A pre-curved catheter tube of a catheter assembly or other elongate medical device and methods for forming such a device using a heating procedure is disclosed. Pre-curving of the catheter tube is desirable to impart to the catheter assembly a desired positional configuration when the catheter assembly is inserted into a patient. The heating procedure may include heat sterilization procedures commonly used to sterilize medical devices prior to use. In one embodiment, therefore, a catheter assembly is disclosed, comprising an elongate catheter tube defining at least one lumen, and a tube constraint. The tube constraint is included with the catheter assembly and is configured to temporarily constrain the catheter tube in a curved configuration during a heating procedure of the catheter assembly so as to permanently form the catheter tube in the curved configuration after the heating procedure is complete and the catheter tube is released from the tube constraint.