Can a bubble study be done with a Transesophageal Echocardiogram (TEE)?

Can a Bubble Study Be Done with TEE?

Yes, bubble studies can be performed during both transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE), with TEE actually providing superior sensitivity for detecting cardiac shunts compared to TTE. 1, 2

TEE Offers Superior Sensitivity for Shunt Detection

• TEE demonstrates significantly higher sensitivity (51%) compared to TTE (32%) for detecting cardiac shunts, making it the preferred modality when high diagnostic accuracy is required 1, 2
• The American College of Cardiology considers bubble studies during TEE essential for detecting right-to-left shunts and this is a standard requirement for echocardiography training 2
• TEE provides unobstructed views of posterior cardiac structures and higher spatial resolution than TTE, which enhances visualization of atrial septal defects and shunt pathways 3

Clinical Applications of TEE Bubble Studies

• TEE with agitated saline is particularly valuable for evaluating cryptogenic stroke patients where patent foramen ovale (PFO) may be the cause of paradoxical embolism 1
• The American College of Radiology recommends TEE bubble studies to verify the presence of shunts in known or suspected congenital heart disease 1
• TEE bubble studies help differentiate between intracardiac and extracardiac shunts, providing critical diagnostic information that TTE may miss 4, 1
• TEE can provide new or altered diagnoses (14%) or new information (56%) in adults with congenital heart disease, including improved assessment of atrial septum, systemic and pulmonary venous connections, and atrial baffle function 4

Technical Considerations and Procedure

• The procedure involves injecting agitated saline containing microbubbles intravenously while performing TEE to identify shunts 1
• TEE requires topical anesthetic spray to the oropharynx and intravenous conscious sedation for patient comfort 3
• The examination may be unsuccessful in 3-5% of patients due to inability to tolerate the probe, and another 4-5% require general anesthesia 4

Important Caveats

• TEE has specific blind spots: it provides limited visualization of the right ventricular outflow tract, pulmonary valve, distal right pulmonary artery, and proximal left pulmonary artery 4
• The apical-anterior septum and areas masked by prosthetic material may also be poorly visualized 4
• TEE is operator-dependent and requires specialized training in interpreting complex congenital heart disease findings in real-time 4
• Complications are rare but include pharyngeal and esophageal trauma, adverse reactions to sedation, and rarely methemoglobinemia from benzocaine administration 3

When to Choose TEE Over TTE for Bubble Studies

• Use TEE when TTE provides inadequate or non-diagnostic images, particularly in adults with poor acoustic windows due to obesity, narrow intercostal spaces, or severe pulmonary emphysema 3
• TEE is preferred when evaluating the atrial septum for PFO closure planning, as it provides accurate assessment of secundum atrial septal defect size and rim length comparable to CT 4
• Consider TEE for intraoperative monitoring during cardiac surgery or guidance during catheter-based interventions and device placement 3