Comparison of the Three Different Formulas for Doppler Estimation of Pulmonary Artery Systolic Pressure

Abstract

Noninvasive pulmonary artery systolic pressure (PASP) is calculated by summing the right ventricular systolic pressure obtained from Doppler velocity of regurgitant flow through the tricuspid valve and the right atrial (RA) pressure. The RA pressure is generally assumed from different formulas. An accurate RA pressure estimation will add precision to PASP calculation. One of the methods to estimate RA pressure is the inferior vena cava collapsibility index (IVCCI). In 45 patients referred for right heart catheterization, the authors tested a formula for the calculation of PASP based on the estimation of RA pressure from IVCCI and compared this method with two other formulas. The first method (method 1) assumed a constant RA pressure of 10 mm Hg irrespective of right ventricular pressure. The formula used was Doppler gradient + 10 (mm Hg). In the second method (method 2), a clinical estimate of RV pressure was made from the formula: right ventricular-right atrial Doppler gradient x 1.1 + 14. In the third method (method 3), the patients were classified into three groups on the basis of IVCCI: group A, IVCCI greater than 45%; group B, IVCCI between 35% and 45%; and group C, IVCCI less than 35%. The formula used was Doppler gradient + 6, 9, or 16 mm Hg in the presence of normal (group A), moderately reduced (group B), or markedly reduced (group 3) IVCCI. A good correlation between Doppler and catheter measurements of PASP was found for methods 1, 2, and 3, respectively (r=0.8933, SEE=6.4, r=0.8921, SEE=7.0, and r=0.8989, SEE=6.7). Correlation between invasive and noninvasive PASP was similar with the three methods, but correlation in method 2 was less satisfactory than with the other two methods. The mean difference between Doppler-derived and hemodynamic PASP was also high in method 2. In conclusion, the result of this study validates a relatively new, simple echo-Doppler formula for Doppler estimation of PASP based on a noninvasive evaluation of RA pressure through the IVCCI. However, this method is not better than the traditional method 1 for noninvasive PASP estimation.

Diagnostic accuracy of echocardiography for pulmonary hypertension: a systematic review and meta-analysis

“…The I 2 statistic was 99% (95% CI 88 to 99) indicating significant heterogeneity between the studies. Subgroup analysis for studies with a mean sPAP of 50 mm Hg or less revealed a summary correlation of 0.65 (95% CI 0.61 to 0.69; n=12)30 31 33 35 36 39 42 43 45–47 54 and for studies with a mean sPAP greater than 50 mm Hg, 0.71 (95% CI 0.65 to 0.77; n=8) 38 41 48–50 52 53 56. Egger's test revealed significant publication bias (p<0.001), which was consistent with an asymmetrical funnel plot with missing studies in the lower left and upper right (figure 4).…”

Geometric Determinants of Functional Tricuspid Regurgitation

“…14 -17 Right ventricular systolic pressure (RVSP) was estimated from the tricuspid regurgitant velocity with the modified Bernoulli equation: 4ϫ(velocity) 2 ϩ10 mm Hg for right atrial pressure. 18,19 The use of 10 mm Hg for estimation of right atrial pressure provides a consistent estimation of RVSP across a broad spectrum of patients referred for echocardiography and compares favorably with hemodynamic measurements. 18 -20 Right ventricular (RV) function was assessed by fractional area change of RV area in the apical 4-chamber view.…”

Echocardiographic Study of Right Ventricular Abnormalities in Adult Patients of Sickle Cell Anaemia

“…15 The peak instantaneous pressure gradient of Tricuspid Regurgitation (TR) was determined from the maximal continuous-wave Doppler velocity and the simplified Bernoulli equation (Abaci et al). 16 RESULTS  Out of the total 138 cases, 84 (60.86%) were sickle cell trait (AS) and 54 (39.14%) were sickle cell disease (SS).  RV-EDA was significantly higher in SS subjects compared to AS subjects (p < 0.0001).…”