An improved aneurysm filler delivery system including a catheter and method of using the same is described. The catheter has at least one anchoring element at its distal tip region which is used to secure the catheter to a pre-implanted medical device, such as a stent, during the filling of an aneurysm. Such action prevents a buildup of pressure or of material from forcing the distal tip of the catheter to be forced from the aneurysm before the procedure is complete.