A method and device for exchanging catheters and microcatheters over exchange length wires is disclosed. The device consists of a hollow tube in a loop configuration attached to a base in which the extracorporeal segment of an exchange-length guidewire is inserted. The superior aspect of the tubular loop has a longitudinal slit which allows to and fro movement of catheters using a catheter holder having a handle that protrudes through the slit for easy manipulation.