Impella CP Catheter Position Alarms
The Automated Impella Controller continuously monitors the catheter based on the placement signal and the motor current.
- Placement signal: Is the signal characteristic of aortic or ventricular pressure?
- Motor current: Is the signal “pulsatile” or “flattened”?
If the system alarms with one of the positioning alarms described in this section, fluoroscopic imaging is the best method for confirming position. You can also use TEE, TTE, or a standard chest x-ray.
If the Impella® Catheter is either partly (just the pigtail) or completely in the ventricle, reposition the catheter under imaging guidance.
Correct Position
If the Impella CP Catheter is in the correct position, the placement screen will appear as shown on the left.
Catheter in ventricle
If the Impella CP Catheter is fully in the ventricle, the following alarm will appear:
- Impella Position In Ventricle
In this situation, the placement screen will appear.
Actions to take
- Under fluoroscopic or echocardiographic guidance, if available, reduce the P-level to P-2 and carefully pull back the Impella® Catheter until the aortic waveform signal is showing.
- When you see the aortic waveform signal, pull the catheter back an additional 4 cm.
Catheter in the Aorta
If the Impella Catheter is completely in the aorta or if the inlet and outlet areas are in the ventricle and the open pressure area is in the aorta, the following alarm will appear:
- Impella Position Wrong
In this situation, the placement screen will appear as shown.
Actions to take
- Under fluoroscopic or echocardiographic guidance, determine the Impella® Catheter position.
- Reduce the P-level to P-2 and reposition the catheter as necessary.
Low Native Heart Pulsatility
When a patient has poor native ventricular function, the placement signal may remain pulsatile; however, the amplitude will be dampened. In a situation of low native heart pulsatility, the Automated Impella® Controller may not be able to determine the catheter position. You may see the following indication on the home screen:
- Impella Position Unknown
In this situation, the screen will appear as shown.
Actions to take
- Assess cardiac function
Impella Catheter Outlet Area on or Near Aortic Valve
If the Impella CP Catheter outlet area is on or near the aortic valve, the catheter may be too deep in the ventricle. The following alarm will appear:
- Impella Position Wrong
Actions to take
- Assess and adjust Impella® Catheter position under fluoroscopic or echocardiographic guidance, if available.
- If fluoroscopic or echocardiographic guidance is not available, reduce the P-level to P-2 and gently pull the catheter back 2 cm to see if the condition resolves.
