A robotic catheter system (10), the system comprising a cassette (22, 300) including a cassette housing (42, 316), the housing including a front end, a rear end, a first channel (364) and a second channel (366), wherein the cassette includes a first pair of engagement surfaces (426, 428) configured to impart axial movement to a guide wire (50, 301) retained in the first channel (364), wherein the guide wire extends out of a rear of the housing and exits a front end of the housing (42, 316)； and a second pair of engagement surfaces (472, 747) configured to impart axial movement to a catheter device (54, 303) retained in the second channel (366)； wherein the catheter device exits the front end of the cassette housing over the guide wire； wherein the second channel is arranged at an angle with respect to the first channel； and a motor drive base (22, 302) comprising one or more drive motors located in the base.
