Trans-esophageal Echocardiography Imaging

Presenter: John Shiels, Nurse Anesthetist specializing in cardiac anesthesia

Objectives

• Describe the use of perioperative TEE (PTE) as an advanced cardiac monitor.
• Utilize 11 relevant windows for hemodynamic monitoring.
• Discuss advanced PTE with applications like Doppler, aortic valve gradients, and perivalvular leaks.

Basics of Ultrasound Physics

• Probe emits sound waves through tissue, converting electrical energy to sound.
• Returning sound waves generate an image.
• Best images are created when the beam is perpendicular to the structure.
• Probe manipulation akin to fiber optic bronchoscope.
• Used in different positions: upper esophageal, mid-esophageal, trans-gastric, deep trans-gastric.

TEE Imaging Views

• Mid-esophageal views: Left atrium often in near field.
• Upper esophageal: Near aortic arch.
• Deep trans-gastric: For Doppler measurements.

Applications and Information from Basic TEE

• Assess ventricular function and chamber size.
• Monitor ischemia, vessel integrity, valve function.
• Detect heart tumors, pericardial effusion.

Advanced TEE Applications

• Diagnosis of specific pathologies using more views.
• Use of Doppler for valve assessment and intervention.
• Requires knowledge of 3D imaging.

Contraindications and Risks

• Mortality <1%, morbidity between 2 to 5 in 10,000.
• Risks include esophageal perforation, GI bleed, dental damage.
• Considerations for probe insertion and equipment protection.

Detailed TEE Views

• Mid-esophageal four chamber: High utility, assesses chamber size, ventricular function.
• Mid-esophageal two chamber: Views of left atrium and ventricle.
• Mid-esophageal long axis: Aortic valve and LVOT assessment.
• Bicaval view: Used for atrial septal defects, central line placement.
• Transgastric short axis: Assesses ventricular size and function, wall motion.

Doppler and Advanced Imaging Techniques

• Doppler: Assesses flow direction and velocity, important for valve assessment.
• Continuous wave Doppler: Measures aortic valve gradient.

Comprehensive TEE

• Combines multiple views for detailed diagnostic information.
• Includes assessment of surgical interventions, advanced Doppler.

Perioperative Use of Echocardiography

• TEE and TTE utility throughout the perioperative period.
• TTE offers less invasive options but may not provide detailed images needed for certain procedures.

Conclusion

• Basic TEE uses 11 windows for effective assessment of cardiopulmonary instability.
• Advanced TEE provides detailed diagnostics using up to 28 windows.
• TTE extends echo use through the perioperative period, offering different advantages.