Accurate, simplified and rapid three-dimensional echocardiographic volume quantifications: Comparison of different algorithms in symmetric and asymmetric left ventricular geometry

Objective: A comparative investigation of dynamic three-dimensional freehand echocardiography (D3DFE) and magnetic resonance imaging (MRI) was conducted to determine the accuracy and rapidity of the average rotation method (ARM) and the disk summation method (DSM) for volumetric analysis. Methods: In 15 patients with an asymmetric left ventricle and 12 normal subjects, end-diastolic and end-systolic left ventricular volumes were assessed by D3DFE and by MRI. Both DSM and ARM were used for volume determination. All echocardiographic readings were performed by two examiners blinded to each other and to the MRI results. The times needed for echocardiographic data acquisition and volumetric analysis with either algorithm were determined. Results: Correlation between ARM and MRI measurements was tighter than between DSM and MRI measurements (end-diastolic volume: r=0.95, P< 0.0001 versus r=0.94, P<0.0001 in asymmetric ventricles; and r=0.97, P<0.0001 versus r=0.96, P<0.0001 in symmetric ventricles; end-systolic volume: r=0.94, P<0.0001 versus r=0.93, P<0.0001 in asymmetric ventricles and r=0.96, P<0.0001 versus r=0.94, P<0.0001 in symmetric ventricles). In addition, ARM analysis was less time-consuming than DSM (6.4±0.4 min versus 7.6±0.3 min, P<0.05). Conclusions: For D3DFE, ARM is the most accurate and rapid approach to left ventricular volume determination. ARM benefits from advanced two-dimensional imaging and can be easily added to any standard transthoracic echocardiographic examination.