Abstract 18481: Underestimation of Left Atrial Volume by 3-Dimensional Echocardiography Validated by Magnetic Resonance Imaging: A Meta-Analysis and Investigation of the Source of Bias
Background: Left atrial volume (LAV) is a fundamental prognostic factor in a variety of cardiac diseases including atrial fibrillation, heart failure and valvular diseases. Developing a repeatable, non-invasive, and accurate Methods of measuring LAV is crucial. 3-dimensional echocardiography (3DE) has achieved better estimation of LAV than 2DE. However, underestimation of LAV by 3DE has often been reported and no previous study synthesized these data. Accordingly, we performed a meta-analysis to reveal the existence and extent of the bias, and investigated the related factors.
Methods: Studies comparing LAV between 3DE and magnetic resonance imaging (MRI) published before June 4, 2010 were eligible. A meta-analysis with random effects model was performed to evaluate the systematic bias. Factors affecting the bias were investigated by univariable followed by multivariable analysis.
Results: A total of 15 studies including 416 subjects revealed underestimation of LAV by 3DE (−11.8ml; 95%CI [−16.2, −7.5], p<0.00001. Figure). Risk factors for underestimation included measuring minimal LAV and existence of cardiac disease, whereas less underestimation was observed when maximal LAV and/or healthy heart was evaluated. Increasing the number of plane included in the volumetry was associated with less underestimation (p<0.0001 for each comparison, Table).
Conclusion: Only by synthesizing a number of small studies as a meta-analysis could we display underestimation of LAV by 3DE and factors of the systematic bias. These data provide more detailed basis for analyzing and improving the accuracy of 3DE, an indispensable step towards further clinical application in LAV assessment.
- © 2010 by American Heart Association, Inc.