The need for and the challenges of measuring renal sympathetic nerve activity.

Renal denervation (RDN) was primarily developed to treat hypertension and is potentially a new method for treating arrhythmias. Because of the lack of a standardized protocol to measure renal sympathetic nerve activity, RDN is administered in a blind manner. This inability to assess efficacy at the time of treatment delivery may be a large contributor to the ambiguity of RDN outcomes reported in the hypertension literature. The advancement of RDN as a treatment of hypertension or arrhythmias will be hampered by the lack of delivery assessment, a deficiency that the cardiovascular electrophysiology community, with its expertise in recording and mapping, may have a role in addressing and overcoming. The development of endovascular recording of renal nerve action potentials may provide a useful accessory tool for RDN. Innovation in this area will be crucial as we as a community reconsider the therapeutic value of RDN.