Background: Renal nerve ablation (RNA) emerged as new therapeutic approach for treatment resistant hypertension. Measurement of the renal and sympathetic activity revealed a decrease in sympathetic drive to the kidney and small resistance vessels after RNA. However, the long-term consequences on renal perfusion and arterial function e.g. vascular remodeling are unknown.

Methods: In a pilot study 8 patients with treatment resistant hypertension were included and renal plasma flow (RPF) was non-invasively measured by magnetic resonance imaging with arterial spin labeling (MRI-ASI) before (day-1), after (day+1) and again after 1 months of RNA. In addition pulse wave analysis (central AIx@75, central systolic and diastolic BP) was assessed before (day-1) and after 6 months of RNA.

Results (median (interquartile range)): RPF did not differ between day-1 and day+1 (265 (242 – 267) versus 255 (236 – 289), p=0.811) as well as after 1 months (p=0.392) after renal nerve ablation. In accordance renal function (serum creatinine, eGFR, cystatin C) did not differ at any point of time. Central systolic (146 (133 – 155) versus 125 (116 – 136), p=0.046) as well as central diastolic BP (93 (87 – 112) versus 82 (79 – 88), p=0.046) was significantly reduced 6 months after RNA. Compared to day-1, there was a decrease in central AIx@75 after 6 months (25 (17 – 31) versus 19 (10 – 21), p=0.063) after RNA.

Conclusion: Thus, our data indicate that RNA reduce significantly central BP as well as improve vascular remodeling, which may impact on cardiovascular prognosis. Renal perfusion and function did not appear to be significantly changed.