Assessment of left ventricular systolic function by velocity vector imaging

Area of Science:

• Cardiology
• Medical Imaging
• Echocardiography

Background:

• Echocardiography is crucial for assessing left ventricular (LV) systolic function.
• Routine 2D echocardiography (2D ECHO) has limitations in accurately measuring ejection fraction (EF).
• Velocity Vector Imaging (VVI) is a novel technique using speckle tracking for endocardial border assessment.

Purpose of the Study:

• To evaluate the utility of Velocity Vector Imaging (VVI) for measuring left ventricular ejection fraction (LVEF).
• To compare VVI measurements with established methods like 2D ECHO and SPECT.
• To assess the accuracy and potential need for correction factors in VVI-derived EF.

Main Methods:

• Left ventricular ejection fraction (LVEF) was measured in 49 patients using VVI, 2D ECHO, and radionuclide-gated SPECT.
• Patient results were categorized based on LV systolic dysfunction severity.
• Statistical analysis, including correlation tests, was performed to compare the methods.

Main Results:

• VVI showed a mean EF of 35 ± 12.08%, significantly lower than SPECT (54.2 ± 19.51%) and 2D ECHO (50.3 ± 8.92%).
• Weak positive correlations were observed between VVI and SPECT (r=0.577) and 2D ECHO (r=0.573).
• VVI systematically underestimated EF and classified more patients with moderate/severe dysfunction (74.5%) compared to SPECT (34.7%).

Conclusions:

• Velocity Vector Imaging (VVI) is a feasible method for EF measurement.
• VVI demonstrated underestimation of LVEF compared to SPECT.
• Further studies are required to validate VVI accuracy and the necessity of a correction factor.