A system for guiding an intravascular ultrasound catheter device comprising an ultrasound probe to a potential lesion in a vascular tree, comprising: a localization unit (6; 7) configured to provide position information of the ultrasound probe for an automated processing of the position information; an evaluation unit configured to receive a diagnostic image of the vascular tree (22; 31), determine values of at least one vessel parameter for a plurality of locations in the vascular tree (22; 31) on the basis of the diagnostic image, and identify at least one location in the vascular tree (22; 31) associated with an abnormal value of the at least one vessel parameter; a mapping unit configured to provide information about the at least one location for use in the automated processing of the position information; and a steering unit configured to automatically steer the intravascular ultrasound catheter device, wherein the automated processing of the position information comprises an automated steering of the intravascular ultrasound catheter device based on the position information by means of the steering unit; wherein the steering unit is configured to steer the intravascular ultrasound catheter device in an automated pullback procedure on the basis of information about the at least on location associated with the abnormal value of the vessel parameter; and wherein during the automated pullback procedure the steering unit is configured to compare a position of the ultrasound probe with the at least one location and to move the ultrasound probe with a first velocity and to move the ultrasound probe with a reduced second velocity at the least one location on the basis of the result of the comparison. a localization unit (6; 7) configured to provide position information of the ultrasound probe for an automated processing of the position information; an evaluation unit configured to receive a diagnostic image of the vascular tree (22; 31), determine values of at least one vessel parameter for a plurality of locations in the vascular tree (22; 31) on the basis of the diagnostic image, and identify at least one location in the vascular tree (22; 31) associated with an abnormal value of the at least one vessel parameter; a mapping unit configured to provide information about the at least one location for use in the automated processing of the position information; and a steering unit configured to automatically steer the intravascular ultrasound catheter device, wherein the automated processing of the position information comprises an automated steering of the intravascular ultrasound catheter device based on the position information by means of the steering unit; wherein the steering unit is configured to steer the intravascular ultrasound catheter device in an automated pullback procedure on the basis of information about the at least on location associated with the abnormal value of the vessel parameter; and wherein during the automated pullback procedure the steering unit is configured to compare a position of the ultrasound probe with the at least one location and to move the ultrasound probe with a first velocity and to move the ultrasound probe with a reduced second velocity at the least one location on the basis of the result of the comparison.