Navigation system

The invention relates to a navigation system for navigating an interventional device (11) like a catheter and an interventional system comprising the navigation system. A position and shape determining unit (13) determines and stores a first position and shape of the interventional device within a living being (9) during a first interventional procedure like a first chemoembolization session and determines a second position and shape of an interventional device within the living being during a subsequent second interventional procedure like a second chemoembolization session. During the second interventional procedure the interventional device is navigated based on the stored first position and shape and based on the second position and shape. This allows considering during the second interventional procedure the path of the interventional device used during the first interventional procedure. In particular, this allows navigating the interventional device along the same path during the first and second interventional procedures.