Resistant
hypertension, defined as blood pressure (BP) remaining above goal despite the use of 3 or more
antihypertensive medications at maximally tolerated doses (one ideally being a
diuretic) or BP that requires 4 or more agents to achieve control, occurs in a substantial proportion (>10%) of treated hypertensive patients. Refractory
hypertension is a recently described subset of resistant
hypertension that cannot be controlled with maximal medical
therapy (⩾5
antihypertensive medications of different classes at maximal tolerated doses). Patients with resistant or refractory
hypertension are at increased cardiovascular risk and comprise the target population for novel
antihypertensive treatments. Device-based interventions, including carotid baroreceptor activation and renal
denervation, reduce sympathetic nervous system activity and have effectively reduced BP in early clinical trials of resistant
hypertension. Renal
denervation interrupts afferent and efferent renal nerve signaling by delivering radiofrequency energy, other forms of energy, or
norepinephrine-depleting pharmaceuticals through
catheters in the renal arteries. Renal
denervation has the advantage of not requiring
general anesthesia, surgical intervention, or device implantation and has been evaluated extensively in observational proof-of-principle studies and larger randomized controlled trials. It has been shown to be safe and effective in reducing clinic BP, indices of sympathetic nervous system activity, and a variety of
hypertension-related comorbidities. These include impaired
glucose metabolism/
insulin resistance,
end-stage renal disease,
obstructive sleep apnea,
cardiac hypertrophy,
heart failure, and
cardiac arrhythmias. This article reviews the strengths, limitations, and future applications of novel device-based treatment, particularly renal
denervation, for resistant
hypertension and its comorbidities.