Change in renal hemodynamics after renal denervation in diabetic patients with resistant hypertension and chronic kidney disease
Authors: Manukyan M , Falkovskaya A , Mordovin V , Pekarskiy S , Zyubanova I , Tsoi E , Lichikaki V , Ryabova T 
Published: October 2021

Abstract

Background
There are very few data on the initial features of hemodynamics and its changes after renal denervation (RDN) in patients with resistant hypertension (RHTN) and type 2 diabetes mellitus (DM), depending on the presence of chronic kidney disease (CKD), and the mechanisms of this effect require further study.

Purpose
To assess the features of renal hemodynamics and its change after RDN in patients with RHTN with type 2 DM, depending on the presence or absence of CKD.

Methods
In the study were included 38 patients with RHTN with type 2 DM (mean age 60.6±8.1 years, 14 men, 24-hour systolic / diastolic blood pressure (24-hr SBP/DBP) 160.9±16.5 / 82.2±11.3 mm Hg, mean HbA1c 7.87±1.62%), of which CKD occurred in 18 pts. (eGFR – 47.1 ml/min/1.73 m2), and 20 pts. without CKD (eGFR – 80.3 ml/min/1.73m2). All patients underwent baseline office and 24-hr BP measurement with calculation DBP/SBP ratio (D/S ratio), Doppler ultrasonography, serum creatinine, estimated glomerular filtration rate (eGFR) (CKD-EPI formula), urinary albumin excretion (UAE). The six-month follow-up period was completed by 14 patients in the group with CKD and 18 patients without CKD.

Results
At baseline, patients with CKD compared with those without CKD had higher pulse BP (82.2±10.0 versus 75.6±15.9, p=0.061), renal resistive indices (RRI) (0.78±0.06 versus 0.69±0.05, p=0.001 in the main renal arteries (RA); 0.73±0.07 versus 0, 63±0.06, p=0.001 in segmental RA) and significantly lower level of D/S ratio (0.49±0.06 versus 0.53±0.06, p=0.040). At the same time, the frequency of increased RRI (&gt;0.70) in the CKD group was almost 14 times higher than in those without CKD (73% and 5.3%, respectively, p&lt;0.001).After RDN, patients with CKD showed a significant decrease in SBP (−10.7 mm Hg, p=0.008) and an insignificant decrease in DBP (−3.9 mm Hg, p=0.118). In group without CKD, on the contrary, there was an insignificant decrease in SBP (−7.6 mm Hg, p=0.102) and a significant decrease in DBP (−5.5 mm Hg, p=0.030). The D/S ratio tended to increase in the group of CKD patients (p=0.08), whereas these indicators did not change significantly in the group without CKD. Additionally, there were a positive dynamics of RRI (decrease &gt;0.05) in patients with CKD, the frequency of which was almost 4 times higher than that in persons without CKD (43% and 11%, respectively, p=0.049). Moreover, a decrease in RRI correlated with an increase in the D / S ratio of both the main RA (R = 0.50; p=0.005) and in segmental RA (R = 0.40; p=0.028). There were no significant changes in UAE and serum creatinine in both groups.

Conclusions
Thus, CKD in patients with RHTN with type 2 DM is characterized by a significant increase in renal vascular resistance, while RDN in this patients, in contrast to patients without CKD, can be an effective therapeutic option not only for BP reduction, but also for improvement of renal hemodynamics.

Funding Acknowledgement
Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Russian Foundation for Basic Research