ECG and Spirometry

What is an ECG Test?

An electrocardiogram (ECG) is a medical test that detects cardiac (heart) abnormalities by measuring the electrical activity generated by the heart as it contracts. 

The ECG machine that records the patient’s ECG is called an Electrocardiograph.

What are the Benefits of an ECG Test?

Your doctor may use an electrocardiogram to detect:

• Irregularities in your heart rhythm (arrhythmias)
• Detect blocked or narrowed arteries in your heart (coronary artery disease) that may cause chest pain or heart attacks,
• Show structural problems with your heart's chambers
• Help manage your heart health after a previous heart attack
• Manage the effectiveness of ongoing heart disease treatments, (eg: pacemaker functioning)

How Does an Electrocardiograph Work?

The electrocardiograph records the electrical activity of the heart muscle as it's various muscles and values open and shut.

These impulses are displayed as a data trace on a screen or paper. This data is then interpreted by a medical practitioner.

ECGs from healthy hearts have a characteristic shape. Any irregularity in the heart rhythm or damage to the heart muscle can change the electrical activity of the heart so that the shape of the ECG is changed.

Why is an ECG Diagnostic Test Performed?

A doctor may recommend an ECG for people who could be at risk of heart disease. Some reasons a doctor would request this test are:

• family history of heart disease, 
• smoking
• overweight,
• diabetes, 
• high cholesterol, or
• high blood pressure. 

ECGs are often performed to monitor the health of people who have been diagnosed with heart problems, to help assess artificial cardiac pacemakers or to monitor the effects of certain medications on the heart.

Heart Disease Symptoms

If a patient is experiencing symptoms such as:

• chest pain
• shortness of breath
• dizziness
• fainting, or 
• fast or irregular heartbeats (palpitations). 

an ECG may also recommend.

What Can an ECG Test Help Diagnose?

The results of your ECG will determine what treatment you need if any. 

Some heart problems that can be diagnosed by ECG include: 

• enlargement of the heart
• congenital heart defects involving the conducting (electrical) system
• abnormal rhythm (arrhythmia) – rapid, slow or irregular heartbeats 
• damage to the heart such as when one of the heart’s arteries is blocked (coronary occlusion)
• poor blood supply to the heart
• abnormal position of the heart
• heart inflammation – pericarditis or myocarditis
• cardiac arrest during the emergency room or intensive care monitoring 
• disturbances of the heart’s conducting system
• imbalances in the blood chemicals (electrolytes) that control heart activity
• previous heart attacks.

A person with heart disease may have a normal ECG result if the condition does not cause a disturbance in the electrical activity of the heart. Other diagnostic methods may be recommended if heart disease is suspected.

What Other Diagnostic Information Can an ECG Show?

Your doctor will look for a consistent, even heart rhythm and a heart rate between 50 and 100 beats a minute. 

Having a faster, slower or irregular heartbeat provides clues about your heart health, including:

• Heart rate. Normally, the heart rate can be measured by checking your pulse. An ECG may be helpful if your pulse is difficult to feel or too fast or too irregular to count accurately. An ECG can help your doctor identify an unusually fast heart rate (tachycardia) or an unusually slow heart rate (bradycardia).
• Heart rhythm. An ECG can show heart rhythm irregularities (arrhythmias). These conditions may occur when any part of the heart's electrical system malfunctions. In other cases, medications, such as beta-blockers, cocaine, amphetamines, and over-the-counter cold and allergy drugs, can trigger arrhythmias.
• Heart attack. An ECG can show evidence of a previous heart attack or one that's in progress. The patterns on the ECG may indicate which part of your heart has been damaged, as well as the extent of the damage.
• Inadequate blood and oxygen supply to the heart. An ECG done while you're having symptoms can help your doctor determine whether chest pain is caused by reduced blood flow to the heart muscle, such as with the chest pain of unstable angina.
• Structural abnormalities. An ECG can provide clues about enlargement of the chambers or walls of the heart, heart defects and other heart problems.

Preparation For an ECG Test

Preparing for an ECG Test you will:

• Not need to restrict food or drink. 
• Ensure the doctor is aware of your regular medications, 
• Communicate any allergies to adhesive tapes or latex.
• Wear suitable clothing (separate top and bottom) to allow easy access to the chest 

During an ECG Test

During an ECG Test will:

• Where necessary the selected electrode sites may be shaved.
• Electrodes (sensors) are attached to the chest, arms and legs with suction cups or sticky gel. 
• The electrodes detect electrical currents generated by the heart – these are measured and recorded by the electrocardiograph.
• Last a few minutes, and you should be able to go home soon afterwards 

Results

An ECG recording machine will usually show your heart rhythm and electrical activity as a graph displayed electronically or printed on paper.

