Interventional radiology is a minimally invasive procedure where thin instruments, guidewires and catheters or stents are steered through the patient’s vascular system under X- ray imaging for treatment of vascular diseases. The complexity of these procedures makes training in order to master hand-eye coordination, instrument manipulation and procedure protocols for each radiologist mandatory. In this paper, we present a computer-based real-time simulation of interventional radiology procedures, which deploys a very efficient physics-based thread model to simulate the elastic behavior of guidewires and catheters. A fast collision detection scheme provides continuous collision response, which reveals more details of arterial walls than a centerline approach. Furthermore rendering techniques for realistic X-ray effect have been implemented. Our simulation structure is updated at a haptic rate of 500 Hz, thus contributing to physical realism.