Impaired blood flow efficiency was detected in patients with ESRD by using dissipative energy loss derived from vector flow mapping. The energy loss value could be a novel parameter for evaluating the ventricular workload of uremic hearts in terms of fluid mechanics.
Energy Loss Calculation by Vector Flow Mapping
Left ventricular intracardiac flow was recorded in the apical 4-chamber view by color Doppler imaging for 3 consecutive cardiac cycles. We maintained a frame rate in the range of 20 to 25 frames per second. All stored images were transferred into a vector flow mapping workstation (DAS-RS1 5.0; Hitachi-Aloka Medical Co) for offline analysis. The velocity component in the perpendicular direction to the echocardiographic Doppler beam could be calculated by a postprocessing computational algorithm11; thus, the actual velocity vector field was reconstructed. In each frame, the workstation computed the energy loss value in the region of interest from the velocity vector field by an algorithm established by Itatani et al.12 After aliasing correction, we manually delineated the LV cavity as the region of interest, and then the amount of energy that was dissipated as heat in the left ventricle was calculated.
Turbulência no sistema cardiovascular não é desejada.
Medidas da perda de energia derivadas das turbulências demonstram a perda de eficiência do ventrículo esquerdo.
Este pode ser um marcador precoce de lesão?
Tecnologia ainda nascente, precisa de mais marcas atuando e desenvolvendo.
Mas mostra que a ecocardiografia têm muito o que desenvolver ainda.