Renal Nerve Stimulation-Induced Blood Pressure Changes Predict Ambulatory Blood Pressure Response After Renal Denervation

Abstract

Blood pressure (BP) response to renal denervation (RDN) is highly variable and its effectiveness debated. A procedural end point for RDN may improve consistency of response. The objective of the current analysis was to look for the association between renal nerve stimulation (RNS)-induced BP increase before and after RDN and changes in ambulatory BP monitoring (ABPM) after RDN. Fourteen patients with drug-resistant hypertension referred for RDN were included. RNS was performed under general anesthesia at 4 sites in the right and left renal arteries, both before and immediately after RDN. RNS-induced BP changes were monitored and correlated to changes in ambulatory BP at a follow-up of 3 to 6 months after RDN. RNS resulted in a systolic BP increase of 50±27 mm Hg before RDN and systolic BP increase of 13±16 mm Hg after RDN (P<0.001). Average systolic ABPM was 153±11 mm Hg before RDN and decreased to 137±10 mm Hg at 3- to 6-month follow-up (P=0.003). Changes in RNS-induced BP increase before versus immediately after RDN and changes in ABPM before versus 3 to 6 months after RDN were correlated, both for systolic BP (R=0.77, P=0.001) and diastolic BP (R=0.79, P=0.001). RNS-induced maximum BP increase before RDN had a correlation of R=0.61 (P=0.020) for systolic and R=0.71 (P=0.004) for diastolic ABPM changes. RNS-induced BP changes before versus after RDN were correlated with changes in 24-hour ABPM 3 to 6 months after RDN. RNS should be tested as an acute end point to assess the efficacy of RDN and predict BP response to RDN.

Keywords: 24-hour ABPM; drug-resistant hypertension; renal denervation; renal nerve stimulation.