Determination of cardiac output by Doppler echocardiography

Area of Science:

• Cardiology
• Medical Imaging
• Hemodynamics

Background:

• Assessing cardiac output is crucial for managing patients with angina pectoris.
• Invasive methods for cardiac output measurement can be burdensome.
• Non-invasive techniques like Doppler echocardiography offer a promising alternative.

Purpose of the Study:

• To compare cardiac output measurements between Doppler echocardiography and invasive methods (thermodilution and Fick) in patients with angina pectoris.
• To determine the optimal parameters for accurate non-invasive cardiac output assessment using Doppler echocardiography.

Main Methods:

• Cardiac output was measured using Doppler echocardiography and compared with thermodilution (at rest and during dobutamine infusion) and the Fick method (at rest).
• Patients with angina pectoris but no valvular heart disease were included.
• Doppler-derived maximum spatial blood velocity and cross-sectional aortic area were used to calculate cardiac output.

Main Results:

• The best correlation between Doppler echocardiography and invasive methods was achieved when using maximum velocity in the aortic root and the aortic orifice area.
• Cardiac output calculations were significantly overestimated when area measurements from the aortic root were utilized.
• Doppler echocardiography demonstrated good correlation with invasive methods under specific parameter choices.

Conclusions:

• Doppler echocardiography can reliably estimate cardiac output in angina patients.
• Accurate non-invasive cardiac output assessment requires precise selection of measurement sites, specifically aortic root velocity and aortic orifice area.
• Avoid using aortic root area measurements to prevent overestimation of cardiac output.