A navigation system for catheter-based interventions, the system comprising a processing device an angiogram x-ray system connected by data transfer connection to the processing device and capable of capturing angiographic images of a patient an electrocardiogram monitoring device that is also connected by data transfer connection to the processing device and to the x-ray system a medical instrument to be inserted into the area of the patient captured by the angiographic image a position capture module for getting position information about the position of the medical instrument, the unit connected by data transfer connection to the processing device, wherein the processing device is capable of triggering the capturing of the angiographic images as a roadmap and superimposing on the roadmap the position information about the medical instrument.