Unaltered neurocardiovascular reactions to mental stress after renal sympathetic denervation

ABSTRACT

Background: The impact of renal denervation (RDN) on muscle sympathetic nerve activity (MSNA) at rest remains controversial. Mental stress (MS) induces transient changes in sympathetic nerve activity, heart rate (HR) and blood pressure (BP). It is not known whether RDN modifies these changes.

Purpose: The main objective was to assess the effect of RDN on MSNA and BP alterations during MS.

Methods: In 14 patients (11 included in analysis) with resistant hypertension multi-unit MSNA, BP (Finometer ®) and HR were assessed at rest and during forced arithmetics at baseline and 6 months after RDN.

Results: Systolic office BP decreased significantly 6 months after RDN (185 ± 29 vs.175 ± 33 mmHG; p = 0.04). No significant changes in MSNA at rest (68 ± 5 vs 73 ± 5 bursts/100hb; p = 0.43) were noted and no significant stress-induced change in group averaged sympathetic activity was found pre- (101 ± 24%; p = 0.9) or post-intervention (108 ± 26%; p = 0.37). Stress was associated with significant increases in mean arterial BP (p < 0.01) and HR (p < 0.01) at baseline, reactions which remained unaltered after intervention. We did not note any correlation between sympathetic nerve activity and BP changes after RDN.

Conclusion: Thus, in our group of resistant hypertensives we find no support for the hypothesis that the BP-lowering effect of RDN depends on altered neurovascular responses to stress.

KEYWORDS:

• Renal hypertension
• multi-unit muscle sympathetic nerve activity
• renal denervation
• sympathectomy
• arousal/physiology
• stress
• autonomic nervous system disorders

Disclosure of interests

BA has received study support from Medtronic and ReCor. BR has received study support from St. Jude Medical.

Additional information

Funding

This work was supported by grants from the Swedish Research Council, the Knut and Alice Wallenberg Foundation, the Emelle Foundation, the Gothenburg Medical Society, regional funding by Västra Götalandsregionen and federal funding under the LUA/ALF-agreement. The funding agencies had no role in the design of the study, analysis, interpretation of results, writing of the article, or approval of the article.