A non-invasive study typically done with an echocardiogram, a bubble study helps your cardiologist to assess the blood flow and identify potential issues inside the heart.
It is also known as Transcranial Doppler study or contrast echocardiography.
Bubble StudyA bubble study works on the principle of sound waves.
When a sound wave encounters different physical media – gas, and liquid in this case – it bounces around more, creating more “echo waves.” These waves come up on the ECG as increased density.
In a bubble study, a technician sets up an IV line in your arm. A solution is prepared by mixing air with saline, which creates tiny bubbles. This solution is then injected into the vein.
As the fluid circulates to the right side of your heart, your physician can view the increased density produced by the bubbles as they move into the cardiac chambers.
In a healthy functioning heart, the bubble will enter the right atrium and ventricle and goes through the pulmonary artery into your lungs, where the bubbles are filtered out.
In some instances, the bubbles will move into the upper chambers of your heart. This indicates the presence of an abnormal opening – an intracardiac shunt.
This shunt can be caused by patent foramen ovale (PFO), atrial septal defect (ASD), or other causes.
Patent Foramen Ovale (PFO)A common occurrence, patent foramen ovale happens when the hole present in every individual before birth fails to close completely.
PFO is relatively harmless and does not result in any serious medical condition. However, some evidence suggests that PFO can cause certain rare strokes in the absence of any other cause.
Typically, the blood vessels trap tiny clots before it reaches your heart and recirculates into the body. If a clot bypasses your lungs through a PFO, then it can reach the arteries which supply blood to the entire body.
If a clot gets lodged in a vessel carrying blood to the brain, then it can result in a stroke. PFO can be suspected if you get a stroke at a relatively young age and have no apparent risk factors.
While PFO closure can be a solution, many studies claim not much benefit will accrue from closing PFOs since one cannot determine that a PFO was the cause of the stroke.
As a result, drugs that help in preventing clots are the mainstay of a stroke prevention protocol.
Atrial Septal DefectYour cardiologist, during the bubble study, might also detect an atrial septal defect (ASD) - an opening in the septum between the atria.
ASDs are typically discovered in childhood and repaired, but can go unnoticed till later stages in life. Your cardiologist, based on the size of the hole, will suggest closure to prevent any strain and heart failure in later stages.
New Saline SolutionsCurrently, different types of “bubbles” are available in the market. These new bubbles either contain tiny protein particles or phospholipid casings that enclose a gas.
These bubbles are safer and can give a physician better echo images in some instances. However, these agents are highly expensive in comparison to an agitated saline solution.