Real time three‐dimensional echocardiographic quantification of left atrial volume in orthotopic heart transplant recipients: Comparisons with cardiac magnetic resonance imaging

Abstract Introduction The accuracy of real time three‐dimensional echocardiography (RT‐3DE) in evaluating left atrial volume (LAV) of heart transplant recipients against cardiac magnetic resonance (CMR) has not been reported. The aim of this study was to compare LAV with RT‐3DE with respect to CMR in heart transplant recipients. Methods Thirty‐one heart transplant recipients who received echocardiogram and CMR examination on the same day were prospectively enrolled. The maximal LAV, minimal LAV by RT‐3DE, and two‐dimensional echocardiography (2DE) were compared with CMR measurements. Inter‐technique comparisons included Pearson's correlation coefficient and Bland–Altman analysis. Reproducibility of 2DE and RT‐3DE technique was assessed by intra‐class correlation coefficient (ICC). Results RT‐3DE‐derived LAV values showed higher correlation with CMR than 2DE measurements in heart transplant recipients ( r = .93 vs r = .76 for maximal LAV; r = .91 vs r = .81 for minimal LAV). Two‐dimensional echocardiography underestimated maximal LAV by 10 ± 31 mL and minimal LAV by 26 ± 26 mL. Although RT‐3DE underestimated minimal LAV 15 ± 19 mL, no significant difference between RT‐3DE and CMR was observed in maximal LAV (RT‐3DE: 86 ± 22 mL; CMR: 89 ± 23 mL, P = .079), with a negligible bias of 3 mL. Inter‐observer and intra‐observer agreement were excellent for 2DE and RT‐3DE parameters. Conclusion Compared with CMR reference, RT‐3DE‐derived LAV measurements are more accurate than 2DE‐based analysis in heart transplant recipients, especially with regard to the assessment of maximal LAV. RT‐3DE may be a valid alternative to CMR for quantification LAV in heart transplant recipients.