Renal Sympathetic Denervation: Early Impact on Ambulatory Resistant Hypertension

Although guidelines recommend ambulatory blood pressure (BP) monitoring (ABPM), few data are available regarding the effects of renal denervation (RDN) on 24‐hour ABPM values. A total of 44 patients with mean systolic BP ≥135 mm Hg on ABPM despite adequate therapy were included. Basal systolic BP (SBP) and diastolic BP (DBP) were 154±11 mm Hg and 86±12 mm Hg, respectively. At 1 month, SBP and DBP were reduced to 146±18 mm Hg (P=.01) and 82±14 mm Hg and showed no further decrease up to 6 months. Only 55% of the patients responded to RDN (≥−5 mm Hg SBP), with a mean responder rate drop of 21/11 mm Hg. Neither the number of ablation points nor the amount of impedance drop was predictive of response. Only approximately half of patients with resistant hypertension responded to RDN. However, in these responders, a remarkable reduction of 24‐hour BP occurred as early as 1 month after RDN.

Hypertension is a major cardiovascular (CV) risk factor affecting one quarter of the adult population in Western societies.¹ Up to 12% of patients have resistant hypertension, defined as uncontrolled systolic blood pressure (SBP) despite therapy with ≥3 different antihypertensive agents, including a diuretic.², ³ Until now, surgical sympathectomy has been reported to significantly reduce blood pressure (BP) in resistant hypertension; however, perioperative morbidity was high.⁴, ⁵ By showing that percutaneous endovascular renal denervation (RDN) could represent a safe and effective alternative, the Symplicity HTN‐1 and HTN‐2 trials for resistant hypertension recently renewed interest in sympathectomy.⁶, ⁷ The proof‐of‐concept study with the Simplicity catheter has led to a series of trials—recently also conducted with improved catheter systems—to investigate the effects of this invasive approach.⁸, ⁹, ¹⁰, ¹¹ All studies consistently determined reductions in systolic and diastolic office BP values.⁸, ⁹, ¹⁰, ¹¹, ¹², ¹³ In addition, beneficial impact on sleep apnea, glucose intolerance, heart function, renal function, and rhythm disorders have been reported.¹⁴, ¹⁵, ¹⁶, ¹⁷ Until now, few data have become available with regard to the effects of RDN on resistant hypertension as verified in ambulatory BP monitoring (ABPM)⁸, ¹³, ¹⁸, ¹⁹, ²⁰the procedure recommended by guidelines and the literature for accurate evaluation of hypertension and for exclusion of pseudoresistance.²¹, ²² It has been clearly demonstrated that ABPM avoids overestimation and underestimation of BP and is also associated with risk prediction for CV events.²³, ²⁴, ²⁵ In the present study, we analyzed the effect of RDN on 24‐hour ABPM values up to a follow‐up of 6 months for better appraisal of BP changes.