Abstract 12026: Development of a Consensus Document to Improve Multi-Reader Concordance and Accuracy of AR Severity Grading by Echocardiography: A Study with Cardiac MRI Correlation
Introduction: Guidelines recommend a multi-parametric assessment of regurgitant valves. However, as no hierarchy is provided, discordant parameters if weighted differently by different readers can result in inter-observer variability.
Hypothesis: A hierarchical approach to aortic regurgitation(AR) severity grading by echo will improve multi-reader concordance and accuracy. The aims of the study were: 1) To assess magnitude and causes of inter-observer variability 2) To formulate a hierarchical consensus document with validation against expert read and cardiac MRI and 3) to evaluate if the consensus document improves concordance and accuracy.
Methods: 17 level 3 readers (11 US, 6 non US) graded 20 randomly selected AR cases and provided a usefulness score for each key echo parameter based on its impact on grading. A consensus document was subsequently formulated and validated against cardiac MRI and an expert group. Readers were updated with the consensus document and recalibrated using the same cases. Agreement was assessed by Randolph's kappa.
Results: Baseline agreement between the readers was suboptimal (kappa 0.5, Fig1) with lack of key parameter hierarchy contributing to the variability. A hierarchical consensus document was developed in which the diagnostic group constituted by elevated LVEDVI tiered higher than the specific group (holo-diastolic flow reversal, vena contracta width and LVOT/jet width ratio). Severe AI was defined by elevated LVEDVI with atleast one specific parameter in severe range. Recalibration of readers improved concordance (Fig 1) and accuracy relative to cardiac MRI with sensitivity improving from 60% to 100%.
Conclusion: Grading of chronic AR using a multiparametric approach has suboptimal multi-reader variability. A hierarchical consensus document improves concordance and accuracy in grading AR severity.
- © 2011 by American Heart Association, Inc.