Electrophysiology-based assessment of the procedural success of radiofrequency renal denervation. (25th November 2020)

• Record Type: Journal Article
• Authors: Pekarskiy, S; Baev, A; Mordovin, V; Falkovskaya, A; Zubanova, I; Sitkova, E
• Is Part Of: European heart journal. Volume 41:(2020)Supplement 2
• Publication Date: 2020-11-25
• Subjects: Hypertension: Device Treatment and Intervention; Cardiology -- Periodicals; Heart -- Diseases -- Periodicals; 616.12005
• DOI: 10.1093/ehjci/ehaa946.2783
• Languages: English
• ISSNs: 0195-668X

Abstract

Abstract: Objective: To assess whether electrode temperature and impedance change that are typically monitored during radiofrequency renal denervation (RDN) for safety reason may also be used as measures of the procedural success of the intervention. Methods: We conducted a prospective clinical study of the radiofrequency RDN in patients meeting criteria of true resistant hypertension. The RDN treatment included the trunk and major branches of the renal artery. To obtain simple easy-to-use electrophysiology measures of the procedural success of RDN we averaged the maximal values of the temperature and change of impedance across all single treatments with a full duration. Then we assessed the relation of the average change in impedance and average maximal electrode temperature during RDN to blood pressure (BP) lowering 6 month post-procedure using a linear regression analysis. Also, we compared the groups with "successful" and "unsuccessful" procedures according to whether the impedance decreased, on average, ≥10% during RDN, and, alternatively, on whether the average maximal temperature of the electrode was ≥50 C. Results: Of 65 treated patients 52 with quality recordings of the electrophysiology parameters during RDN completed 6-month follow-up. The mean 24-h systolic BP decreased significantly after RDN by −14.3 mmHg [95% CI: −8.7; −19.9]. The BP lowering was positively and significantly related to the decrease in impedance during RDN, r=0.35, p=0.013 and to less extent to the maximal electrode temperature, r=0.29, p=0.044. The 10% average drop in impedance predicted -9.9 mmHg decrease in 24-h mean systolic BP. According to group analysis the decrease of mean 24-h systolic BP was powerful in those with average decrease in impedance ≥10% during RDN ("successful" procedure), but almost zero otherwise: −19.9 [95% CI: −13.7; −24.5] vs −0.5 [95% CI: −11.9; 12.9] mmHg, respectively (raw estimates), p=0.003. The difference in BP lowering was less pronounced and non-significant when the procedural "success" was defined according to the average maximal electrode temperature. Conclusions: The impedance decrease during radiofrequency RDN treatment may be an effective criterion of the procedural success of the intervention. Guiding radiofrequency RDN by the impedance drop 10% or greater may significantly improve the efficacy of the procedure. Funding Acknowledgement: Type of funding source: None