Accelerated Wear Testing (AWT)

Study the durability (repeated opening and closing) of a heart valve prosthesis under accelerated conditions.

Test Procedure

For devices which may experience an immediate total loss of function, testing is performed to a minimum of  400 million cycles. For devices with demonstrated gradual degradation function, testing is performed to a minimum of 200 million cycles. For devices without established clinical history or for submissions to certain regulatory bodies additional cycles may be required.

Specified differential pressure is maintained across the closed valve  for 5 % or more of a single cycle. Using ViVitro’s expertise and equipment the maximum pressure across the valve is minimized to avoid over testing the device.

Samples experience full range of leaflet/occluder motion  as measured under normotensive conditions under pulsatile flow. This determines the maximum speed at which a sample can run.

Devices shall be inspected (microscope, photographs, and high-speed video) and functionally evaluated under pulsatile flow at least every 50M cycles.

Equipment

• ViVitro Labs HiCycle, or other Accelerated Durability Tester(s)
• Durability Pressure Data Acquisition System
• High speed video recording system
• Manometer
• Thermometer
• Stroboscope

Measured Parameters

• Number of Cycles conforming to loading conditions (target pressures across the closed valve were attained for at least 5 % of each cycle)
• Sample pressure waveforms
• Opening and closing kinematics under highspeed video
• Photographic documentation of the appearance of the test sample at defined inspection intervals
• Hydrodynamic performance at defined inspection intervals

Scope

• Surgical Valves: SAVR, SMVR, SPVR, STVR
• Transcatheter Valves: TAVI / TAVR, TMVI / TMVR, TPVI / TPVRTMVR, TTVR / TTVI  and any other transcatheter valve
• Biological, Polymeric, mechanical valves, tissue engineered
• Artificial heart valves prosthesis
• Venous valves
• Valvular conduits
• Any valvular prosthesis
• Any cardiac repair device

Service Levels

• Standard Service
• Full Service
• Full Service with ISO 17025

Applicable Standards

• ISO 5840-2:2021
  Cardiovascular implants — Cardiac valve prostheses — Part 2: Surgically implanted heart valve substitutes

• ISO 5840-3:2021
  Cardiovascular implants — Cardiac valve prostheses — Part 3: Heart valve substitutes implanted by transcatheter techniques

Related Tests

• Durability Testing (Integrated Durability Assessment)
• Dynamic Failure Mode (DFM)
• Real-Time Wear Testing (RWT)
• Pulsatile Flow Testing – Hydrodynamic Performance
• Scanning Electron Microscopy (SEM) and Optical Inspection
• Simulated Use Pre-conditioning

OLE0909, QV-502