Multi-directional steerable catheter

A method of accessing a target site in a vessel of a patient, said method comprising the steps of:

• providing a steerable catheter comprising:
• a tube (2) having a proximal end (4), a distal end (5), and a lumen extending therebetween, said tube (2) having a first segment (2d) proximate said distal end and second segment (2w) that extends proximally from said first segment (2d) toward said proximal end,
• a first pull wire (12) disposed within a first side lumen of the tube (2) and a second pull wire (13) disposed within a second side lumen of the tube (2), and extending from the distal end (5) to the proximal end (4) of the tube (2), said first and second pull wires comprising first and second wound segments (12w, 13w) which are wound about a longitudinal axis of the tube in the second segment (2w) of the tube, with the first wound segment (12w) and the second wound segment (13w) dispersed circumferentially about the longitudinal axis of the tube (2);
• wherein
• the wound segments (12w, 13w) are configured to reduce whipping when the tube (2) is rotated around the longitudinal axis of the tube (2),
• a handle (3) fixed to the tube (2), said handle comprising:
• means for selectively tensioning the first pull wire without tensioning the second pull wire, or tensioning the second pull wire without tensioning the first pull wire, to provide bidirectional steering of the deflectable segment;
• inserting the steerable catheter into a vessel of the patient, and navigating the steerable catheter through the vessel of the patient until the first segment of the tube is disposed proximate the target site and the second segment is disposed across a curve in the vessel;
• and
• operating one or both of the pull wires to deflect the first segment of the tube;
• and
• rotating the tube about the long axis of the tube (2) while the steerable catheter is disposed within the vessel.