make you aware of any next steps if needed.

Remote Ambulatory ‘Patch’ ECG

We are also able to provide remote ambulatory ECG monitoring using a small ECG ‘patch’ device. This can be sent to you in the post, and you can download a smartphone app to input any of your symptoms. This patch can then be sent to us in the post for analysis. These small patch devices are very wearable and the analysis can normally be turned around within 72 hours and even sooner if required. The remote service also has the advantage of avoiding more than one visit as you can be seen by the cardiologist with the results of your ambulatory ECG at the first visit.

Electrocardiogram (ECG)

What is an ECG?

An ECG or electrocardiogram is a simple test to check your heart rhythm and electrical activity.

Sensors are attached to the skin and used to detect the electrical signals produced by each heartbeat.

Signals are recorded by a machine and looked at by a consultant cardiologist to see if they are unusual.

It is important to note that an electrocardiogram is very different to an echocardiogram which is an ultrasound scan used to look at the heart.

Why would I need an ECG?

An ECG would typically be used alongside other tests to help diagnose and monitor conditions of the heart.

If there are any signs or symptoms of possible heart problems, it will also be used to detect these. These symptoms could include chest pain, palpitations, dizziness, and shortness of breath.

An ECG can help detect:

Arrhythmias
Coronary heart disease
Heart attack
Cardiomyopathy

What can I expect when having an ECG?

You will lie on a coach with your upper body clothing removed. Sticky pads will be attached across your chest and on your arms and legs. The machine will read the electrical signals inside your heart. The results can be interpreted by a cardiac physiologist and your cardiologist.

Risk factors with an ECG

An ECG is a quick and painless test with no electricity being put into your body.

As the sensor pads are sticky, there may be some discomfort when these pads are removed. Some people may notice a mild rash where the sticky pads are removed, but this should subside after a few hours.

Exercise Tolerance Testing (ETT)

What is Exercise Tolerance Testing?

An exercise tolerance test (ETT) is the same as an electrocardiogram (ECG) test but recorded while you are exercising.

This test assesses how well your heart works when you are doing something active. During exercise, your heart needs more blood and oxygen and is therefore working harder.

The test will show if there is a lack of blood through the arteries that supply the heart.

What can I expect from an Exercise Tolerance Test?

An exercise tolerance test usually takes between 10-15 minutes and is far more valuable if you try to walk for as long as possible.

Before you come for your test you will be asked to wear appropriate clothing and footwear. Ensure you don’t eat any big or heavy meals before taking this test.

Small sticky electrode pads will be placed onto your chest which are connected to wires. A cardiac physiologist will take your blood pressure at the start of the test, before asking you to cycle on an exercise bike. You will be asked to continue cycling until enough information has been obtained.

Your results will be sent to you or the person who referred you, and your consultant (if available) will be able to provide you with an informal result straight after your test.

Stress Echocardiogram

What is a Stress Echocardiogram?

A stress echocardiogram, also known as a stress echo, is a test to determine how well your heart and blood vessels are working.

Your sonographer will record your blood pressure and heart rhythm before you start your test. A resting echocardiogram will also be done.

During the test you will be exercising on a bike while monitoring your blood pressure and heart rhythm. It may be that dobutamine is used to increase your heart rate.

When your heart rate reaches peak levels, ultrasound images will be taken of your heart to determine whether your heart muscles are getting enough blood and oxygen when exercising.

Why do I need a Stress Echocardiogram?

Your cardiologist may order a stress echo if you have experienced any chest pains relating to potential coronary artery disease or a heart attack.

If you are in cardiac rehabilitation, the test will be able to show your consultant how much exercise you can safely tolerate. It can also show how well any heart medication or treatments are working.

Risks with a Stress Echocardiogram

This non-invasive test is safe, but whilst rare, complications that can occur include:

An abnormal heart rhythm
Dizziness
Allergy to any contrast agent given

Cardiopulmonary Exercise Testing (CPET)

What is a CPET?

A cardiopulmonary exercise test (CPET) is a non-invasive ECG test used to assess the performance of the heart and lungs when exercising and when resting. The test is carried out whilst you are exercising in order to detect any changes in your heart.

During the test, your blood pressure will be measured at the same time. You will be asked to wear a mask to assess Oxygen (O2) and Carbon Dioxide (CO2) saturation levels.

Why would I need a CPET?

A CPET is used to test patients who have shown signs of heart or lung disease. In addition, this test may be used to assess patients currently in rehabilitation from major illness, or to test patients scheduled for major surgery.

What can I expect from a CPET?

A CEPT usually takes about 40 minutes and is far more valuable if you give it your maximum effort.

Before you come for your test you will be asked to wear appropriate clothing and footwear. Ensure you don’t eat any big or heavy meals before taking this test.

