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Deliver the Navvus® MicroCatheter, Equalize Signals, and Enter Venous Pressure
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| ACIST RXi System User’s Guide
901700-001,01 2019-09 English
Basic Operating Procedures
Note
Carefully place the Navvus MicroCatheter on the guidewire to avoid damage to the tip.
Avoid contact between the guidewire and the small pressure sensor that is just proximal
to the microcatheter tip.
Open the hemostasis valve fully to avoid damage to the Navvus MicroCatheter tip.
5. Advance the Navvus MicroCatheter over the wire and position it with the
radiopaque marker in the coronary ostium, 3 mm outside the tip of the
guide catheter.
WARNING
Do not disturb pressure sensing system elements during equalization or FFR recording.
6. Equalization must take place with the Navvus MicroCatheter distal tip
just distal to the guide catheter tip. Pressure is measured less than 3 mm
proximal from the marker band that is visible under fluoroscopy:
• Flush the guide catheter with saline solution.
• Verify that the Pa displayed on the ACIST RXi System matches the
reading on the hemodynamic monitor.
• Press the
Equalize
button.
• After equalization, the red and green waveforms should be
superimposed and the displayed Pd/Pa value should be stable at 1.00.
CAUTION
Verification of aortic and distal pressures is very important for the upcoming pressure
recordings. If the baselines are not equal at this point, a systematic error will be carried
through the FFR calculations.