For an ambulatory ECG, the ECG machine will store the information about your heart electronically, which can be accessed by a doctor when the test is complete.

You may not be able to get the results of your ECG immediately. The recordings may need to be looked at by a specialist doctor to see if there are signs of a potential problem. 

Other tests may also be needed before it's possible to tell you whether there's a problem.

You may need to visit the hospital, clinic or your GP a few days later to discuss your results with a doctor.

Spirometry Lung Function Test

What is a Spirometry Test

Spirometry is a simple test used to help diagnose and monitor certain lung conditions by measuring how much air you can breathe out in one forced breath.

It's carried out using a device called a Spirometer, which is a small machine attached by a cable to a mouthpiece.

Who Have Spirometry Tests?

Spirometry is used to diagnose 

• asthma, 
• chronic obstructive pulmonary disease (COPD), and
• other conditions that affect breathing. 

Spirometry may also be used periodically to monitor your lung condition and check whether a treatment for a chronic lung condition is helping you breathe better.

What Can a Spirometry Test Diagnose?

A lung function test using Spirometry can help diagnose:

• Asthma – a long-term condition in which the airways become periodically inflamed (swollen) and narrowed
• Chronic Obstructive Pulmonary Disease (COPD) – a group of lung conditions where the airways become narrowed
• Cystic Fibrosis – a genetic condition in which the lungs and digestive system become clogged with thick, sticky mucus
• Pulmonary Fibrosis – scarring of the lungs

If you have already been diagnosed with one of these conditions, spirometry may be carried out to check the severity of the condition or see how you're responding to treatment.

What Can a Spirometry Test Measure?

A spirometer measures the amount of air you can breathe out in one second and the total volume of air you can exhale in one forced breath.

These measurements will be compared with a normal result for someone of your age, height and sex. This comparison can indicate if your lungs aren't working properly.

The measurements will also show whether any area of your lungs is "obstructed", "restricted", or a combination of the two.

Types of Lung Disorders That Spirometry Can Detect

Lung disease can take many forms but generally, Spirometry can help detect either

• Obstructive Airways Disease – where your ability to breathe out quickly is affected by a narrowing of the airways, but the amount of air you can hold in your lungs is normal (such as in asthma or COPD)
• Restrictive Lung Disease – where the amount of air you can breathe in is reduced because your lungs are unable to fully expand (such as in pulmonary fibrosis).

Preparation For a Spirometry Test

While you'll be told about anything you need to do to prepare for the test. Common preparation for a Spirometry Test includes:

• You may need to pause before the test any bronchodilator medication (medicines, usually inhaled, that help relax and widen your airways) but only as directed by your doctor 

Things to avoid before a Spirometry Test include:

• Smoking for 24 hours before the test, 
• Drinking alcohol, 
• Strenuous exercise 
• Eating large meals a few hours your test.

It's best to wear loose, comfortable clothing on the day of the test.

Possibly ask yourself if you have any concerns or specific worries relating to your breathing difficulties, as providing a more complete picture can help in creating a better solution if required.

During a Spirometry Test

A spirometry test requires you to breathe into a tube attached to a machine called a spirometer. Before you do the test, a nurse, a technician or your doctor will give you specific instructions. Ask questions if something is not clear. 

Doing the test correctly is necessary for accurate and meaningful results.

During a spirometry test you will:

• be seated with a clip placed on your nose to close your nostrils,
• be asked to take a deep breath and breathe out as hard as you can for several seconds into the tube. 

It's important that your lips create a seal around the tube so that no air leaks out.

The test is run at least three times to ensure consistent results. If the test results vary too much, you will be asked to repeat the test. 

The highest value among the three close test results is used as the final result.

The entire process usually takes less than 15 minutes.

Your doctor may give you an inhaled medication to open your lungs (bronchodilator) after the initial round of tests. 

You'll need to wait 15 minutes and then do another set of measurements. 

Your doctor then can compare the results of the two measurements to see whether the bronchodilator improved your airflow.

Results - how long and

The person carrying out the test won't usually be able to give you your results immediately.

The results will need to be looked at by a specialist first and will then be sent to the doctor who referred you for the test, who will discuss them with you a few days later.