Basic Physics of Transesophageal Echocardiography

Consensus on Perioperative Transesophageal Echocardiography of the Brazilian Society of Anesthesiology and the Department of Cardiovascular Image of the Brazilian Society of Cardiology

“… 24 The perpendicular contact of the US beams with these near field allows us to use the highest available frequencies, with consequent detailed appreciation of their morphology. 5 The use of zoom as a resource to increase the detail for distance and/or diameters measurements can further improve accuracy and is recommended ( Fig. 20 ).…”

“…The Doppler bundles perpendicularity with these structures in the mid-esophagus echocardiographic sections makes it impossible to accurately assess the flow velocities. 5 This limitation is overcome with TG long axis ( Fig. 8 B) and deep TG sections ( Fig.…”

“…7 D), in which the parallel alignment with the beams allows an accurate assessement. 5 , 27

Figure 20 Mid-esophageal aortic valve long axis cross-section. LVOT, left ventricular outflow tract; IVS, interventricular septum; RC, right coronary; Asc Ao, ascending aorta.

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“…Transesophageal echo transducer should be positioned in mid-esophageal four-chamber and RV centralized. 3 , 5 , 6 In a minority of patients, a modified incidence of RV deep transgastric can be obtained by rotating the probe to the right (as in the figure), which allows US good alignment with tricuspid ring motion. Velocity indexes: isovolemic acceleration ( Fig.…”

“…In addition, the TEE transducer may be attached to a specific part of the esophagus or stomach, which allows a more detailed analysis of the cardiac anatomy. 1 , 5 The current TEE transducers operate at a frequency of 3.5–7 MHz, reaching up to 20 MHz. 5

Figure 1 Anatomical relationships for transesophageal probe, esophagus, and heart.

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