Two-dimensional strain echocardiography-derived left ventricular ejection fraction, volumes, and global systolic dyssynchrony index: Comparison with three-dimensional echocardiography

Background: Three-dimensional (3D) echocardiography is the most accurate echocardiographic method for ventricular chamber quantification. It is unclear how two-dimensional (2D) techniques perform against 3D technology and whether 2D methods can be extrapolated to obtain 3D data.

Methods: Retrospective review of transthoracic echocardiography was performed, with comparison of ejection fraction (EF), end-diastolic volume (EDV), end-systolic volume (ESV), and 2D strain-derived global longitudinal strain (GLS) and synchrony index.

Results: One-hundred patients were identified. Using 3D echocardiography as reference standard, good correlation was noted with 2D strain-derived EF (r = 0.89, P < 0.01) and with 2D standard biplane EF (r = 0.90, P < 0.01) and similarly for EDV (r = 0.84 and r = 0.81, respectively, both P < 0.01). Two-dimensional strain-derived EDV by 8% and 2D biplane-derived EDV underestimated by 8% (P < 0.01). In relation to 3D EF, 2D strain underestimated by 2% and 2D standard biplane overestimated by 2% (P < 0.01). There was a negative correlation between GLS and 3D EF (r = 0.84, P = 0.001). On multivariate analysis, 3D EF could be derived from 2D strain [3D EF = 34.345 + (0.125 * EDV) + (-0.289 * ESV) + (-1.141 * GLS)]. Three-dimensional echocardiography-derived synchrony parameter (ie, standard deviation from mean time to minimum systolic volume from 16 subvolumes) did not correlate with 2D strain-derived synchrony index (r = 0.171).

Conclusions: Two-dimensional standard biplane and 2D strain EF and EDV strongly correlate with 3D EF and EDV. Although 2D methods are predictive of 3D findings, over- and underestimations may occur. Three-dimensional echocardiography should be used when available.