Noninvasive estimation of right ventricular filling pressure by ratio of early tricuspid inflow to annular diastolic velocity in patients with and without recent cardiac surgery.

BACKGROUND: Few data are available on the evaluation of right ventricular (RV) diastolic function and filling pressures by echocardiography. We aimed to determine whether the ratio of early tricuspid inflow to annular diastolic velocity (E/E') could be used to estimate RV filling pressure in patients with and without recent cardiac surgery.
METHODS: In all, 101 data sets including invasive and echocardiographic measurements (42 after recent cardiac surgery) were simultaneously obtained from patients in the intensive care department. Tissue Doppler measurements were performed from the tricuspid annulus. E/E' was related to catheter right atrial pressure (RAP) measurements.
RESULTS: E/E' correlated only moderately with RAP early after cardiac surgery (r = .41, P = .007), whereas E/E' correlated strongly with RAP in patients without cardiac surgery (r = .83, P < .0001). The sensitivity and specificity of E/E' 4 or greater were 88% and 85% for RAP 10 mm Hg or greater in patients who were not in the postcardiac surgery status (receiver operating characteristic area 0.93 [95% confidence interval: 0.86-0.99]) but 44% and 73% early after cardiac surgery (receiver operating characteristic area 0.56 [95% confidence interval: 0.37-0.75]). E/E' correlated more strongly with RAP when the RV systolic function was impaired. In repeated measurements from 12 patients, an increase of greater than 2 in E/E' was associated with an increase of 5 mm Hg or more in the RAP with a sensitivity of 67% and a specificity of 89%.
CONCLUSIONS: E/E' is useful for noninvasive estimation of RV filling pressure and to detect serial changes in a wide range of clinical conditions but is a weak correlate of RAP early after cardiac surgery and in patients with normal RV function.