1. A catheter apparatus, comprising: an elongated shaft extending along an axis, the elongated shaft having a proximal portion and a distal portion, wherein the elongated shaft comprises— a force transmitting section at the proximal portion of the elongated shaft; a transition section distal to the force transmitting section and having a lesser stiffness than the force transmitting section, wherein the transition section has a proximal region and a distal region; a first flexure zone comprising a deflectable tubular body extending from the distal region of the transition section, wherein the first flexure zone and the transition section comprise a circumferential cut pattern having a decreasing density of circumferential cuts toward the proximal region of the transition section; and a second flexure zone extending distally from the first flexure zone; and an energy delivery element coupled to the distal portion of the elongated shaft and configured to deliver energy to modulate a renal nerve at a treatment site within the renal artery.