Abstract: A catheter having a first magnet is guided into a pocket of air entrapped in a pumping chamber for an artificial heart using a probe having a second magnet, a Hall-effect sensor an electronic circuit and an indicator disposed thereon. The Hall-effect sensor generates a voltage signal that is related to the distance between the catheter tip and the probe tip and that is measured by the electronic circuit and thereafter used to actuate the indicator. The indicator indicates when the probe is close enough to the catheter such that the catheter tip has been magnetically captured by the probe tip. Once magnetically captured, the probe tip, while remaining outside of the pumping chamber, is used to guide the catheter tip to an elevated portion of the pumping chamber wherein the pocket of entrapped air is located. A vacuum generating device attached to a distal end of the catheter tube is then used to withdraw the air from the pumping chamber.