Renal sympathetic denervation for treating resistant hypertension.
Systemic hypertension represents a significant global concern, because it contributes to vascular and renal morbidity, cardiovascular mortality, and economic burden, hence the impact of hypertension is a major issue in public health worldwide. Improving high blood pressure management is therefore fundamental to influencing clinical outcomes. Despite adherence to multiple available medical therapies, a significant proportion of patients has persistent blood pressure elevation, a condition termed "resistant hypertension". Renal sympathetic innervations contribute to lack of response of anti-hypertensive drugs through an imbalance of regulatory mechanisms. Renal afferent nerve fibers are responsible for sympathetic activation and contribute to blood pressure homeostasis while afferent signals from the kidneys are integrated at the central nervous system and enhance sympathetic nerve discharge. In this regard, a novel strategy that selectively removes these hypertensive contributors represents a new therapeutic opportunity. Recently, a catheter-based method to induce renal sympathetic denervation has been introduced into daily practice. Clinical evaluation of selective renal sympathetic denervation demonstrated a decrease of renal norepinephrine spillover and renin activity, an increase of renal plasma flow, and has confirmed clinically significant, sustained reductions in blood pressure in patients with resistant hypertension. This review summarizes the available data on the role of sympathetic activation in the pathophysiology of hypertension and the current concepts in transcatheter renal artery ablation with radiofrequency delivery for systemic hypertension. Suggestions regarding targets for future systemic hypertension management are also described.