Abstract 13777: Validation of Left Atrial Functional Measurements Using Three-dimensional Echocardiography: Comparison With Cardiac Magnetic Resonance Imaging on Various Planes
Background: Using novel three-dimensional echocardiography (3DE) software, dynamic volume change of left atrium (LA) can be semi-automatically obtained without any geometric assumption throughout the cardiac cycle. Nowadays, functional parameters of LA calculated using 3DE time-volume curve has been already widely used in clinical practice; however, it has never been fully validated with the other modalities yet.
Methods: We simultaneously performed 3DE and cardiac magnetic resonance (CMR) in 37 patients (age 71±12 years) with heterogeneous heart diseases. Full-volume 3DE dataset was analyzed using offline software (4D Auto LVQ, EchoPAC, GE). Multi-slice gated CMR images of short-, vertical long-, and horizontal long-axis planes were obtained with a 1.5-T scanner (Philips), which were used to obtain LA volume curve (EWS, Philips). The maximal and minimal LA volume indices (LAVImax and LAVImin, respectively), and LA volume index before atrial contraction (LAVIpre-c) were determined from LA time-volume curve. Total LA emptying fraction was expressed as [(LAVImax - LAVImin) / LAVImax]. LA reservoir function was expressed as expansion index [(LAVImax - LAVImin) / LAVImin], and booster pump function as active emptying fraction [(LAVIpre-c - LAVImin) / LAVIpre-c].
Results: Regarding absolute LA volume, 3DE showed significant underestimation compared with CMR (Mean difference of LAVImax: 1.8-3.5 mL/m2, 3.6%-7.0% of mean value; LAVIpre-c: 5.6-7.8 mL/m2, 11.6%-16.4%; LAVImin: 4.2-5.7 mL/m2, 10.8%-14.7%). However, there was significant correlation with an acceptable degree (r=0.72-0.89) between all 3DE functional parameters and those by CMR with any plane (Figure). On all three LA functional parameters, the correlation coefficient with 3DE was the highest in CMR on short-axis plane compared to the other planes.
Conclusion: 3DE LA functional parameters can be accurate equivalently to CMR, especially on short-axis plane.
- © 2013 by American Heart Association, Inc.