The effect of renal denervation on resistant hypertension: Meta-analysis of randomized controlled clinical trials

Controversies in Hypertension IV: Renal Denervation

Renal denervation is not a cure for hypertension. Although more recent sham-controlled trials were positive, a significant minority of patients in each trial were unresponsive. The optimal patient or patients need to be defined. Combined systolic/diastolic hypertension appears more responsive than isolated systolic hypertension. It remains uncertain whether patients with comorbidities associated with higher adrenergic tone should be targeted, including obesity, diabetes, sleep apnea, and chronic kidney disease. No biomarker can adequately predict response. A key to a successful response is the adequacy of denervation, which currently cannot be assessed in real time. It is uncertain what is the optimal denervation methodology: radiofrequency, ultrasound, or ethanol injection. Radiofrequency requires targeting the distal main renal artery plus major branches and accessory arteries. Although denervation appears to be safe, conclusive data on quality of life, improved target organ damage, and reduced cardiovascular events/mortality are required before denervation can be generally recommended.

Renal denervation in the antihypertensive arsenal - knowns and known unknowns

Even though it has been more than a decade since renal denervation (RDN) was first used to treat hypertension and an intense effort on researching this therapy has been made, it is still not clear how RDN fits into the antihypertensive arsenal. There is no question that RDN lowers blood pressure (BP), it does so to an extent at best corresponding to one antihypertensive drug. The procedure has an excellent safety record. However, it remains clinically impossible to predict whose BP responds to RDN and whose does not. Long-term efficacy data on BP reduction are still unconvincing despite the recent results in the SPYRAL HTN-ON MED trial; experimental studies indicate that reinnervation is occurring after RDN. Although BP is an acceptable surrogate endpoint, there is complete lack of outcome data with RDN. Clear indications for RDN are lacking although patients with resistant hypertension, those with documented increase in activity of the sympathetic system and perhaps those who desire to take fewest medication may be considered.

Renal Denervation for Uncontrolled and Resistant Hypertension: Systematic Review and Network Meta-Analysis of Randomized Trials

Comparative efficacy and safety of renal denervation (RDN) interventions for uncontrolled (UH) and resistant hypertension (RH) is unknown. We assessed the comparative efficacy and safety of existing RDN interventions for UH and RH. Six search engines were searched up to 1 May 2020. Primary outcomes were mean 24-h ambulatory and office systolic blood pressure (SBP). Secondary outcomes were mean 24-h ambulatory and office diastolic blood pressure (DBP), clinical outcomes, and serious adverse events. Frequentist random-effects network meta-analyses were used to evaluate effects of RDN interventions. Twenty randomized controlled trials (RCTs) (n = 2152) were included, 15 in RH (n = 1544) and five in UH (n = 608). Intervention arms included radiofrequency (RF) in main renal artery (MRA) (n = 10), RF in MRA and branches (n = 4), RF in MRA+ antihypertensive therapy (AHT) (n = 5), ultrasound (US) in MRA (n = 3), sham (n = 8), and AHT (n = 9). RF in MRA and branches ranked as the best treatment to reduce 24-h ambulatory, daytime, and nighttime SBP and DBP versus other interventions (p-scores: 0.83 to 0.97); significant blood pressure effects were found versus sham or AHT. RF in MRA+AHT was the best treatment to reduce office SBP and DBP (p-scores: 0.84 and 0.90, respectively). RF in MRA and branches was the most efficacious versus other interventions to reduce 24-h ambulatory SBP and DBP in UH or RH.

Sham-Controlled Randomized Trials of Catheter-Based Renal Denervation in Patients With Hypertension

BACKGROUND

There are conflicting data regarding the relative effectiveness of renal sympathetic denervation (RSD) in patients with hypertension.

OBJECTIVES

The purpose of this study was to evaluate the blood pressure (BP) response after RSD in sham-controlled randomized trials.

METHODS

Databases were searched through June 30, 2018. Randomized trials (RCTs) with ≥50 patients comparing catheter-based RSD with a sham control were included. The authors calculated summary treatment estimates as weighted mean differences (WMD) with 95% confidence intervals (CIs) using random-effects meta-analysis.

