What does transesophageal echocardiography (TEE) provide that transthoracic echocardiography (TTE) may not?

Transesophageal echocardiography (TEE) offers superior visualization of posterior cardiac structures compared to transthoracic echocardiography (TTE) primarily due to the proximity of the echocardiographic transducer to the heart when the transducer is placed in the esophagus. This close proximity allows TEE to obtain images with less interference from lung and chest wall tissues, which can obscure structures in TTE. Specifically, TEE excels at visualizing areas such as the left atrium, mitral valve, and certain aspects of the aorta, which are critical in assessing conditions such as atrial septal defects or valvular heart diseases.

In contrast, TTE may struggle to provide clear images of these posterior structures due to the higher distance and additional intervening anatomical structures, which can attenuate the ultrasound signals. This advantage makes TEE a valuable tool for more detailed assessments in various clinical scenarios, especially when more definitive imaging is required to guide diagnosis and treatment.