RELATION OF MEAN RIGHT ATRIAL PRESSURE TO ECHOCARDIOGRAPHIC AND DOPPLER PARAMETERS OF RIGHT ATRIAL AND RIGHT-VENTRICULAR FUNCTION

Background A paucity of data exists as to the relation of mean right a trial pressure (RAP) to Doppler parameters of right atrial and ventric ular filing. Furthermore, whether echocardiographic parameters of righ t atrial and right ventricular function and inferior vena cava improve the relation of Doppler filling dynamics with RAP has not been explor ed. Methods and Results Doppler and echocardiographic studies were per formed simultaneously with measurements of mean RAP in consecutive pat ients who either had a central venous catheter in the Intensive Care U nit or underwent catheterization of the right side of the heart. The i nitial population consisted of 35 patients with a mean age (+/-SD) of 60+/-15 years; 34% were on mechanical ventilation. Mean RAP averaged 9 +/-5.7 mm Hg (range, 2 to 28 mm Hg). Among tricuspid inflow parameters , the strongest relation with RAP was observed with the ratio of early to late velocity (r=.66). For hepatic venous flow, systolic filling w ave indexes had the best relation with atrial pressure, the highest be ing for systolic filling fraction (r=-.86). Weaker relations were note d with the use of right atrial volumes, right ventricular function, an d inferior vena caval diameters. The addition of any of these variable s did not improve the relation of systolic filling fraction with RAP. The regression equation (RAP=21.6-24 systolic filling fraction) was te sted prospectively in the estimation of atrial pressure in 50 patients . The correlation coefficient was .89 in the prospective group and .88 in the total group of 85 patients. The mean difference between predic ted and actual pressures in the whole population was -0.2+/-2.6 mm Hg. The sensitivity and specificity for mean RAP>8 mm Hg were 86% and 92% , respectively. Conclusions Among echocardiographic and Doppler parame ters of right atrial and right ventricular function, hepatic venous fl ow dynamics relate best to mean atrial pressure and can be used clinic ally to estimate mean RAP.