Long-Term Effects of Renal Artery Denervation

Background and Objectives: Renal artery denervation (RDN) procedure is a broadly discussed method in the treatment of resistant hypertension. Many studies report short-term (3-12 months) results for blood pressure and arterial stiffness. The primary endpoints were changes in 24 h mean systolic blood pressure (BP) and office systolic BP 48 months after RDN. The secondary endpoints were changes in aortic pulse wave velocity and impact of polypharmacy on these variables. Materials and Methods: Renal artery denervation was performed in 73 patients treated for resistant hypertension; 49 patients remained in final analysis. Patient examination was carried out before the procedure, and subsequently at 3, 6, 12, 24, and 48 months later. Patients' antihypertensive and overall medication regimens were carefully analysed. Results: Mean 24 h arterial blood pressure lowered and was sustained at lower levels for up to 48 months; median (interequartile range-IQR) from 158(23.5)/100(14.2) to 140(26.5)/86(16.2) mmHg. Mean reduction in 24 h ambulatory systolic BP was -11 ± 25 mmHg (95% CI, -20 to -2; p < 0.001), while office systolic BP reduced by -7 ± 23 mmHg (95%CI, -24 to -1; p < 0.02). A significant reduction in median aortic pulse wave velocity 12 months after the procedure (drop from baseline 11.2 [3.15] m/s (95%CI 6.1 to 16.2) to 9.8 [2.1] m/s (95%CI 6.1 to 13.7; p = 0.002)). After 48 months, there was no worsening compared to the baseline level of 10.3 [4.0] m/s (95% CI 6.9 to 17.8) (p > 0.05). The total mean number of antihypertensive drugs remained unchanged: 5.97(±1.1) vs. 5.24 (±1.45). A higher number of pills after 48 months was associated with higher aortic pulse wave velocity (1-5 pill group: 8.1 ± 1.6 m/s; 6-10 pill group: 10.9 ± 1.8 m/s; >11 pill group: 15.1 ± 2.6 m/s) (p = 0.003). Conclusions: Antihypertensive effect after renal denervation lasts up to 48 months with no worsening of arterial stiffness compared to baseline. In our study, polypharmacy was associated with increased arterial stiffness 48 months after the procedure.