Non-Invasive Diagnostics and Cardiac Physiology

The Non-Invasive Diagnostics Unit offers a wide range of investigations for patients with suspected cardiac problems in both the outpatient and inpatient setting.

Cardiac physiologists are supported by consultant cardiologists in the provision and interpretation of the various tests. The more complex imaging is undertaken by cardiologists with expertise in imaging and by radiologists. They provide peri-procedural imaging to both interventional and surgical procedures where required.

Following a test, the consultant will either discuss the results with you in clinic or send the report to your GP.

The range of diagnostic tests and imaging designed to assess the structure and function of the heart include:

Electrocardiogram (ECG)

An ECG monitors the electrical activity of your heart. It is a very quick test and gives a good general overview of the state of your heart. Almost all patients attending as an outpatient or an inpatient will receive an ECG test.

Ambulatory ECG monitoring-Holter recorders, loop recorders, cardiomemos

Holter monitors are used to record the electrical activity of the heart, like an ECG but over a longer period of time. A Holter device is connected to electrodes placed on the chest for periods between 24 hours and seven days. Analysis of the recordings helps identify unusual rhythms in the heart that may only occur during certain activities.

  • 24-hour blood pressure monitoring
Exercise Tolerance Test (ETT)

Sometimes symptoms or unusual heart rhythms only appear when the heart is working hard (‘stressed’). An Exercise Tolerance Test (ETT, sometimes called an Exercise Stress Test) involves walking on a treadmill while staff monitor your ECG (see above), blood pressure and heart rate. ETTs can be quite tiring as the aim is to safely stress the heart as much as possible. Our staff will always make sure you are feeling ok throughout the test, and if at any point you feel unable to continue then the test can be stopped.

Tilt testing

These are designed to assess the cause of faintness or dizziness. While lying on a table, you will be raised into an upright position; this is to try to induce your symptoms. Your ECG (see above) and blood pressure are monitored throughout and any unusual readings will be compared with your symptoms.

  • Transthoracic echocardiography (structure and function of the heart chambers and valves) - 2 dimensional and 3 dimensional studies
  • Trans-oesophageal echocardiography (diagnostic and also used during interventional procedures)
  • Stress Echocardiograms
  • Cardiac Computerised Tomography (Cardiac-CT), Cardiac Magnetic Resonance Imaging (Cardiac-MRI) and Radio-isotope studies (nuclear medicine)