Objective: To derive a clinically useful, noninvasive determination of right atrial pressure. Noninvasive assessment of right ventricular systolic pressure from Doppler-derived tricuspid regurgitant velocity requires an accurate assumption of right atrial pressure.
Patients and methods: Seventy-one patients were studied in the cardiac catheterization laboratory, comparing right atrial pressure (measured at mid systole) with simultaneous 2-dimensional echocardiographic measurement of inferior vena cava diameter and Doppler recordings of hepatic vein systolic, diastolic, and atrial reversal velocities. The initial 28 patients were used to derive a clinical algorithm to predict right atrial pressure, which was tested in the subsequent 43 patients.
Results: Inferior vena cava dimension correlated directly with right atrial pressure (r2=0.74; P<.001). The systolic filling fraction of the hepatic vein velocity curves correlated poorly with right atrial pressure. However, the correlation between the hepatic vein Doppler sum of systolic forward flow velocity and atrial reversal velocity and right atrial pressure was inverse (r2=0.32; P=.002). With a combination of variables from both inferior vena cava diameter and hepatic vein velocity curves, patients can be divided into those with normal right atrial pressure, mildly increased right atrial pressure, and severely increased right atrial pressure.
Conclusion: The combined information from inferior vena cava diameter and hepatic vein velocity curves can be used to assess right atrial pressure.