High salt intake did not diminish beneficial effect of renal denervation on blood pressure, kidney function and metabolic profile - croatian real-life study

Objective: Last trials clearly documented and confirmed the efficacy of renal denervation (RDN) on decrease of blood pressure (BP). Our aim was to analyze the effects of RDN beyond BP lowering in truly resistant hypertensive patients in real-life conditions. Design and method: Out of 31 truly resistant patients whose secondary forms of hypertension were ruled out and were enrolled into the Croatian Spyral RDN registry, 18(10 m, 8 w, average age 49.3) were eligible for analysis. Office BP, ABPM, central BP and PWV were measured with Omron M6, Mobilograph and Sphygmocor devices, respectively. Albuminuria and salt intake were determined from 24-h urine samples, eGFR using the CKD Epi equation. Sympathetic/parasympathetic activity was measured with an ANX-3.0 ANSAR device. All RDN procedures(Spyral Medtronic) were done by one physician (average number of ablation spots was 41/procedure). Patients were examined day before and that day, 1,3,6, and 12 months after the RDN. Reponse was drop of office systolic BP by 10 mmHg or more 6 months after RDN. There were no differences in the RDN procedure between responders and non-responders. Results: Office and ABPM values dropped the day after RDN and remained significantly lower at the end of the follow-up (6.5/-5.5 and -16.2/9 mmHg, respectively). The effect of RDN on BP was not abolished with high salt intake(15.5 g/day at the end of follow up). eGFR remained stable, and even slight improvement was observed at the end of follow-up(+8.4 ml/min/1.72m 2 ); albuminuria significantly decreased (-115 mg/day). All metabolic parameters (lipids, uric acid) improved at the end of follow-up. LFa/RFa decreased the day after RDN and remained lower during the follow-up period. After RND central systolic BP and Aix decreased more in responders than in non-responders (-12.8 vs. -7.3; -7 vs. -2.6) while PP amplification was improved in responders (1.22 to 1.33) but decreased in non-responders (1.33 to 1.25). Conclusions: In real-life circumstances, BP significantly decreased after RDN despite large salt ingestion. eGFR and albuminuria improved as well as metabolic parameters at the end of follow-up and all of the beneficial changes run in parallel with observed decrease in sympathetic activity.