1. A catheter apparatus, comprising: an elongated shaft extending along an axis and comprising a controlled flexure zone and an unrestrained flexure zone coupled to and extending distally from the controlled flexure zone, the elongated shaft sized and configured for intravascular delivery into a renal blood vessel; wherein the unrestrained flexure zone is configured to carry a thermal element, and wherein the thermal element comprises a single distal tip electrode having an atraumatic tip; wherein the controlled flexure zone is sized and configured for placement into contact against a first wall region of the renal blood vessel and, in response to application of a force applied by a remotely controlled element, for flexure relative to the axis in a predetermined radial direction away from the first wall region toward a second wall region of the renal blood vessel generally opposite to the first wall region; wherein the unrestrained flexure zone is sized and configured, when the controlled flexure zone is in flexure against the first wall region, for passive flexure in any plane relative to the axis to place a side of the thermal element into contact against the second wall region; and wherein the controlled flexure zone is configured to apply, when in flexure against the first wall region, through the unrestrained flexure zone a stabilizing force to the thermal element against the second wall region.