Ventricular Dyssynchrony Index: Comparison with Two-Dimensional and Three-Dimensional Ejection Fraction

Background: Left ventricular (LV) electromechanical coupling (synchrony) is important in the analysis of the systolic performance, especially for the indication of cardiac resynchronization therapy in patients with advanced CHF. Objective: To compare LV synchrony as analyzed by real-time three-dimensional (3D) echocardiography (ECHO) with LVEF measurements as obtained with 2D and 30 ECHO. Methods: Prospective study of 92 individuals (56 men, 47 +/- 10 years of age), of which 60 had normal heart structure (ECHO) and ECG (N group), and 32 had dilated cardiomyopathy (DCM group). Using 3D ECHO, LVEF volumes and dyssynchrony index (%DI) for 16 LV segments were measured. Using 2D ECHO, LVEF (Simpson's method), and LV systolic and diastolic. volumes were measured. Statistical analysis: Pearson's correlation coefficient, 95% Cl, linear regression model, Bland & Altman analysis, p < 0.05. Results: %DI ranged from 0.2900 to 28.1000 (5.2014 +/- 6.3281), 3D LVFF ranged from 0.17 to 0.81 (0.52 +/- 0.17); and 2D LVFF ranged from 0.3 to 0.69 (0.49 +/- 0.11). The correlation between DI and 30 LVEF was (r): -0.7432, p < 0.0001, Cl: -0.8227 to -0.6350, the linear relation between DI (x) and 3D LVEF (y) was y = 19.8124 + (-27.9578) x, p < 0.0001. The correlation between DI and 2D LVEF teas (r): -0.7012, p < 0.0001, CI: -0.7923 to -0.5797. Conclusion: In this case series, a good negative correlation was observed between LV electromechanical three-dimensional systolic coupling and LVEF as measured by echocardiography (3D and 2D).