Patent ID: 8414604

Claim:
A catheter for performing a procedure at a treatment site in the lumen of a blood vessel, the blood vessel having a diameter D at the treatment site, the catheter comprising: an elongate tubular shaft having distal and proximal ends and a sidewall defining a lumen, the elongate tubular shaft having a proximal bend, a distal bend and a hinge element, the proximal bend defining a first undeflected angle prior to insertion of the elongate tubular shaft into the lumen of the blood vessel and a first deflected angle greater than the first undeflected angle when the elongate tubular shaft is contained within the lumen of the blood vessel, the distal bend defining a second undeflected angle greater than the first undeflected angle prior to insertion of the elongate tubular shaft into the lumen of the blood vessel and a second deflected angle greater than the second undeflected angle when the elongate tubular shaft is contained within the lumen of the blood vessel, the hinge element being spaced proximally of the distal end of the elongate tubular shaft and distally of the distal bend, the distal bend being positioned between the proximal bend and the hinge element, a distal portion of the elongate tubular shaft extending between the hinge element and the distal end of the elongate tubular shaft and a mid portion of the elongate tubular shaft extending between the hinge element and the proximal bend, the distal portion including a window extending through the sidewall between the hinge element and the distal end of the elongate tubular shaft; and a working element disposed within the lumen of the elongate tubular shaft, the working element configured for performing the procedure through the window at the treatment site, the first and second undeflected angles being selected to form a maximum excursion of the elongate tubular shaft between the proximal bend and the hinge element greater than diameter D such that the window is urged against a wall of the vessel at the treatment site.