Experience of using multielectrode catheter systems to perform radiofrequency renal sympathetic denervation in patients with resistant hypertension: immediate procedural effects

Abstract

Aim. To investigate the baseline characteristics of patients with resistant hypertension (HTN) undergoing radiofrequency renal sympathetic denervation (RD) and to determine immediate procedural effects.Material and methods. During 2018-2019, two series of radiofrequency RD procedures were performed in patients with true resistant HTN using balloon-type (bipolar ablation) or spiral-type (unipolar ablation) multielectorde catheters. The basic demographic, clinical and laboratory characteristics of included patients were assessed. A comparative analysis of two groups was carried out depending on the type of catheter used. Dynamics of office systolic blood pressure (SBP) were assessed as ∆ between the two following timepoints: at screening and at hospital discharge. The safety of radiofrequency RD was assessed. Multiple linear regression was used to determine the factors associated with the ∆ of office SBP after radiofrequency RD.Results. A total of 48 patients taking 4 (4;6) antihypertensive drugs were sequentially included. Radiofrequency RD was performed with a balloon-type catheter in 27 patients (mean age, 56±12 years old; 12 males) and with a spiral-type catheter in 21 patients (50±14 years old; 8 males). Radiofrequency RD was significantly longer in the spiral catheter group than in balloon one (110 versus 60 minutes, p<0,001), as was the mean number of RF applications (24 versus 12, p=0,002). None of the patients had acute kidney injury after RD (creatinine ∆, -0,6 µmol/L; 95% CI [-3,97; 2,78]). A total of 4 patients had complications (3 femoral arterial pseudoaneurisms, one renal arterial dissection), all of which did not affect the average length of hospital stay (from 4 to 5 days). At discharge, there was a pronounced decrease in office SBP (adjusted for baseline characteristics) with the mean of -26 mm Hg (95% CI [-29; -23]). There were following main factors associated with the office SBP ∆: smoking status (positive), baseline office SBP (positive), and blood glucose (negative).Conclusion. Radiofrequency RD using multielectode catheters is characterized by favorable short-term hemodynamic effects. We have found novel potential predictors of these effects. Further research will focus on testing initial hypotheses in the long term.