People

Graduate Student	Dr. Kaushik Sampath
Division of Cardiology	Dr. Thura T. Harfi (OSU)
Division of Cardiology	Dr. Richard T. George (JHMI)
Project Supervisor	Prof. Joseph Katz

Outline

Left Ventricular (LV) flow characteristics in patients with LV thrombus using optimized echo PIV-PTV.

According to the CDC 2015, more than 800,000 people have a stroke each year and around 87% of them are associated with clot (thrombus) formation. Left ventricular thrombus (LVT) occurs commonly in patients with weak heart muscles (cardiomyopathy). However, the flow conditions that might contribute to the formation of LVT are not well established.

Contrast echo images obtained during routine scans are analyzed using optimized procedures that integrate image enhancement, particle image velocimetry (PIV) and particle tracking velocimetry (PTV) for mapping the LV flow in four patients with past or current LVT. Phase averaged velocity and vorticity distributions follow the flow evolution during the cardiac cycle, and are used for calculating statistical parameters of the LV vortex, including depth, strength and induced apical velocity.

Results

 

Sample phase averaged velocity and vorticity magnitude contours overlaid by the velocity vectors on a patient’s contrast echo sequence through the cardiac cycle. The blood inflow is marked with the rolling up of the LV vortex that subsequently decays and fragments as it moves towards the apex of the LV. The vortex induced flow at the apex plays a key role in whether a clot would develop at the apex or not.

Publications

Sampath, K., Harfi, T.T., George, R.T. and Katz, J., 2018. Optimized time-resolved echo particle image velocimetry–particle tracking velocimetry measurements elucidate blood flow in patients with left ventricular thrombus. Journal of Biomechanical Engineering, 140(4).

Sampath, K., Harfi, T. T., George, R. T., & Katz, J. (2016). Flow in patients with left ventricular thrombus using optimized echo PIV-PTV. Bulletin of the American Physical Society, 61.

Sampath, K., Abd, T. T., George, R. T., & Katz, J. (2015). Particle tracking velocimetry using echocardiographic data resolves flow in the left ventricle. Bulletin of the American Physical Society, 60.