Introduction to Transesophageal EchocardiographyNakeisha L. Pierre, M.D

Tulane Department Anesthesiology

Look Familiar?!

IVC or SVC ?

Basic Principles of Ultrasound and Doppler

Echocardiography creates images of the heart from reflected sound waves

The ultrasound transducer records the time delay and amplitude for each returning transmission

Speed in a medium is constant, so only the distance of the structure from the probe alters the time to receive the reflected wave

Timing the interval between transmissions and the time it takes to receive reflected signals allows the ultrasound system to precisely calculate the location of structures and construct images

Basic Principles of Ultrasound and Doppler

2-D echo is unable to visualize blood flow.. It’s presented as just black on the display

Doppler ultrasonography overcomes this limitation The Doppler system determines the velocity of blood

flow by assessing the change in frequency of the ultrasound reflected from moving red blood cells

Directing the ultrasound at the flow of blood and listening for those changes in frequency allows Doppler echo to determine direction and speed of blood flow

Basic Principles of Ultrasound and Doppler

Frequency (cycles/s) is a property exclusive to the echo transducer/probe ( 2-10Hz)

Frequency determines signal strength and imaging resolution Signal strength

Lower freq – stronger signal Disadvantage is decreased image

resolution Imaging resolution

Higher freq – better image resolution

Disadvantage – decreased penetration/weaker signal

Doppler Flow

Category I Indications for Intra-Operative TEE

Acute, persistent life-threatening disturbances Valve repair – particularly mitral valve Aortic valve resuspension in dissection or aneurysm sx Congenital heart surgery Obstructive cardiomyopathy Endocarditis Thoracic Aortic Aneurysm Pericardial Window

*conditions for which there is evidence and/or general agreement that a given procedure is useful and effective*

Category II Indications for Intra-Operative TEE

Increased risk for MI or unstable hemodynamics Valve replacement Myocardial aneurysm repair Cardiac assist devices Myocardial/intracardiac mass rsxn Foreign body detection or removal Pulmonary endareterctomy Suspected cardiac trauma Aortic atheromatous disease Pericardial surgery Cardiac or pulmonary transplantation

*Conditions for which there is conflicting evidence and/or divergence of opinion about the usefulness or efficacy of procedure/treatment*

Contraindications to Intra-Operative TEE Esophageal disease – stricture, diverticuli, varices,

tumor Prior esophageal or stomach surgery Perforated viscus Difficulty passing the TEE probe Anticoagulation Thrombocytopenia Facial or airway trauma

Anatomical Relationships The esophagus provides an excellent window for visualizing detailed

echocardiographic images secondary to its close proximity to the heart The esophagus extends from the posterior pharynx through the

mediastinum where it courses behind the trachea left main bronchus and continues inferiorly where it becomes immediately adjacent to LA and LV

Esophagus

Comprehensive TEE Exam 20 views recommended by ASE task force Goal during any exam is to visualize structure

and function of heart and not necessarily get all 20 views

Comprehensive TEE Exam

Comprehensive TEE Exam Views designated by

Echo window Upper esophageal (20-25cm) Mid esophageal (30-40cm) Transgastric (40-45cm) Deep transgastric (45-50cm)

Main anatomic structure AV RV

Imaging plane Short axis/SAX Long axis/LAX

Comprehensive TEE Exam At a multiplane angle of 0 degrees

(the horizontal or transverse plane), with the imaging plane directed anteriorly from the esophagus through the heart, the patient’s right side appears in the left of the display.

Rotating the multiplane angle forward to 90 degrees (vertical or sagittal plane) moves the left side of the display inferiorly, toward the supine patient’s feet.

Rotating the multiplane angle to 180 degrees places the patient’s left side to left of the display, the mirror image of 0 degrees.

