Transesophageal echocardiography provides an excellent window for examining the heart and great vessels. Its clinical applications include, but are not limited to:
- detection and assessment of endocarditis and its complications
- aortic dissection and other aortic pathologies
- intracardiac thrombi and other masses
- evaluation of valvular disorders including prosthetic valve function
- evaluation of a variety of CHD in both children and adults
Since transesophageal echocardiography is a minimally invasive procedure with small but definite risks, its use should be reserved for clinical circumstances in which the potential findings have significant implications for patient management and cannot be obtained by transthoracic evaluation.
TEE Training Experience
Fellows gain proficiency in performing transesophageal studies on a regular basis. All procedures will be done under the direct supervision of a cardiology echo attending.
At a minimum, a fellow must reach Level II training in transthoracic echo and complete at least 50 supervised transesophageal studies in order to be certified as having the required skills to perform this study independently.
There are opportunities to do intraoperative transesophageal echocardiograms in the operating room supervised by the cardiology echo attending.
Patient selection, conscious sedation techniques, instrumentation, performance and interpretation of TEEs are taught. Fellows are required to interface with all patients and obtain a detailed history and perform a physical exam prior to performing TEEs. All procedures are performed under the direct supervision of a cardiology echo attending who is certified in providing conscious sedation. Finally, though an assigned echo technologist is available to clean the TEE probes, it is expected that all fellows will learn to clean the TEE probes with both enzymatic and Cidex sterilization. Pregnancy will exempt any handling of TEE probes for cleaning.
TEE Procedure
Transesophageal echocardiography requires the insertion of an endoscopic probe into the esophagus and manipulating the probe through multiple imaging planes to obtain tomographic views of the heart and great vessels. To reduce the level of discomfort associated with the procedure, a topical anesthetic spray is administered to the oropharynx, and intravenous conscious sedation is often used. Consequently, the physician performing a TEE must be knowledgeable with regard to:
- pharyngeal and esophageal anatomy
- the proper use of conscious sedation, including the prompt recognition of possible complications
- the various techniques of esophageal intubation and probe manipulation
- the recognition and management of possible complications of probe insertion, including the infrequent occurrence of methemoglobinemia as a complication of benzocaine administration
- the absolute and relative contraindications to the performance of a TEE examination
The operator must also have the necessary technical knowledge required to operate the ultrasound machine. Importantly, the physician performing a TEE needs good communication skills in order to explain the TEE procedure to patients in simple terms, including its risks, benefits, and alternative approaches—and in order to obtain the patient's cooperation during the examination. In many patients, the results of a TEE examination guide urgent and definitive treatment (such as emergency surgery in a patient with an ascending aortic dissection); thus, the physician performing a TEE needs to have thorough knowledge of cardiovascular disorders and their accompanying hemodynamic alterations, the different diagnostic issues that require consideration given a particular clinical presentation, and the potential therapies available. The operator also needs to have mastered a thorough understanding of the basic principles of ultrasound imaging and Doppler hemodynamic assessment described in detail in the previous sections.
Although it is usually preferable to perform a comprehensive and systematic TEE examination, it is not always possible, particularly in critically ill patients. Consequently, it is essential that the operator evaluate the most pressing diagnostic issues first. Therefore, the physician performing a TEE must be able to review available clinical and diagnostic information, including data from the TTE, in order to prioritize the most relevant issues and focus the TEE examination on resolving these issues.
Training in TEE must include:
- attainment of at least Level 2 experience in general TTE
- performance of approximately 25 esophageal intubations with a TEE probe
- performance of approximately 50 diagnostic TEE examinations under the supervision of an experienced (Level 3) echocardiographer, including the review, interpretation, and reporting of study findings.
It is important to emphasize that in certain specialized clinical circumstances, even this training may not be sufficient for the independent performance of a TEE.
TEE Certification
Fellows who wish to acquire sufficient experience in TEE to allow certification as an independent operator are encouraged to spend an additional 3 months of dedicated training in echocardiography. During this time, they receive didactic instruction in the indications for TEE, technical aspects of handling the transducer and technique of esophageal intubation, image acquisition, and study interpretation. Procedural responsibility is gradually increased as deemed appropriate.
The program requires 75 documented and supervised studies for certification as an independent operator. Only 1 trainee can claim credit for a particular transesophageal echocardiographic study.
Proof of Competence
Documentation of competence can be achieved by means of a letter or certificate from the fellowship program director after confirmation from the echo lab director that the trainee obtained the required TEE training for such certification. This documentation should state that the trainee successfully achieved or surpassed each of the training elements, and the dates of training.
At Montefiore Medical Center we strongly recommend to our fellows to take the board examination offered by the NBE, and achieve certification in the relevant practice areas of echocardiography (i.e., general transthoracic, TEE, stress echocardiography, or comprehensive certification).
Table 2: COCATS Training Requirements for Transesophageal Echocardiography
Component |
Objective
|
Caseload
|
Level II TTE
|
Background knowledge and skills
|
150 TTE
|
Esophageal Intubation
|
TEE probe introduction
|
25
|
TEE Exams
|
Performance and interpretation
|
50
|