Small sticky electrode pads will be placed onto your chest which are connected to wires, and you will be asked to wear a breathing mask. Your consultant will take your blood pressure before you start the test. You will then me asked to sit upright on an exercise bike. The pace of the bike will be slowly increased, and you will be asked to continue the test until enough information has been obtained. The breathing mask will measure each breath to assess how the body is performing as well as the capacity and strength of the lungs. The sticky electrodes will monitor your heart rate.

Your results will be sent to you, or the person who referred you, but your consultant (if available) will be able to give you an informal result straight after your test. It is a complex test that measures a multitude of cardio-respiratory parameters and will require specialist reporting.

Carotid Ultrasound

What is a Carotid Ultrasound?

Ultrasound is a safe and painless way of producing an image of the inside of the body using sound waves. Carotid ultrasound uses these sound waves to produce images of the carotid arteries in the neck which carries blood from the heart to the brain.

When performing a carotid ultrasound, a doppler will be used – this is a technique that evaluates blood flow through a blood vessel. The doppler will pinpoint the location of a blockage or narrowing of the carotid arteries, also known as stenosis, a condition that can lead to cause a stroke.

Why would I need a Carotid Ultrasound?

You may need a carotid ultrasound if you have a carotid bruit – an abnormal sound in the neck, heard with a stethoscope. You may also have one in preparation for coronary artery bypass surgery.

Other reasons to consider a carotid ultrasound include:

Diabetes
High blood pressure
Smoking
Elevated blood cholesterol
A family history of stroke or heart disease
Recent history of stroke

Doppler ultrasound may also help to see:

Blockages to blood flow including clots
Narrowing vessels
Tumour or congenial vascular malformations
Reduced or absent blood flow to various organs

Myocardial Perfusion Scanning (MPS)

What is Myocardial Perfusion Scanning (MPS)?

A myocardial perfusion scan (MPS) shows blood flow to the heart using a small amount of radioactive substance to create images. The myocardial perfusion looks at the pumping action of your heart and the flow of blood to your heart. This can help in diagnose coronary heart disease or show the benefits of having a coronary angioplasty or coronary bypass surgery.

What happens during Myocardial Perfusion Scanning?

A small amount of radioactive substance is injected into your blood stream so that your blood flow can be detected by a special camera.

The camera is positioned close to your chest to take pictures of different parts of the heart, very similar to an x-ray. This test is done in two parts – when your heart is stressed, and when your heart is resting.

To stress the heart, before you are injected you will be asked to exercise on a piece of exercise apparatus. If you cannot exercise, your consultant may administer some medicine to increase your heart rate instead.

An hour later, after you’ve eaten and drank to clear the radiation from your system, you will go back and be injected again. Whilst you are lying on the bed, with a rested heart, the camera then collects the same images.

Risks of Myocardial Perfusion Scanning

Whilst it is a small amount, you will be exposed to some radiation during this test. There are usually no side effects from this type of scan, but you may feel a bit breathless with the medicines given.

There are a few factors to remember:

Don’t have any food or drink containing caffeine at least 24-hours before the test.
You need to lie as still as possible for this test to be effective.
You must tell the consultant if you are pregnant or breastfeeding.

Invasive Investigations

Transoesophageal Echocardiogram (TOE)

What is a Transoesophageal Echocardiogram (TOE)?

A Transoesophageal Echocardiogram (sometimes called a ‘TOE’) is a test using ultrasound to produce moving images of your heart. It shows both the structure of your heart and how well it’s working.

This type of ultrasound can also be used as guide for a surgeon whilst undergoing heart surgery.

What happens during a TOE?

Your cardiologist will pass an ultrasound probe into your oesophagus. As you will be awake for this procedure, your doctor may give you a sedative to help you relax. The sedative will be given through a cannula in your arm.

You will be asked not to eat for 6 hours before the investigation and have only sips of water until 2 hours before. After that you should have NOTHING to eat or drink.

Your cardiologist will ask you to lie on your left-hand side on a bed. Your throat will be sprayed with local anaesthetic and a probe will be guided down your throat. Your consultant will ask you to swallow to help the probe into your oesophagus. The probe will send out sound waves and pick up returning echoes. These are converted into pictures of the inside of your heart and constantly updated on the monitor so the scan can show the movements.

Risks with a TOE

TOE is a safe procedure.

There are also a few complications with having this type of test including:

Soreness in the throat- this is common and short lasting
More rarely:
- Damage or tear of your oesophagus
- Allergic reaction to the sedative
- Inhaling the contents of your stomach during the test

Your cardiologist will take you through the details and any risks before your procedure.

Invasiv investigtions

Reveal LINQ Implant Device

What is a Reveal LINQ Implant Device?

A LINQ device is a cardiac device, as small as a USB stick, which is implanted under the skin and remains there over a long period of time. This type of device is commonly used for patients who experience fainting or sporadic palpitation symptoms.

What happens when getting a Reveal LINQ Implant Device fitted?

Implanting the device involves a small surgical procedure under local anaesthetic on the left side of your chest. The entrance wound does not need any form of closure. The device remains in the same position for up to four years.