Orientation of the Heart

Comprehensive TEE Exam

Advance

Withdraw

Flex to Left

Anteflex

Retroflex

Flex to Right

Mid.Ant line rotation

ME Asc Aortic SAXAngle: 10-30 degrees

Diagnostic Uses: aortic atherosclerosis, aortic dissection/ dilation, PA pathology (emboli)

ME Asc Aortic LAXAngle: 100 degrees

Diagnostic Uses: aortic atherosclerosis, aortic dissection, asc aortic dilation

Ascending Aorta

Right Pulmonary A.

ME AV SAXAngle:25-45 degrees

Diagnostic Uses: aortic stenosis, valve morphology

NCC

LCC

RCC

ME RV Inflow-OutflowAngle: 50-70 degrees

Diagnostic Uses: PV disease, PA pathology, RVOT pathology

ME BicavalAngle: 105-120 degrees +/- rightward rotation

Diagnostic Uses: right atrial free wall, SVC, interatrial septum, IVC

Positive Bubble Study

ME AV LAXAngle: 115-130degrees

Diagnostic Uses: AV pathology, aorta pathology, LVOT pathology

ME four chamber Angle:0-10 degrees

Diagnostic Uses: ASD, chamber enlargement/dysfxn, LV regional wall motion abnml,mitral dz, tricsupid dz, intracardiac

Lateral Wall

Septal Wall

Mitral Valve

ME Mitral CommissuralAngle: 60-75 degrees

Diagnostic Uses: localization of mitral valve pathology

P1A2

P3

ME two chamberAngle:80-100degrees

Diagnostic Uses: left atrial appendage mass/thrombus,LV apex pathologyLV systolic fxn/RWM

A3A2A1

P3

Coronary Sinus

ME LAXAngle: 110-130 degrees

Diagnostic Uses: MV pathology, LVOT pathology, LV RWM abnml

A2P2

Anteroseptal Wall

Posterior Wall

TG Basal SAXAngle: 0 degrees +/- anteflexion

Diagnostic Uses: LV systolic dysfunction, MV pathology

Posterior Leaflet

Anterior Leaflet

TG Mid(pap) SAXAngle:0 degrees w/ anteflexion

Diagnostic Uses: hemodynamic instability, LV dilation/hypertrophy, LV systolic function, LV RWM

Transgastric Two ChamberAngle: 90 degrees

Diagnostic Uses: LV systolic dysfunction (ant/inf walls)

(ant)

Anterior Wall

Inferior WallInferior

Anterior

TG LAXAngle: 110-130 degrees +/- left rotation

Diagnostic Uses: LV systolic dysfunction, doppler AV

AV

TG RV InflowAngle: 110-130 degrees + right rotation

Diagnostic Uses: RV systolic fxn, tricuspid pathology

RARV

Tricuspid Valve

Deep TG LAXAngle: 0 degrees + anteflexion

Diagnostic Uses: AV pathology, LVOT pathology, doppler AV

Desc Aortic SAXAngle: 0 degrees

Diagnostic Uses: aortic atherosclerosis, aortic dissection

Desc Aortic LAXAngle: 90 degrees

Diagnostic Uses: aortic atherosclerosis, aortic dissection, IABP placement

UE Aortic Arch LAXAngle: 0 degrees + rightward rotation

Diagnostic Uses: aortic atherosclerosis/dissection, measure distal asc aorta

Aortic Arch

UE Aortic Arch SAXAngle: 90 degrees

Diagnostic Uses: aortic atherosclerosis/dissection

Aortic ArchPulmonary

Artery

Pulmonic Valve

References Fleisher, et al. Intraoperative TEE. Philadelphia: Elsevier, 2008 Perrino, et al. A Practical Approach to Transesophageal Echo.

Philadelphia: Lippincott, 2008 Peak. Nuts and Bolts of Ultrasound Physics. Houston, 2006 Riedel. Guidelines for Performing a Comprehensive Intraoperative

Multiplane TEE exam. Houston, 2006 Shanewise, et al. ASE/SCA Intraoperative TEE Guidelines. Anethes

Analg 1999:89:870-84 Sidebotham. Practical Perioperative TEE. London: Butterworth

Heinmann, 2003