Accuracy of Tissue Doppler Estimation of the Right Atrial Pressure in Anesthetized, Paralyzed, and Mechanically Ventilated Patients

The ratio of tricuspid peak early inflow velocity to peak early diastolic velocity of the lateral tricuspid annulus (the E/Ea ratio) measured by transthoracic echocardiography has been reported to correlate with right atrial (RA) pressure. In this study, the correlation between the E/Ea ratio and RA pressure was tested in 44 anesthetized, paralyzed, and mechanically ventilated patients by transesophageal echocardiography. Mean RA pressure and the following echocardiographic data were recorded simultaneously: tricuspid peak early inflow velocities by Doppler echocardiography, peak early diastolic velocity of the lateral tricuspid annulus by tissue Doppler imaging, and right ventricular and left ventricular end-diastolic areas. Linear regression did not indicate a correlation between the E/Ea ratio and RA pressure (r = −0.11, p = 0.48) or between the E/Ea ratio and the right or left ventricular end-diastolic area index; it revealed a weak correlation between RA pressure and the inspiratory plateau pressure and body mass index. In conclusion, the E/Ea ratio failed to predict RA pressure or planimetric indexes of ventricular preload in anesthetized, paralyzed, and mechanically ventilated patients. In these patients, RA pressure was largely influenced by extracardiac factors.