Can a bubble study be done to detect a patent foramen ovale (PFO) in a pregnant woman?

From the Guidelines

A bubble study can be performed to detect a patent foramen ovale (PFO) in a pregnant woman, but it should be done with caution and only when clinically necessary. The procedure involves injecting agitated saline solution into a peripheral vein while performing an echocardiogram to observe if bubbles cross from the right to left atrium, indicating a PFO. For pregnant women, transthoracic echocardiography (TTE) is preferred over transesophageal echocardiography (TEE) as it avoids sedation and is non-invasive. The radiation exposure from a bubble study is minimal, making it relatively safe during pregnancy. However, the test should only be performed if the results would significantly impact maternal management during pregnancy, such as in cases of cryptogenic stroke or severe migraines with aura. The timing of the study should ideally be during the second trimester when organogenesis is complete. The physiological changes of pregnancy, including increased blood volume and cardiac output, may actually make a PFO more detectable. If a PFO is identified, management typically remains conservative during pregnancy, focusing on monitoring rather than closure procedures, which are usually deferred until after delivery.

Some key points to consider:

• The decision to perform a bubble study should be based on the potential impact on maternal management during pregnancy 1.
• Transthoracic echocardiography (TTE) is the preferred method for pregnant women due to its non-invasive nature and minimal radiation exposure.
• The test should only be performed when clinically necessary, such as in cases of cryptogenic stroke or severe migraines with aura.
• The physiological changes of pregnancy may make a PFO more detectable, but management typically remains conservative during pregnancy.

It's essential to weigh the benefits and risks of the procedure and consider the potential impact on maternal and fetal health. The bubble study should only be performed if the results would significantly impact maternal management during pregnancy. In general, the management of PFO in pregnant women focuses on monitoring rather than closure procedures, which are usually deferred until after delivery 1.

From the Research

Bubble Study for Detecting PFO in Pregnant Women

• The use of bubble studies, specifically agitated saline bubble studies in conjunction with echocardiography, is a common method for detecting patent foramen ovale (PFO) 2.
• Transesophageal echocardiogram (TEE) bubble study is considered the gold standard for diagnosing PFO, with a weighted sensitivity of 89.2% and specificity of 91.4% 3.
• However, there is no direct evidence in the provided studies that specifically addresses the use of bubble studies in pregnant women to detect PFO.
• The studies focus on the general population and the accuracy of TEE bubble studies in detecting PFO, without mentioning pregnancy as a factor 3, 4, 5, 6.
• It is essential to consider the safety and potential complications of the procedure, as well as the potential benefits of detecting PFO in pregnant women, before making a decision about using bubble studies in this population.

Safety and Complications

• The studies mention that the bubble study is generally safe, with a low complication rate, such as 0.1% risk of transient ischemic attack (TIA) 4.
• However, the safety of the procedure in pregnant women is not specifically addressed in the provided studies.

Diagnostic Accuracy

• The diagnostic accuracy of TEE bubble studies in detecting PFO is well-established, with high sensitivity and specificity 3, 5.
• However, the studies also highlight the potential for false-positive and false-negative results, and the importance of understanding the limitations of the technique 2, 6.