Catheter apparatuses, systems, and methods for achieving neuromodulation by intravascular access. A treatment device has a pre-formed helical therapeutic assembly with spaced-apart proud portions that are offset with respect to the pre-formed helical shape when in a deployed configuration. The therapeutic assembly includes a plurality of energy delivery elements carried by and associated with the proud portions such that, in the deployed configuration, the proud portions are configured to position the energy delivery elements in apposition with an inner wall of a target blood vessel. The energy delivery elements can deliver energy across the inner wall of a renal artery, for example, to heat or otherwise electrically modulate neural fibers that contribute to renal function.
