A system, comprising: a catheter, comprising: an insertion tube for insertion into a patient organ; a position sensor attached to a distal end of the catheter, wherein the position sensor is configured to provide a position of the distal end in the patient organ; a device, wherein the device is configured to move along the catheter; and a handle comprising a control, wherein the control is configured to navigate the device along the catheter to a target location in the patient organ; and a processor, wherein the processor is configured to: receive an anatomical image of the organ, wherein the anatomical image is acquired before inserting the catheter; and register the location of the position sensor with the anatomical image; characterised in that the catheter further comprises a marker configured to mark a target position of the control on the handle; and in that the processor is further configured to determine allowed boundaries for the target location relative to the anatomical image; estimate, based on a location of the position sensor, a target position of the control on the handle that corresponds to the target location of the device; and provide a marker position to mark the target position of the control on the handle. a catheter, comprising: an insertion tube for insertion into a patient organ; a position sensor attached to a distal end of the catheter, wherein the position sensor is configured to provide a position of the distal end in the patient organ; a device, wherein the device is configured to move along the catheter; and a handle comprising a control, wherein the control is configured to navigate the device along the catheter to a target location in the patient organ; and a processor, wherein the processor is configured to: receive an anatomical image of the organ, wherein the anatomical image is acquired before inserting the catheter; and register the location of the position sensor with the anatomical image; characterised in that the catheter further comprises a marker configured to mark a target position of the control on the handle; and in that the processor is further configured to determine allowed boundaries for the target location relative to the anatomical image; estimate, based on a location of the position sensor, a target position of the control on the handle that corresponds to the target location of the device; and provide a marker position to mark the target position of the control on the handle. an insertion tube for insertion into a patient organ; a position sensor attached to a distal end of the catheter, wherein the position sensor is configured to provide a position of the distal end in the patient organ; a device, wherein the device is configured to move along the catheter; and a handle comprising a control, wherein the control is configured to navigate the device along the catheter to a target location in the patient organ; and a processor, wherein the processor is configured to: receive an anatomical image of the organ, wherein the anatomical image is acquired before inserting the catheter; and register the location of the position sensor with the anatomical image; characterised in that the catheter further comprises a marker configured to mark a target position of the control on the handle; and in that the processor is further configured to determine allowed boundaries for the target location relative to the anatomical image; estimate, based on a location of the position sensor, a target position of the control on the handle that corresponds to the target location of the device; and provide a marker position to mark the target position of the control on the handle. receive an anatomical image of the organ, wherein the anatomical image is acquired before inserting the catheter; and register the location of the position sensor with the anatomical image; characterised in that the catheter further comprises a marker configured to mark a target position of the control on the handle; and in that the processor is further configured to determine allowed boundaries for the target location relative to the anatomical image; estimate, based on a location of the position sensor, a target position of the control on the handle that corresponds to the target location of the device; and provide a marker position to mark the target position of the control on the handle.