Predictors of Renal Denervation Efficacy in the Treatment of Resistant Hypertension.

UNLABELLED: The aims of the study were to evaluate the effects of renal sympathetic denervation (RSD) on the heart and to identify the predictors of RSD efficacy in patients with resistant arterial hypertension. The study comprised 60 RSD patients (54.6 ± 9.5 years) who received full-dose antihypertensive therapy (4.1 drugs) including diuretics. Initially, 58.6% of patients had abnormal left ventricular (LV) diastolic function. All patients received echocardiography before and 24 weeks after RSD. Renal sympathetic denervation was achieved through the endovascular radiofrequency ablation (RFA) of the renal arteries. Drug therapy continued for the entire period of observation. After RSD, all patients were retrospectively assigned to two groups: group 1 comprised patients (n = 22; 36.7%) in whom the myocardial mass (MM) of the left ventricle decreased by more than 10 g after RSD; group 2 comprised patients (n = 38; 63.3%) in whom LV MM increased or decreased by less than 10 g. Anthropometry, arterial blood pressure, heart rate, therapy, and LV end-diastolic dimensions (EDD) were comparable in these groups. After RSD, the values of office blood pressure significantly decreased and MM regressed by more than 10 g in 36.7% of patients; LV diastolic function normalized in 31% of patients, and diastolic dysfunction improved in 14% of patients. The study found the associations between the initial LV wall dimensions and LV MM changes. Unlike LV EDD, arterial blood pressure, or heart rate, the initial values of LV wall thickness predicted LV MM regress. TRIAL REGISTRATION: #NCT01499810 https://clinicaltrials.gov/ct2/show/NCT01499810.

Denervation of the distal renal arterial branches vs. conventional main renal artery treatment: a randomized controlled trial for treatment of resistant hypertension.

BACKGROUND: Effective treatment of uncontrolled hypertension using catheter-based percutaneous renal denervation may depend strongly on the anatomic strategy applied when delivering therapy. We hypothesized that concentering renal denervation treatment in the distal region of the artery would improve clinical response. METHODS AND RESULTS: We conducted a single-center, double-blind, randomized, controlled, and parallel group study (ClinicalTrials.gov NCT02667912). Fifty-one treatment-resistant hypertensive patients meeting guideline indications were randomized either to 'conventional' treatment restricted to the main renal artery (n = 26) or to 'distal' treatment applied mainly in the distal branches beyond the main bifurcation (n = 25). Computer-based treatment assignment was performed in the catheterization laboratory at the time of the procedure by the interventional radiologist and remained unknown to patients, investigators, and other outcomes assessors for the entire study period. Six months after randomization, the distal therapy group (n = 24) had a significantly greater decrease in the primary outcome, 24-h mean ambulatory SBP, as compared with the conventionally treated group (n = 21): -22.6 ±â€Š20.0 vs -9.4 ±â€Š18.7 mmHg; P less than 0.05. No major safety issues were observed in either group. CONCLUSION: Percutaneous renal denervation treatment was significantly less effective at lowering 24-h blood pressure in treatment-resistant hypertensive patients when therapy was applied conventionally in the trunk of renal artery as compared with when applied to distal segmental branches. This observation is in accordance with previous surgical and anatomical findings showing that most renal nerve fibers are distant from the lumen proximally and become available for endovascular treatment mainly in the distal portion of the vessel.

Improved automatic analysis of ambulatory blood pressure data based on precise detection of individual night-time from diurnal profile of heart rate.

BACKGROUND: Software programs sold with ambulatory blood pressure monitoring (ABPM) devices are designed to use some set 'typical' night-time (e.g. 2300-0700) to estimate daytime/night-time blood pressure (BP) with limited accuracy. Alternative use of individual periods of sleep/wakefulness from patient diaries is time consuming and subjective. We developed a simple mathematical algorithm for the detection of the 'night-time' as a period of low values in diurnal profiles of heart rate (HR) allowing accurate automatic analysis of daytime/night-time blood pressure. To test this technique we designed a software application allowing automatic analysis of ABPM data based on the different night-time definitions, including the developed algorithm and compared reproducibility of the degree of BP dipping produced by the different methods across two days of 48-h ABPM. METHODS: A 48-h ABPM study was performed in 33 patients with uncomplicated stage II hypertension. Means and standard deviations (SD) of the differences in the degree of BP dipping between two 24-h periods of 48-h ABPM were obtained separately for three methods of night-time definition: automatic detection from individual HR profiles, fixed 2300-0700 h interval and sleep time from patient diaries. RESULTS: Reproducibility of the BP dip estimation across 2 days of BP monitoring was significantly better for night-time detected from individual HR profiles than for the fixed 2300-0700 h interval or sleep time from diary. The SD of the differences was 6.7/8.2 compared with 13.5/18.3 and 13.0/14.8 respectively (systolic BP/diastolic BP, mmHg). CONCLUSIONS: Implementation of the developed method of night-time definition may significantly improve automatic analysis of ABPM data.