The present disclosure provides a medical device comprising a deflecting assembly configured to assist in deflecting a distal portion of a catheter shaft. The deflecting assembly may include a first rotatable member having a first diameter and a first pull wire coupled thereto and a second rotatable member having a second diameter smaller than the first diameter and a second pull wire coupled thereto, wherein the second rotatable member is coupled to the first rotatable member such that a center point of the second rotatable member is offset from a center point of the first rotatable member. The first and second rotatable members are configured such that rotation of the first rotatable member via the first pull wire causes rotation of the second rotatable member and second pull wire, thus resulting in deflection of a distal portion of the medical device.