If you experience fainting or sporadic palpitation symptoms, the device will record this. These results will then form a picture over a period of time which can be analysed. Your consultant cardiologist can then make a diagnosis before creating a treatment plan.

Coronary Angiography

What is a Coronary Angiogram?

A Coronary Angiogram uses X-ray imaging to see your hearts blood vessels. Coronary Angiograms are usually done as part of a group of procedures known as heart catheterisations that diagnose and treat heart and blood vessel conditions. A Coronary Angiogram is the most common procedure in this group of tests. It can show the consultant what’s wrong with your blood vessels and can:

Show how many of your coronary arteries are blocked
Pinpoint where blockages are
Show how much of the blood flow is blocked through your blood vessels
Check previous coronary bypass surgery

What happens during a Coronary Angiogram?

A small incision will be made in the wrist or the groin, and a small plastic pipe (called a catheter) is placed in an artery under local anaesthetic. If the groin is used the catheter is placed in the femoral artery, if the wrist is used then the radial artery is used.

The catheter will be guided to your heart. A dye will then be injected through the catheter which may give you a warm or flushing feeling. The dye makes it easy to see the catheter on x-ray images. As the dye moves through your blood vessels, your consultant can observe the flow and easily identify any blockages or constricted areas.

An angiogram usually only takes about 20-30 minutes, although it is can take longer if additional tests are done at the same time. Sometimes detailed pressure readings are needed, and a further catheter is inserted (Left and Right Heart Catheter)

At the same time, coronary physiology can be assessed by looking at the pressure drop across any narrowing that is seen, with a Pressure Wire study (FFR or Fractional Flow Rate).

Sometimes additional imaging is done at the same time to look at the narrowing in more detail:

Intravascular Ultrasound (IVUS)
Optical Coherence Tomography (OCT)

At the end of the procedure, the puncture in the artery will be sealed with a plug or band to avoid it bleeding.

Why do I need a Coronary Angiogram?

You may be referred for a Coronary Angiogram by your doctor if you have any of the following:

Symptoms of coronary artery disease
Pain in your chest, jaw, neck or arm
New or increase chest pains
A heart valve problem requiring surgery
Abnormal heart stress test results
A heart defect when you were born

Risks of a Coronary Angiogram

A Coronary Angiogram is a safe procedure. There can be risks with most procedures done on your heart and blood vessels, and with a coronary angiogram the risks include:

Heart attack
Stroke
Exposure to radiation
Injury to catheterised artery
Irregular heart rhythms
Allergic reaction to the dye
Kidney damage
Excessive bleeding
Infection

Cardiac Imaging

CT Coronary Angiography (CTCA)

What is a CTCA?

A CT Coronary Angiography (CTCA) is a scan that takes pictures of the coronary arteries of a beating heart. A liquid contrast agent is injected into a vein in the arm to increase the density of the blood in the vessels. This allows the inside and outside structure of the blood vessels to be seen more clearly on the CT scan.

A CTCA is not the same an an invasive coronary angiogram.

Why would I need a CTCA?

A CTCA is predominantly used to check for narrowed or blocked arteries in your heart, but it can also be used to check your heart for various conditions. It can be used to look at structures around the heart and plan for more complex structural heart interventions.

Are there any risks with having a CTCA?

Due to the nature of an X-ray, you will be exposed to some radiation during the test. The amount of radiation will depend on the machine and the type of test performed. It is essential that you speak to your consultant cardiologist if you are pregnant.

In addition, contrast X-ray dye that is given that can affect the kidneys and in rare cases can cause an allergic reaction.

Cardiac MRI

What is a Cardiac MRI Scan?

A Cardiac MRI scan is a type of scan that uses magnetic fields and radio waves to produce a detailed image of the heart.

A Cardiac MRI can be used to help diagnose conditions, create a treatment plan, and assess how effective a current or previous treatment plan has been.

The test can provide information on structure and function. It can also be used as a stress test.

What happens during an MRI Scan?

Whilst the scan is happening, you will be asked to lie flat on a bed that moves in and out of the scanner. As you will be having a scan of your heart, you will be moved into the scanner headfirst.

The scanner can be quite loud at times and you will be given earplugs or headphones to wear during your scan.

The most important part of an MRI scan is to keep as still as possible.

The scan will last anywhere between 15 minutes and up to 45 minutes, depending on how many images need to be taken.

Risks with an MRI Scan

An MRI is both painless and safe. You are not being exposed to any x-ray radiation.

The only issue that might occur is if you have claustrophobia, but with the support of the radiographer, this is usually very easily manageable.

There has been no evidence to suggest that the magnetic fields and radio waves used during an MRI scan pose a risk to the human body.

An MRI may not be recommended in certain situations such as if you have a metal object in your body such as a pacemaker. Although some newer pacemakers are MR compatible. Your cardiologist will be able to advise you.