Twenty-four-hour blood pressure monitoring to predict and assess impact of renal denervation

Abstract

The DENERHTN trial (Renal Denervation for Hypertension) confirmed the blood pressure (BP) lowering efficacy of renal denervation added to a standardized stepped-care antihypertensive treatment for resistant hypertension at 6 months. We report here the effect of denervation on 24-hour BP and its variability and look for parameters that predicted the BP response. Patients with resistant hypertension were randomly assigned to denervation plus stepped-care treatment or treatment alone (control). Average and standard deviation of 24-hour, daytime, and nighttime BP and the smoothness index were calculated on recordings performed at randomization and 6 months. Responders were defined as a 6-month 24-hour systolic BP reduction ≥20 mm Hg. Analyses were performed on the per-protocol population. The significantly greater BP reduction in the denervation group was associated with a higher smoothness index (P=0.02). Variability of 24-hour, daytime, and nighttime BP did not change significantly from baseline to 6 months in both groups. The number of responders was greater in the denervation (20/44, 44.5%) than in the control group (11/53, 20.8%; P=0.01). In the discriminant analysis, baseline average nighttime systolic BP and standard deviation were significant predictors of the systolic BP response in the denervation group only, allowing adequate responder classification of 70% of the patients. Our results show that denervation lowers ambulatory BP homogeneously over 24 hours in patients with resistant hypertension and suggest that nighttime systolic BP and variability are predictors of the BP response to denervation.