A virtual reality environment to visualize and manipulate 3D spatial human heart model and catheter in real-time was developed recently to interact with actual catheter to conduct electrocardiogram simulations. Since in the captured images, the catheter is loop-crossing, irregularly shaped, and often broken by the myocardium, it is difficult to catch the catheter tip in real-time. This paper describes an efficient algorithm for real-time catheter tip detection used in the simulator. After binarizing the catheter images and removing the noises, the width of the catheter is thinned to one pixel. In order to remove the reflection and refraction of light, the pixels of the whole catheter are labeled, and the feature patterns are extracted by using LUT method before detecting the catheter tip. Efficient algorithms are used to connect the broken parts and detect the loop crossings. The experimental results show that the average accuracy is above 79%. We keep the accuracy while optimizing the algorithm with higher performance.