Non-Invasive Tests

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Some of the tests listed below are carried out regularly with someone who has CHD but some are carried out once or not at all. It all depends on the individual or should we say that it all depends of the complexity of the CHD.

Some tests can involve chemicals being injected into the body - invasive - or readings taken externally only - non-invasive. On this page we are concentrating on Non-Invasive Tests, for invasive tests click here

Blood tests - cardiac enzyme tests

Blood samples taken over a series of days can reveal the level of enzymes - proteins that help with chemical actions in the body and are released after a heart attack - in the blood.

Cardiac Event Monitor

The Cardiac Event Monitor is used to detect abnormal heart rhythms. This small device records the heart’s electrical activity (rhythm) at the push of a button. Patients trigger the device when they first begin to feel signs (an “event”) such as:

  • Dizziness
  • Weakness
  • Lightheadedness
  • Heart racing and /or fluttering

The monitor stores the heart rhythm. Later that rhythm is sent via the telephone to the doctor for review. This test allows for on-demand heart monitoring outside the hospital/clinic setting when symptoms are noted and as you go about your normal routine. The test results help guide your doctor to choose treatment options to meet your specific needs.

The monitor, about the size of a deck of cards, is clipped to your waistband. This monitor is connected to a set of wires which attaches to two electrodes worn on your chest (like an EKG). The monitor can be worn for up to 30 days. It is removed during bathing.

CT or CAT scan

High resolution images of the heart, brain and blood vessels are given by X-ray computed tomography (CT) or computerised axial tomographic (CAT) scans.
It is useful to evaluate disease of the aorta - the largest artery in the body and involves little potential risk to patients. In stroke patients, it gives valuable information about the location and extent of brain injury.

Chest x-ray

The chest x-ray is the most commonly performed diagnostic x-ray examination. A chest x-ray makes images of the heart, lungs, airways, blood vessels and the bones of the spine and chest.

An x-ray (radiograph) is a noninvasive medical test that helps physicians diagnose and treat medical conditions. Imaging with x-rays involves exposing a part of the body to a small dose of ionizing radiation to produce pictures of the inside of the body. X-rays are the oldest and most frequently used form of medical imaging.

Doppler Echocardiography

The doppler echocardiography measures the speed of the flow of blood in different parts of the heart.
Occasionally, echocardiography is carried out after the heart is put under stress either with exercise or a drug - stress echocardiography.


An electrocardiogram (ECG) measures the rhythm and electrical activity of the heart.

Small metal patches, called electrodes and set in sticky plaster, are put on the arms, legs and chest and connected by wires to a recording machine.
The test can detect abnormalities of heart rhythm and can tell whether the patient has had a heart attack in the past.

The test has limitations - abnormal readings can have an innocent explanation and some patients with serious heart problems can have a normal ECG.

Exercise ECG

(Otherwise known as exercise stress testing, is an ECG taken while exercising on a treadmill or stationary bicycle).
It is often more accurate than a resting ECG and is used to test whether there is a lack of blood supply through the arteries that go to the heart.
The exercise is made increasingly difficult and blood pressure and breathing are monitored at the same time.
Holter monitoring, also known as 24-hour ECG, involves electrocardiogram recordings taken over 24 hours and can help diagnose palpitations, which occur infrequently and can easily be missed in a short test.
The electrodes are placed on the chest and attached with wires to a small portable tape recorder which is worn on a belt around the waist.
The recorder - the Holter monitor - takes constant or intermittent readings.


A pulse of high frequency, inaudible sound is transmitted through the skin by placing a recorder or probe on the chest wall.
The probe picks up the echoes reflected from various parts of the heart and displays them as an echocardiogram - a picture on a screen.

The recorded waves show the shape, texture and movement of the valves and the size and function of the heart muscle and chambers.

The test can take up to an hour and is painless.

It provides information about disease of the heart muscle for those who have suffered a heart attack or heart failure and to assess people with disease of the heart valves and congenital heart defects.

To view 3d echocardiograms click here

For more information in regard to Echocardiography, please visit Tiny Tickers website

Holtor Monitor

(Also known as an Ambulatory electrocardiography or Electrocardiography - ambulatory. I normally call it a 24 hour tape).

A Holter monitor is a machine that continuously records the heart’s rhythms. The monitor is usually worn for 24 - 48 hours during normal activity.

Small conducting patches known as Electrodes are stuck onto your chest and attached to a small recording monitor. The Holter monitor is carried in a pocket or small pouch worn around your neck or waist. The monitor is battery operated. Whilst wearing the monitor, it records your heart’s electrical activity and you are asked to keep a diary of what activities you do while wearing the monitor (you are usually given a sheet to write down your activities and any palpatations, heart flutter. Once the 24 - 48 hour is up, you return the monitor to your doctor’s office.

The doctor will look at the records and see if there have been any irregular heart rhythms.

It is very important that you accurately record your symptoms and activities so that the doctor can match them with your Holter monitor findings.

Magnetic Resonance Imaging (MRI scan)

Magnetic Resonance Imaging (MRI) produces detailed pictures of internal organs, including the heart and brain.
Patients lie in a short tunnel-like machine which contains a cylindrical magnet. Short bursts of magnetic fields and radio waves create images of parts of the body as required.

MRI can measure the flow of blood through some of the major arteries and can detect abnormal heart function in disorders such as cardiomyopathy (heart muscle disease), coronary heart disease, congenital heart defects and help define the location and extent of brain injury in stroke patients.

Pulse Oximetry

click here to go pulse oximetry

Tilt Table Testing

see mitral valve

Stress Test

see Exercise ECG above.

PLEASE feel free to email us your or your families experiences, we would love to hear from you.

Related Links: notes

Disclaimer: The facts and opinions shown in this article are as accurate and up to date as possible, but are provided as general “information resources”, which may not be relevant to individual persons. This article is not a substitute for individual assessment and always take advice from a doctor who is familiar with the particular person.

Consult you or your child’s physician regard the specific outlook for you or your child..