Pulsatile Flow Visualization - PIV, ECHO DOPPLER - Protomed Labs

 

Pulsatile Flow Visualization

 

 

 

 

 

Pulsatile Flow Visualization: Measured parameters

  • Qualitative pulsatile flow visualization
  • Quantitative pulsatile flow visualization – PIV
  • Flow Doppler measurements – echocardiography

Pulsatile Flow Visualization : Scope

  • Transcatheter valves
  • Biological valves
  • Mechanical valves
  • Venous valves
  • Valvular conduits
  • Assist ventricular devices
  • Any flow models

Pulsatile Flow Visualization : Applicable standards

Pulsatile Flow Visualization : Associated tests

Pulsatile Flow Visualization: Test method description

PROTOMED uses a proprietary and validated dual chamber pulsatile tester to assess heart valve hydrodynamic performance. Left ventricular stroke volume, heart rate and diastolic and systolic aortic pressures can easily be modified to customer’s requirements. The repeatability of measurements is ensured by a servo-control, which also monitors pressure and flow waveforms. The dual chamber pulsatile tester is used in conjunction with:

Pulsatile Flow Visualization: Particle Image Velocimetry.

The plexiglass visualization box, surrounding the anatomical aorta, ventricle and atrium silicon moulds, allows for the assessment of velocity fields using Particle Image Velocimetry. PIV is used to determine:

Death Flow: Areas of flow stagnations in the vicinity of the valve – Stagnant flow may induce potential blood clot formation during heart valve operation. 20 cycles max assumption: repetitive flow behaviour with standard video

High Velocity Gradients: High flow velocities in the vicinity of the valve may induce potential haemolysis and platelet activation. 20 cycles max assumption: repetitive flow behaviour with standard video

Vortical Flow: Vortical flows in the vicinity of the valve may induce potential haemolysis and platelet activation. 20 cycles max assumption: repetitive flow behaviour with standard video

Pulsatile Flow Visualization: Pulsed-wave Doppler

Verification of Bernoulli’s equation under in vitro physiological pulsatile flow conditions across the valve, ∆P= k (V12RMS-V22RMS). The system is aligned in parallel to the direction of the flow for velocity measurements. Pulsed-wave Doppler is used to measure velocities at points 1 and 2. Continuous wave Doppler is used to find the maximum velocity in the valve jet.

Pressure is monitored at specific points across the valve: 1 point upstream and 2 points downstream. Pulse duplicator configuration requires that the echo Doppler probe be placed in the aortic position. The following measurements are conducted: Pulsatile mode (2 measurements) & Continuous mode (average of 3 measures for each measure)