|By experience, the following main reasons can be listed:
Unsuitability of the adjustment kit with the implanted valves:
Be sure that the Sophy® adjustment kit (Ref RS5) is used for a Sophy® valve, and a Polaris® adjustment kit (Ref. PAK or Ref PAK-2) is used for a Polaris® valve.
Incorrect handling of the adjustment kit:
Please refer to the adjustment kit Instructions for Use or the details given in this Website to be sure to use the adjustment kit correctly.
The valve has been implanted upside down:
Check if the valve has been implanted correctly on the X-Ray (see questions above).
Valve implantation site is too deep beneath the skin surface: The rotor of the valve is blocked by biological deposit:
At the time of implantation, the depth below the skin should not exceed 10 mm for Sophy® and 8 mm for Polaris® valve. In addition, Polaris® must have been implanted on a hard bony surface. Otherwise, pressure adjustment can be impaired.
This is a known complication of the use of adjustable valves. The valve has to be explanted.