Comparison of Left Atrial (LA) Volume Assessment by 2D Echocardiography (2DE) with Volumetric Analysis by Computed Tomography Coronary Angiography (CTCA)

Abstract

Background: Current guidelines suggest the use of three-dimensional left ventricular ejection fraction (3DLVEF) to assess left ventricular function, with its use favoured over Simpson's biplane method. It is also recommended that this value be cross checked with a visual estimation of left ventricular ejection fraction (LVEF). Aims: We sought to examine the accuracy of visual LVEF estimation by two experienced sonographers (SH, KS), compared to the gold standard obtained by 3DLVEF. Methods: A total of 363 consecutive patients had echocardiograms performed for a clinically indicated reason. All echocardiograms included a full volume threedimensional image acquisition from the apical windows. Both sonographers sequentially assessed visual LVEF first, then 3DLVEF on all cases in a blinded fashion. All measurements were performed using the AutoLVQ package on an EchoPac workstation. Results: Patient characteristics included age 57 ± 17 years, BMI 27.6 ± 5.9 kg/m 2 , 58% males and Simpsons biplane LVEF 58.3 ± 12.0% (range 15-87%). 3DLVEF was not considered feasible in 20% of patients and these cases were excluded from further analysis. There was an excellent correlation between visual LVEF between the two sonographers, with a Pearson's correlation coefficient r = 0.96 (95% CI 0.95-0.97), Bland Altman mean bias 0.2% (95% limits of agreement 6.9 to −7.4%). This was superior to the correlation between 3DLVEF between the two sonographers: r = 0.84 (95% CI 0.80-0.87), and between visual LVEF and 3DLVEF by each sonographer (KS: r = 0.83 [95%