Quantitative assessment of left ventricular size and function in cardiac transplant recipients: Side-by-side comparison of real time two-dimensional echocardiography, contrast-enhanced two-dimensional echocardiography, three-dimensional echocardiography, and contrast-enhanced three-dimensional echocardiography as compared to magnetic resonance imaging

Introduction: We evaluate the ability of 2D non-contrast-enhanced echocardiography (CE-echo), 2DCE-echo, 3D-echo, 3D non-CE-echo, and 3DCE-echo to evaluate allograft function and dimensions in orthotropic heart transplantation (OHT). Cardiac resonance (CMR) was used as reference. Methods: Twenty six consecutive OHT-recipients were prospectively recruited. Bland-Altman, Spearman rank, and concordance-correlation coefficients (CCC) were determined. Results: Good CCCs were found between the four modalities and CMR for ejection fraction (r >= 0.72/P < 0.001; r >= 0.77/ P < 0.001; r >= 0.51/ P < 0.23; r >= 0.75/P < 0.001, respectively). Highest intraclass correlation coefficient (ICC) was for 2D CE-echo(CCC = 0.77). End-diastolic volume(EDV) measurements statistically differed when 2D non-CE-echo, 2DCE-echo, and 3D non-CE-echo were compared with the cross-sectional imaging modalities, but they did not differ significantly from 3DCE-echo. End-systolic volume (ESV) and stroke volume (SV) differed statistically between the four modalities; however, SV measured by CMR and 3DCE-echo were comparable. Overall, 2D non-CE-echo, 2DCE-echo, and 3D non-CE-echo showed lower mean EDV, ESV, and SV than CMR. ICC was that of the ESV variable in the 4 techniques, with the values of the ICC of the 3DCE-echo technique superior to the rest. Overall, the best CCC were found for 3DCE(r = 0.88, 0.92 and 0.76 for EDV, ESV and SV, respectively). Conclusion: Routine use of 3DCE-echo may allow more comprehensive cardiac assessment in cardiac transplant recipients.