A medical system, includes an imaging apparatus, which includes an array of detectors, which define an imaging volume and form images of a region within a body of a patient that is positioned in the imaging volume. A movable bed transports the body of the patient through the imaging volume. An invasive probe is inserted into a lumen within the body of the patient. A tracking apparatus includes a field transducer positioned in the imaging apparatus and defining a tracking volume within the imaging apparatus, and generates an indication of a location of the invasive probe within the tracking volume responsively to an interaction between the field transducer and the invasive probe. A controller controls the movable bed in response to the location of the invasive probe indicated by the tracking apparatus.
