Transcatheter renal artery sympathetic denervation for resistant hypertension: an old paradigm revisited.

Resistant hypertension, defined as the failure to achieve target blood pressure despite concurrent use of 3 antihypertensive agents of different classes, is estimated to affect 20-30% of hypertensive patients. These patients are vulnerable to cardiovascular, cerebrovascular and renal complications. There is ample evidence that sympathetic nervous system hyperactivity contributes to the initiation, maintenance and progression of hypertension. The renal sympathetic nervous system, in particular, has been identified as a major culprit for the development and progression of hypertension, heart failure and chronic kidney disease in both preclinical and human studies. Traditional surgical sympathectomy proposed in 1940s was halted due to unacceptable operative risk and the emergence of anti-hypertensive medications. Recently, catheter-based renal sympathetic denervation by radiofrequency ablation has shown encouraging intermediate-term results with minimal complications in patients with resistant hypertension. This review summarizes the patho-physiological role of the renal sympathetic nervous system and the potential application of renal denervation therapy for the treatment of resistant hypertension.