Objectives: In renal denervation (RDN), a wide range in the blood pressure (BP)-lowering effect has been reported. On the basis of the current knowledge of pathophysiology, we hypothesized that the BP-lowering effect of RDN would be inversely related to kidney function. Second, we investigated whether direct and indirect variables of the renin-angiotensin-aldosterone system (RAAS) and the sympathetic nervous system (SNS) would be related as well.
Methods: Sixty-seven patients from a prospective cohort of patients treated with RDN with completed 6 months follow-up were included. Data collected during routine standardized work-up before RDN were used: 24-h urine excretion of creatinine, albumin, sodium and catecholamines, plasma creatinine, renin activity and aldosterone, ambulatory BP-monitoring and a captopril challenge test. When considered well tolerated, antihypertensive drugs were stopped before these investigations.
Results: The BP-lowering was inversely related to estimated glomerular filtration rate (eGFR) in patients who stopped antihypertensive drugs prior to testing (ß: 0.46, P = 0.013). There was a positive relation between SBP at baseline and the BP-lowering effect of RDN (ß:-0.55 mmHg per mmHg, P < 0.001). Parameters related to the rennin-angiotensin system (aldosterone, captopril test) and the sympathetic nervous system (dipping pattern and catecholamines in urine) positively related to the BP-lowering effect of RDN.
Conclusion: The present explorative study shows an inverse relation between the BP-lowering effect of RDN and eGFR. Second, we found relations between variables of the RAAS and SNS with the BP-lowering effect of RDN. The data complement current concepts on pathophysiology of sympathetic hyperactivity and hypertension and may give some insight in the wide range of the effect of RDN.