Analysis of left ventricular fluid dynamics in dilated cardiomyopathy by echocardiographic particle image velocimetry

OBJECTIVE: The aim was to analyze left ventricular (LV) fluid dynamics in dilated cardiomyopathy (DCM) by using echocardiographic particle image velocimetry (E-PIV). METHODS: Twenty patients with DCM and twenty healthy volunteers were examined. LV ultrasound contrast was administered by intravenous bolus injection. At least three dynamic contrast-enhanced echocardiographic images of cardiac cycles from apical three-chamber view and four-chamber view were obtained. The acquired echocardiographic image loops were processed off line by HyperFlow. RESULTS: In healthy hearts, the filling flow in the left ventricle finally comes to be a single large clockwise vortex, which smoothly redirects the blood to the outflow tract. Meanwhile, aberrant flow patterns are observed in the patients with DCM. In the DCM group, the vortex area (0.237 ± 0.063 vs 0.196 ± 0.129, P = .029), vortex depth (0.396 ± 0.134 vs 0.293 ± 0.143, P = .025), and vortex length (0.534 ± 0.089 vs 0.435 ± 0.176, P = .004) are significantly higher. The flow force angle (29.979 ± 8.208 vs 35.896 ± 6.044, P = .013) is significantly lower, and energy dissipation (0.975 ± 0.552 vs 0.578 ± 0.295, P = .006) is significantly higher. A negative linear relation is indicated between the following pairs of parameters: vortex depth and LV ejection fraction (EF) (r = -.350, P = .027); vortex length and LV EF (r = -.321, P = .044); energy dissipation and LV EF (r = -.523, P = .001). A positive linear relation is indicated between flow force angle and LV EF (r = .365, P = .021). CONCLUSION: E-PIV can effectively and quantitatively evaluate LV fluid dynamics in patients with DCM. LV fluid dynamics and LV systolic function interact with and affect each other.