RESULTS

The analysis included 977 patients from 6 trials. The reduction in 24-h ambulatory systolic blood pressure (ASBP) was significantly greater for patients treated with RSD than sham procedure (WMD -3.65 mm Hg, 95% CI: -5.33 to -1.98; p < 0.001). Compared with sham, RSD was also associated with a significant decrease in daytime ASBP (WMD -4.07 mm Hg, 95% CI: -6.46 to -1.68; p < 0.001), office systolic BP (WMD -5.53 mm Hg, 95% CI: -8.18 to -2.87; p < 0.001), 24-h ambulatory diastolic BP (WMD -1.71 mm Hg, 95% CI: -3.06 to -0.35; p = 0.01), daytime ambulatory diastolic BP (WMD -1.57 mm Hg, 95% CI: -2.73 to -0.42; p = 0.008), and office diastolic BP (WMD -3.37 mm Hg, 95% CI: -4.86 to -1.88; p < 0.001). Compared with first-generation trials, a significantly greater reduction in daytime ASBP was observed with RSD in second-generation trials (6.12 mm Hg vs. 2.14 mm Hg; p interaction = 0.04); however, this interaction was not significant for 24-h ASBP (4.85 mm Hg vs. 2.23 mm Hg; p interaction = 0.13).

CONCLUSIONS

RSD significantly reduced blood pressure compared with sham control. Results of this meta-analysis should inform the design of larger, pivotal trials to evaluate the long-term efficacy and safety of RSD in patients with hypertension.

Baroreflex activation therapy: a new approach to the management of advanced heart failure with reduced ejection fraction

Chronic heart failure is a common clinical condition characterized by persistent excessive sympathetic nervous system activation. The derangement of the sympathetic activity has relevant implications for disease progression and patient survival. Aiming to positively impact patient outcome, autonomic nervous system modulatory therapies have been developed and tested in animal and clinical studies. As a general gross assumption, direct vagal stimulation and baroreflex activation are considered equivalent. This assumption does not take into account the fact that direct cervical vagal nerve stimulation involves activation of both afferent and efferent fibers innervating not only the heart, but the entire visceral system, leading to undesired responses to and from this compartment. The different action of baroreflex activation is based on generating a centrally mediated reduction of sympathetic outflow and increasing parasympathetic activity to the heart via a physiological reflex pathway. Thus, baroreflex activation rebalances the unbalanced autonomic nervous system via a specific path. Independent and complementary investigations have shown that sympathetic nerve activity can be rebalanced via control of the arterial baroreflex in heart failure patients.

Results from recent pioneering research studies support the hypothesis that baroreflex activation can add significant therapeutic benefit on top of guideline-directed medical therapy in patients with advanced heart failure. In the present review, baroreflex activation therapy results are discussed, focusing on critical aspects like patient selection rationale to support clinician orientation in opting for baroreflex activation therapy when, on top of current guideline-directed medical treatment, other therapies are to be considered.

Long noncoding RNA CCAT2 can predict metastasis and a poor prognosis: A meta-analysis

BACKGROUND

Colon cancer associated transcript 2 (CCAT2), a novel long non-coding RNA (lncRNA), plays a key role in tumorigenesis. This meta-analysis systematically summarizes the relationship between CCAT2 and cancers.

METHODS

A comprehensive, computerized literature search was conducted in PubMed, Cochrane library, Chinese National Knowledge Infrastructure, and Chinese Wan Fang database. Odds ratios (ORs), hazard ratios (HRs) and their 95% confidence interval (95% CI) were calculated to assess the effect size. A total of 9 studies were enrolled in this meta-analysis, which was performed by Revman5.3 software and Stata12.0.

RESULTS

Our meta-analysis indicates that patients with elevated expression of CCAT2 are prone to developing distant metastasis (DM) (OR=12.42; 95% CI=5.77-26.74; P < 0.00001), which is associated with a tendency for lymph nodes metastasis (LNM) (OR=3.60 95% CI=1.65-7.87, P=0.001). Further analyses reveal that patients with high CCAT2 expression have poorer overall survival (OS) (HR=1.53, 95% CI=1.15-2.02, P=0.003, random-effects) and progression-free survival (PFS) (HR=2.88, 95% CI=1.81-4.56, P < 0.00001, fixed-effects).

CONCLUSIONS

Therefore, CCAT2 may be a potential novel biomarker for indicating clinical outcomes of human cancers.