Semi-automated estimation of left ventricular ejection fraction by two-dimensional and three-dimensional echocardiography is feasible, time-efficient, and reproducible

PURPOSE: To compare two-dimensional (2D) and three-dimensional (3D) methods to estimate left ventricular ejection fraction (LVEF) with respect to feasibility, time consumption, and retest reproducibility.

METHODS: A total of 100 patients planned to undergo coronary artery bypass grafting and/or aortic valve replacement were included consecutively. 2D and 3D echocardiography was performed on all patients. Acquisition and analysis time as well as intra- and inter-examiner variability were assessed in 50 consecutive patients with 3 repeated echocardiographic examinations and analyses. LVEF was estimated by five different methods: uniplane, biplane, and single-beat triplane (SB3P), as well as semi-automated biplane (AutoEF) and 3D volumetric tracings (4D Auto LVQ). All methods were compared to Simpson's biplane method and feasibility was determined.

RESULTS: Feasibility of Simpson's uniplane method, Simpson's biplane method, AutoEF, SB3P, and 4D Auto LVQ was 97%, 92%, 86%, 70%, and 89%, respectively. All methods evaluated were 18%-33% faster (P < 0.001) than Simpson's biplane method (115 seconds, standard deviation 15 seconds). Compared to Simpson's biplane method mean LVEF was slightly underestimated by 4D Auto LVQ (-2 ± 8%, P = 0.02), but not significantly different when assessed by the other methods. AutoEF and 4D Auto LVQ showed the lowest test variability (intra-examiner coefficient of variation (CV) 10%-11%; inter-examiner CV 10%-12% vs intra-examiner CV 12%-18%; inter-examiner CV 12%-20%).

CONCLUSIONS: Estimation of LVEF by modern semi-automated 2D and 3D echocardiographic modalities is feasible, time-efficient, and reproducible.