Devices, systems, and methods for catheterization through angionavigation, cardionavigation, or brain navigation to diagnose or treat diseased areas through direct imaging using tracking, such as radiofrequency, infrared, or ultrasound tracking, of the catheter through the patient' s vascular anatomy. A steerable catheter with six degrees of freedom having at least a camera and fiber optic bundle, and one or more active or passive electromagnetic tracking sensors located on the catheter is guided through the vascular system under direct imaging. The direct imaging can be assisted with at least one of MRA imaging, CT angiography imaging, or 3DRA imaging as the roadmap acquired prior to or during 3D stereoangiovision. The system comprises RF transceivers to provide positioning information from the sensors, a processor executing navigation software to fuse the tracking information from the tracking sensors with the imaging roadmap, and a display to display the location of the catheter on the roadmap.