https://pubmed.ncbi.nlm.nih.gov/33605662/ portal hypertension

J Pediatr Gastroenterol Nutr. 2021 Feb 16.
doi: 10.1097/MPG.0000000000003079.Online ahead of print.
Reliable Detection of Intrapulmonary Shunts Using Contrast Enhanced Echocardiography in Children with Portal Hypertension or Portosystemic Shunt

Nathalie M Rock 1, Maurice Beghetti, Cécile Tissot, Jean-Pierre Willi, Maya Bouhabib, Valérie A McLin, Albane B R Maggio

Abstract

Objectives and study: The aim of this study was to analyze if contrast-enhanced echocardiography (CEE) is as reliable as lung perfusion scintigraphy (LPS) to detect intrapulmonary shunting (IPS) in children with portal hypertension (PHTN) or congenital/surgical portosystemic shunts (PSS) and to define the number of cardiac cycles required to exclude intrapulmonary shunting.

Methods: Inclusion criteria for this cross-sectional study were: 1) presence of PHTN or PSS diagnosed on abdominal ultrasound, 2) technically valid saline contrast echocardiography, 3) lung perfusion scintigraphy within 6 months of CEE. The number of cardiac cycles between right atrial opacification and the arrival of contrast in the left atrium was counted. We analyzed our CEE data at 3 and 5 cardiac cycles and compared them with LPS results.

Results: The study population was composed of 78 children (38 girls, 49%) aged 2.1 to 18.8 years (mean 9.8). 69 patients had PHTN (88%), and 9 had a PSS (11%). Eleven subjects (14%) presented evidence of IPS on lung perfusion scintigraphy (LPS). Peripheral oxygen saturation was lower in the subjects with IPS detected on LPS (95.3 ± 1.7 vs. 99.0 ± 1.4%; p < 0.01). Comparison of LPS with CEE before 3 and 5 cardiac cycles showed that CEE is highly specific (95.7%) as early as 3 cardiac cycles with a markedly better sensitivity (72.7%) when using 5 cardiac cycles. Furthermore, a negative study using 5 cardiac cycles ruled out IPS with a 95% negative predictive value. The cardiac cycle at which the bubbles appeared in the left atrium was inversely correlated to the shunt index measured using LPS (r = -0.563; p = 0.001).

Conclusion: CEE is sufficient for the screening of IPS in children with PHTN or congenital/surgical PSS, obviating the need for LPS.