Disclosed is a guidewire stop configured to lock a medical device onto a guidewire. The guidewire stop comprises a locking element, an actuator coupled to the locking element and a locking tube, wherein at least a section of the guidewire and at least part of the locking element or actuator pass through the locking tube. Further disclosed is that the locking tube comprises an unlocking element configured to unlock the medical device from the guidewire. The disclosed guidewire stop has at least the following three configurations:—an initial unlocked configuration in which the guidewire stop and the medical device are movable relative to the guidewire；—a first locked configuration in which the guidewire stop and the medical device are not movable relative to the guidewire； and—a first unlocked configuration in which the guidewire stop and the medical device are movable relative to the guidewire.
