Abstract 16424: Reliability and Validity of Grading of Intra-Pulmonary Shunting by Contrast Transthoracic Echocardiography in Hepatopulmonary Syndrome
Background: Contrast transthoracic echocardiography (C-TTE) with injection of agitated saline detects intra-pulmonary vascular dilatation (IPVD) in patients with advanced liver disease, necessary to diagnose hepatopulmonary syndrome (HPS). However, whether the reliability and validity of grading the severity of IPVD by C-TTE have not been evaluated.
Methods: We reviewed C-TTE images from consecutive Pts with HPS evaluated between 1985–2009 wihtout knowledge of other clinical information. Severity of IPVD was defined as none (no microbubbles visualized in left sided chambers), mild (few microbubbles visualized in left sided chambers without change in density), moderate (microbubbles in left sided chambers <50% density of right sided chambers), or severe (microbubbles in left sided chambers ≥ 50% density of right sided chambers).
Results: A total of 72 Pts (mean age 48 ± 14 yrs; 44 males) underwent 86 C-TTEs during the study period. Ejection fraction was preserved in all patients (66% ± 5%), with mean cardiac index 3.88 ± 1.14 L/min/m2. C-TTE was negative in 5 Pts (6%); IPVD was mild in 15 (17%), moderate in 22 (26%), and severe in 44 (51%). Intra-observer agreement was excellent (κ = 0.75, p < 0.01) and inter-observer agreement was good (κ = 0.61, p < 0.01). Increased severity of IPS by C-TTE was associated with more hypoxemia and increased A-a gradient (Table). Of 53 Pts who also underwent pulmonary perfusion study, IPVD by C-TTE was associated with severely increased shunt index in Pts with severe IPVD (p<0.01), but did not distinguish between Pts with mild or moderately increased shunt index (p= 0.97).
Conclusions: Severity of IPVD by C-TTE is a reliable measure and is associated with increased hypoxia and A-a gradient. This suggests that C-TTE is an accurate method to determine severity of IPVD in Pts with HPS.
- © 2010 by American Heart Association, Inc.