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What is an Echocardiogram with Bubble Study?
An echocardiogram (echo) is a routine ultrasound scan that uses sound waves (ultrasound) to produce real time images of your heart. You may have already had a routine transthoracic echocardiogram where a handheld probe is moved across your chest and the images are displayed on the echo machine screen. This gives information about various structures of the heart.
An echocardiogram with bubble study (bubble study for short) is similar but can help to identify a flap, or a hole, between the top two chambers (the atria) of the heart. It is a safe procedure that takes about 30 minutes.
What are the benefits of an Echocardiogram with Bubble Study?
Normally blood flow on the right side of the heart (deoxygenated blood), which is a lower pressure, does not communicate or mix with blood on the left side of the heart (oxygenated blood) which is a higher pressure.
However, with conditions such as Patent Foramen Ovale (PFO) or an Atrial Septal Defect (ASD) there is a connection between these two chambers. This connection can mean that blood flow from the right side can cross to the left side.
An echocardiogram has limited ability in detecting a PFO or ASD especially small ones. An echocardiogram with bubble study is more effective at finding them and is more precise in grading the severity of the shunt from right to left.
Preparing for the Echocardiogram with Bubble Study
There is no special preparation for the scan. You can eat and drink as normal and take all your medications as you usually would.
Before the Echocardiogram with Bubble Study
When you arrive at the Cardiac Catheter Lab please report to reception where the reception staff will check you in and ask you to take a seat in the waiting area. When the nurse is ready for you, they will call you through and prepare you for the procedure.
You will be asked to remove the clothes from your upper body and change into a hospital gown with opening at the front. You then lie on a bed and a cannula will be inserted in your arm. Three ECG leads are attached to your chest to monitor your heart rhythm during the scan.
You will be asked to lie on your left side and the lights will be dimmed. You may also be asked to raise your left arm.
During the Echocardiogram with Bubble Study
Firstly, the Consultant will obtain a few images before the bubble study begins. To obtain these images they will put a gel on your chest and press the ultrasound probe firmly against your chest.
Once this is done the bubble study can be performed. This is done by injecting agitated saline solution into your vein via the cannula. The agitated saline creates small bubbles which travel to the right side of your heart.
The Consultant, while taking images, will also ask you to ‘strain down’ to increase pressure in the right side of your heart. Doing this can temporarily open a PFO or ASD allowing the bubbles to cross from right to left. Straining down involves trying to exhale forcefully against a closed mouth and you will be shown how to do this. The injection of the agitated solution together with the straining manoeuvre and image taking will be done several times.
After the Echocardiogram with Bubble Study
Once completed your cannula will be removed. There are no restrictions on what you can do after the scan. It most cases it should be possible for the Consultant carrying out the scan to inform you of the result. The results are sent to the doctor who referred you.
Patent Foramen Ovale (PFO)
A foramen ovale (oval hole) is present in everyone before birth. In about 25% of the population, it does not close completely after birth and is then known as a patent foramen ovale and is like a flap of tissue. It is quite common and often remains undetected and does not cause any problems.
If a blood clot forms in a vein, it can potentially pass through the PFO and travel to the brain causing a stroke. Some evidence suggests that PFO’s might be responsible for strokes when no other cause can be found. This is often referred to as a cryptogenic stroke – a stroke with unknown cause.
If you’re relatively young, and have had a stroke, without obvious risk factors to cause the stroke, and other tests have failed to find a cause then a bubble study may be performed to help identify if a PFO is present.
If a PFO is identified further investigations may be recommended. Potential treatments such as blood thinners and PFO closure are discussed with your referring Stroke Consultant.
Atrial Septal Defect (ASD)
A bubble study may also help to identify a different type of opening between the two top chambers of the heart known as atrial septal defect. This is sometimes referred to as a hole in the heart.
These are usually detected and repaired in childhood but may not be found until adult life. Depending on the size of the ASD it may need to be closed to prevent strain on the heart and heart failure over time.
If you have any questions before your test, please ring the Cardiac Bookings Office on 03006 133337.
The procedure takes place in the Cardiac Catheter Lab Department.
Please note that this is about 400 metres from the Main Entrance so please allow extra time to get here and for parking.
If you think you will not be able to walk this far then please use a wheelchair (there are some available in the Main Entrance) or ask at Reception for a Porter to take you.
Contact us
If you have any queries relating to this information, please contact the Cardiology service.
About this information
Service:
Cardiology
Reference:
C/026
Approval date:
1 August 2025
Review date:
1 August 2028
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Important note
This page provides general information only. It is developed by clinical staff and is reviewed regularly every 3 years for accuracy. For personal advice about your health, or if you have any concerns, please speak to your doctor.