High-resolution transthoracic real-time three-dimensional echocardiography: Quantitation of cardiac volumes and function using semi-automatic border detection and comparison with cardiac magnetic resonance imaging Original Research Article

Objectives We sought to validate high-resolution transthoracic real-time (RT) three-dimensional echocardiography (3DE), in combination with a novel semi-automatic contour detection algorithm, for the assessment of left ventricular (LV) volumes and function in patients. Background Quantitative RT-3DE has been limited by impaired image quality and time-consuming manual data analysis. Methods Twenty-four subjects with abnormal (n = 14) or normal (n = 10) LVs were investigated. The results for end-diastolic volume (EDV), end-systolic volume (ESV), and ejection fraction (EF) obtained by manual tracing were compared with the results determined by the semi-automatic border detection algorithm. Moreover, the results of the semi-automatic method were compared with volumes and EF obtained by cardiac magnetic resonance imaging (CMRI). Results Excellent correlation coefficients (r = 0.98 to 0.99) and low variability (EDV −1.3 ± 8.6 ml; ESV −0.2 ± 5.4 ml; EF −0.1 ± 2.7%; p = NS) were observed between the semi-automatically and manually assessed data. The RT-3DE data correlated highly with CMRI (r = 0.98). However, LV volumes were underestimated by RT-3DE compared with CMRI (EDV −13.6 ± 18.9 ml, p = 0.002; ESV −12.8 ± 20.5 ml, p = 0.005). The difference for EF was not significant between the two methods (EF 0.9 ± 4.4%, p = NS). Observer variability was acceptable, and repeatability of the method was excellent. Conclusions The RT-3DE, in combination with a semi-automatic contour tracing algorithm, allows accurate determination of cardiac volumes and function compared with both manual tracing and CMRI. High repeatability suggests applicability of the method for the serial follow-up of patients with cardiac disease.