An apparatus is disclosed including: an intracardiac pump device having a path for a guidewire extending through the pump device from a first opening to a second opening; and a lumen which extends from a first end located outside of the pump device, into the pump device through the first opening in the pump device, along the path for the guidewire, out of the pump device through the second opening, and to a second end located outside of the pump device. The lumen is configured to receive the guidewire such that when the guidewire passes through the lumen from the first end to the second end, the guidewire is positioned along the path.