Quantification of Left Ventricular Mass Using Two-Dimensional Transthoracic Echocardiography - A Novel Method with High Accuracy and Reproducibility
Abstract Purpose Increased left ventricular mass (LVM) is a strong independent predictor for adverse cardiovascular events, but conventional echocardiographic methods used to assess and monitor individuals are limited by poor reproducibility and accuracy. We aimed to develop an echocardiographic method for LVM-quantification that is simple, reproducible and accurate. Methods The novel method adds the mean wall thickness to the left ventricular end-diastolic volume acquired using the biplane model of discs. The mean wall thickness is acquired from the parasternal short axis view. Cardiac assessment was performed using echocardiography followed immediately by cardiac magnetic resonance in 85 subjects with different left ventricular geometries, ranging from patients with various cardiac disorders (n=41) to individuals without known cardiac disorders (n=44). We compared the novel two-dimensional (2D) method to various conventional one-dimensional (1D) and 2D methods as well as three-dimensional (3D) echocardiography. Results The novel method had better reproducibility in intra-examiner (coefficients of variation (CV) 9% vs. 11-14%) and inter-examiner analysis (CV 9% vs. 10-20%) than the other methods. Accuracy of the novel method was similar to 3D (mean difference±95% limits of agreement, CV): Novel: 2±50g,15% vs. 3D: 2±51g, 16%; and better than the 1D-method by Devereux (7±76g, 23%). Conclusion The novel 2D-based method for LVM-quantification had better reproducibility than the other echocardiographic methods. Accuracy was similar to 3D and better than conventional methods. As endocardial tracings using the biplane model forms part of the standard echocardiographic protocol, the novel method can easily be integrated into any echocardiographic software, without substantially increasing analysis time.