US Patent 7004937 Wire reinforced articulation segment

A device for steering a cardiac cryoablation catheter through the vasculature of a patient includes separate first and second deflection members that connect a tip member to the distal end of a catheter tube. Importantly, the first deflection member has a first flexural modulus, and the second deflection member has a second flexural modulus that is greater than the first flexural modulus. Also included is a control wire for pulling the tip member toward the catheter tube. In response, the first and second deflection members differentially deflect, according to their respective flexural moduli, to move the tip member for steering the catheter through the vasculature.