An echocardiogram uses ultrasound to create pictures of your heart, allowing doctors to assess its structure and function.
There are two main types: a transthoracic echocardiogram (TTE), which is non-invasive and uses a probe on your chest, and a transesophageal echocardiogram (TEE), which is semi-invasive and involves a probe going down your esophagus.
What are the key differences, and when would a doctor choose one over the other?
Imaging windows and visualization
Transthoracic echocardiography (TTE)
With TTE, the sonographer has four main “windows” to view the heart: parasternal (alongside the sternum), apical (at the heart’s apex), subcostal (below the ribs), and suprasternal (above the sternum).
The challenge with TTE is that image quality can be affected by a person’s body type, lung disease, or chest wall irregularities.
Transesophageal echocardiography (TEE)
TEE provides much clearer images because the probe is closer to the heart. This is especially true for the left atrium (LA), left atrial appendage, aortic plaques, and mitral valve.
Clinical Applications and Diagnostic Yield
Both TTE and TEE are valuable tools, but they shine in different clinical situations.
Transthoracic Echocardiography (TTE)
TTE is often the first step in evaluating heart problems. It’s used to assess cardiac function, check for valve disease, and look for pericardial effusion (fluid around the heart). TTE is also good at detecting general heart abnormalities, like assessing how well the left ventricle is pumping (LVEF).
Transesophageal Echocardiography (TEE)
TEE is preferred in situations where a clearer, more detailed view is needed. This includes looking for potential heart-related causes of blood clots (emboli), assessing aortic dissection (a tear in the aorta), diagnosing endocarditis (infection of the heart valves), and evaluating prosthetic valve problems. TEE is particularly good at detecting aortic plaques and blood clots in the left atrial appendage, where clots often form in people with atrial fibrillation.
One study found a cardiac source of emboli in 16% of all patients undergoing TEE, and in 18% of patients over 45 years old.
Risks, Contraindications, and Limitations
Transthoracic Echocardiography (TTE)
TTE is noninvasive and well-tolerated, so it has very few risks associated with it.
Transesophageal Echocardiography (TEE)
TEE carries a few more risks, including esophageal perforation, bleeding, and aspiration. If you have esophageal strictures, tumors, or have had recent esophageal surgery, you may not be a good candidate for TEE.
If you undergo a TEE, you will have to avoid eating or drinking beforehand, and you’ll likely be given a sedative to help you relax.
Frequently Asked Questions
Why is TEE preferred over TTE in some cases?
TEE provides clearer and more detailed images of the heart than TTE because the probe is closer to the heart and doesn’t have to go through the ribs or lungs. This makes it especially useful for visualizing structures like the heart valves and aorta, and for detecting blood clots or infections.
What is the difference between an echocardiogram and a transthoracic echocardiogram?
The terms are often used interchangeably. A transthoracic echocardiogram (TTE) is the most common type of echocardiogram. It’s a non-invasive procedure where a transducer is placed on the chest to create images of the heart. So, TTE is simply one specific type of echocardiogram.
What is the difference between a TEE and TTE?
The main difference lies in how the images are obtained. TTE is non-invasive and uses a transducer on the chest. TEE involves inserting a probe with a transducer down the esophagus, providing a closer and clearer view of the heart from behind.
When do you use transthoracic vs transesophageal echo?
TTE is typically the first-line test for evaluating heart structure and function. TEE is used when TTE images are not clear enough, or when a more detailed view of specific heart structures is needed, such as for evaluating heart valves, blood clots, or infections inside the heart.
In Summary
TTE and TEE both create pictures of your heart, but they work differently. TTE is a simple, non-invasive test, while TEE provides a more detailed picture of the heart.
Your doctor will choose the best test for you based on your condition. TEE often spots heart problems that TTE misses, especially in older adults.