[Thermodilution vs transesophageal echocardiography for cardiac output measurement in patients with good left...

Area of Science:

• Cardiovascular Medicine
• Diagnostic Imaging
• Echocardiography

Background:

• Transesophageal echocardiography (TEE) is a standard diagnostic tool for assessing cardiac output in various cardiac conditions.
• TEE enables real-time estimation of ejection fractions, stroke volumes, and cardiac output, crucial for surgical repair assessment.
• This study investigates novel TEE Doppler methods for cardiac output measurement.

Purpose of the Study:

• To compare cardiac output estimations using aortic continuous-wave Doppler and pulse-wave Doppler via TEE.
• To validate these TEE-derived cardiac output measurements against the established thermodilution method.

Main Methods:

• Cardiac output was measured in 30 adult patients undergoing off-pump coronary artery bypass grafting.
• Aortic valve area was calculated from the transverse short-axis view, assuming a triangular orifice shape.
• Measurements included thermodilution (CO(S-G)), contour wave analysis (CO(CW)), and continuous-wave Doppler (CO(PW)) via TEE.

Main Results:

• Mean cardiac output values were comparable across all three methods: thermodilution (4.59 L/min), CO(CW) (4.49 L/min), and CO(PW) (4.57 L/min).
• A strong positive correlation was observed between thermodilution and CO(CW) (r=0.939, p<0.001).
• A strong positive correlation was also found between thermodilution and CO(PW) (r=0.912, p<0.001).

Conclusions:

• Cardiac output measurements obtained via transesophageal echocardiography using continuous-wave and pulse-wave Doppler are comparable to thermodilution.
• These findings support the use of TEE Doppler techniques as a reliable method for assessing cardiac output in clinical practice.