A guide extension catheter (102) includes a push member (108) and a distal shaft (110). The push member includes a segment having a first surface (118) and a second surface (112) opposite the first surface. The segment includes a groove (128) in the first surface. The second surface is substantially flat. The distal shaft is coupled to the push member and includes a passageway (132). The segment of the push member including the groove is adjacent to the distal shaft.
