Background: Overactivitiy of the sympathetic nervous system has been found to play a pivotal pathogenetic role in the development of arterial hypertension and chronic kidney disease (CKD). To treat hypertension, renal denervation (RDN) emerged an adjacent therapeutic option. This analysis of the ERLANGER registry aimed of comparing the blood pressure (BP) lowering effects and safety of RDN in patients with and without CKD. 

Methods: Radiofrequency or ultrasound device based renal denervation was performed in 47 patients with and 127 without CKD in our center. Office and 24h ABP (ambulatory blood pressure) were assessed after 6 and 12 months by validated devices. CKD was defined by clinical diagnosis, estimated glomerular filtration rate (eGFR: 15-59 ml/min/1.73m²; CKD-EPI formula) or repeatedly confirmed A2 albuminuria (≥ 30 mg/g creatinine in the spontaneous urine). To assess renal function our laboratory measurements included serum creatinine and eGFR according to CKD-EPI and the Creatinin/Cystatin-C formula.

Results: Until 04/2022, 174 patients with a mean age of 59.0±10 were followed up for at least 12 months. eGFR was 55.8±21 ml/min/1.73m² in patients with CKD and 87.3±13 ml/min/1.73m² in patients without CKD according to the CKD-EPI formula. There was no significant eGFR decline in either of the groups during follow up according to any formula. In patients with CKD eGFR after 12 months was 54.4±23 ml/min/1.73m² (CKD-EPI, p=0.699 vs baseline). Office and 24h systolic and diastolic BP were significantly reduced from baseline in patients with or without CKD at all time points after RDN (all p<0.01). There was no significant difference in the reduction of 24h, day- and nighttime ABP between the 2 groups at any time point (see table below). To identify any potential predictors for BP reduction we splitted the study cohort according to the median systolic 24h ABP reduction after 6 months into responders and non-responders. In addition to 24h baseline systolic ABP we identified several predictors (all p < 0.05): patients with a high baseline office heart rate (HR), without T2D, without diuretic medication and current smokers were more likely to be responders. With exception of rare local adverse events (e.g. haematoma at the puncture site), we had no safety signals, especially in our patients with CKD, e.g. there was no dissection, embolism or periprocedural cardiovascular complications.

Conclusion: In our single center registry, we observed a similar BP reduction in 24h, day- and nighttime ambulatory BP as well as in office BP in patients with and without CKD at any time point up to 12 months. There was no safety signal related to RDN. In particular, we did not observe a significant eGFR decline in both CKD positive or negative patients. In conclusion, according to our data RDN is a safe and an effective treatment option for hypertensive patients with and without CKD.