An introductory guide to transesophageal echocardiogram (TEE)

Transesophageal echocardiography: definition

 

A good transesophageal echocardiogram definition would be to say that TEE is a type of echo diagnostic test that utilizes ultrasound waves to produce high-quality moving images of the heart and blood vessels.

 

This is achieved through a probe placed in the esophagus. The esophagus, with its close location to the upper chambers of the heart, provides an advantageous position for the production of accurate and clear images.¹

 

So, in cases where you need further detail than is provided by standard echocardiograms, transesophageal echocardiography is an essential ultrasound modality providing “additional and more accurate information than transthoracic echocardiography [TTE].”¹ TEE ultrasound has proved its utility in operating rooms, intensive care, and interventional labs as well as in outpatient settings.¹

3D live transesophageal echocardiogram: the basics

 

TEE ultrasound is used primarily to produce 2D images.³ However, advances in TEE technology have led to the development of live 3D TEE, such as found in Philips EPIQ CVx and X8-2t probe.

 

Real-time 3D TEE offers cardiologists, interventional cardiologists, echocardiographers and anesthesiologists greater visibility of cardiac structures and functions live in more detail than standard 2D TEEs can provide. The fact that you can see the complete valve, for example, enables monitoring during all stages of surgery. In other words, the imaging allows you to clearly assess repairs as well as results.⁴

 

There are many areas where the tool is extremely helpful. Three-dimensional transesophageal echocardiogram procedures have usability in:

 

• Understanding complex congenital heart diseases.
• Facilitating acquisition of right ventricle images.
• Providing optimal online volume-rendered 3D images of mitral valve.⁵
• Facilitating assessment of aortic valve.
• Guiding in minimally invasive surgery procedures.

 

In addition to Live 3D technology, portability has also made the use of TEE in emergency settings even easier, and it’s now a common feature in CCU and at bedsides.

What is a transesophageal echocardiogram used for?

 

TEE ultrasound is increasingly being used as an assistance tool not only by clinical cardiologists but also by cardiac interventionalists, anesthesiologists and cardiac surgeons. 

 

Among the most common TEE procedures and clinical applications are:

 

• Patients whose TTE is non diagnostic

- Patient with body habitus that makes it difficult to get images

- Patient on ventilator

- Patients with chest wall injuries.

• For diagnostic assessment

- Assessment of valvular disease

- Assessment of cardiac function

- Assessing prosthetic heart valves.

• For interventional procedure guidance

- Visualization of soft tissue to assist with device guidance, placement and post deployment.

• Intraoperative for surgery

- All open-heart surgeries, e.g. valve replacement

- Assessing a patients’ status before surgery

- Sometimes for coronary artery bypass surgeries.

• Cardioversion

- Assessment of risk (presence of thrombus).

 

It is extremely important to note that TEE ultrasound cannot be recommended in cases of:

• Perforated viscus
• Esophageal stricture
• Esophageal tumor
• Esophageal perforation
• Esophageal diverticulum
• Active upper GI bleeding.¹

Transesophageal echocardiogram: TEE training

 

As 90% of TEE assessments are performed by cardiac anesthetists2 rather than cardiologists, proper TEE ultrasound training is required for this modality of assessment to be effective and safe.

 

ASE, in its guidelines and standards for performing TEE examination safely and effectively, has listed the below as essential cognitive and technical requirements for competence in adult TEE:¹
 

• Basic knowledge of TTE and echocardiography.
• Knowledge of TEE indications and contraindications.
• Knowledge of infection control measures.
• Knowledge of cardiovascular anatomy as well as alterations to it.
• Knowledge of congenital heart diseases and their appearance on TEE.
• Proficiency in safe and effective sedation.
• Proficiency in performing TEE examination.
• Proficiency in passing TEE probe through the esophagus and stomach, adjusting as needed.
• Proficiency in analyzing the data produced.

 

Specialized knowledge of operating relevant ultrasound equipment and probe handling is also extremely important. That’s why Philips provides an introductory course on the use of Live 3D TEE, designed for anesthesiologists, cardiologists and sonographers undertaking Live 3D TEE studies.

 

With proper compliance with training and industry-standard procedure guidelines, the use of TEE can continue to improve diagnostic confidence and have a positive impact on cardiovascular patient care.