Estimation of Right Atrial Pressure from the Inspiratory Collapse of the Inferior Vena cava in Pediatric Patients

Objective: paucity of data exists between mean right atrial pressure (rap) and inferior vena cava (ivc) size and collapsibility in pediatric patients with congenital heart disease.methods: in a prospective study, fifty consecutive pediatric patients with different congenital heart diseases who had right side cardiac catheterization were studied, comparing right atrial pressure with simultaneous m-mode echocardiographic measurement of inferior vena cava diameter. mean age of the patients was 4.96±4.05 years (30 male and 20 female). patients were categorized into two groups according to their right atrial pressure (rap) as measured by cardiac catheterization: group 1 (40 patients) were those with mean rap <8 mmhg and group 2 (10 patients) who had a mean rap³ 8 mmhg.findings: in m-mode echocardiography ivc size was statistically different (p=0.004 and 0.009) in inspiration and expiration in the two groups. mean rap was estimated to be > 8 mmhg when ivc diameter in inspiration was >3.6 (sensitivity of 100%, specificity of 47.5%, +lr=1.9) or if ivc diameter was >6mm in expiration (sensitivity of 70%, specificity of 87%, +lr=4.67). conclusion: this study showed that measurement of ivc size in inspiration and expiration can be used as a reliable method for estimation of mean right atrial pressure.