Effects of percutaneous renal sympathetic denervation on cardiac function and exercise tolerance in patients with chronic heart failure

Effects of renal denervation on the incidence and severity of cardiovascular diseases

Renal denervation (RDN) is a neuromodulation therapy performed in patients with hypertension using an intraarterial catheter. Recent randomized sham-controlled trials have shown that RDN has significant antihypertensive effects that last for more than 3 years. Based on this evidence, the US Food and Drug Administration has approved two devices, the ultrasound-based ReCor ParadiseTM RDN system and the radiofrequency-based Medtronic Symplicity SpyralTM RDN system, as adjunctive therapy for patients with refractory and uncontrolled hypertension. On the other hand, there have been no randomized sham-controlled prospective outcome trials on RDN, and the effects of RDN on cardiovascular events such as myocardial infarction, heart failure, and stroke have not been elucidated. This mini-review summarizes the latest findings focusing on the effects of RDN on organ protection and physiological function and symptoms in both preclinical and clinical studies. Furthermore, the feasibility of using blood pressure as surrogate marker for cardiovascular outcomes is discussed in the context of relevant clinical studies on RDN. A comprehensive understanding of the beneficial effects of RDN on the incidence and severity of cardiovascular diseases with their underlying mechanisms will enhance physicians' ability to incorporate RDN into clinical strategies to prevent cardiovascular events including myocardial infarction, heart failure, and stroke. This mini-review focuses on the effects of RDN on organ protection and physiological function and symptoms in preclinical and clinical studies. RDN is expected to reduce the onset and progression of cardiovascular diseases including myocardial infarction, heart failure, and stroke in clinical practice. LV left ventricular, LVEF left ventricular ejection fraction, VO2max maximal oxygen uptake, VT ventricular tachycardia, VF ventricular fibrillation, 6MWD 6-min walk distance, NT-proBNP N-terminal pro-B-type natriuretic peptide, NYHA New York Heart Association, BBB blood-brain barrier, BP blood pressure.

A kidney-brain neural circuit drives progressive kidney damage and heart failure

Chronic kidney disease (CKD) and heart failure (HF) are highly prevalent, aggravate each other, and account for substantial mortality. However, the mechanisms underlying cardiorenal interaction and the role of kidney afferent nerves and their precise central pathway remain limited. Here, we combined virus tracing techniques with optogenetic techniques to map a polysynaptic central pathway linking kidney afferent nerves to subfornical organ (SFO) and thereby to paraventricular nucleus (PVN) and rostral ventrolateral medulla that modulates sympathetic outflow. This kidney-brain neural circuit was overactivated in mouse models of CKD or HF and subsequently enhanced the sympathetic discharge to both the kidney and the heart in each model. Interruption of the pathway by kidney deafferentation, selective deletion of angiotensin II type 1a receptor (AT1a) in SFO, or optogenetic silence of the kidney-SFO or SFO-PVN projection decreased the sympathetic discharge and lessened structural damage and dysfunction of both kidney and heart in models of CKD and HF. Thus, kidney afferent nerves activate a kidney-brain neural circuit in CKD and HF that drives the sympathetic nervous system to accelerate disease progression in both organs. These results demonstrate the crucial role of kidney afferent nerves and their central connections in engaging cardiorenal interactions under both physiological and disease conditions. This suggests novel therapies for CKD or HF targeting this kidney-brain neural circuit.

Renal denervation in management of heart failure with reduced ejection fraction: A systematic review and meta-analysis

BACKGROUND

Some, but not all, recent studies have shown that renal denervation (RDN) can improve cardiac function and exercise tolerance in people who have heart failure with reduced ejection fraction (HFrEF). This study assessed the efficacy and safety of RDN as a treatment for HFrEF.

METHODS

The Medline, Cochrane Library, Embase, and PubMed databases were searched through to September 28, 2022 for clinical studies that evaluated the effect of RDN on HFrEF. The primary endpoints were changes in left ventricular ejection fraction (LVEF) and 6-min walk distance (6MWD). Secondary endpoints were changes in echocardiographic parameters, including left ventricular end-diastolic and end-systolic diameters, left atrial diameter, and interventricular septal thickness. N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels, New York Heart Association (NYHA) class, heart rate, and systolic and diastolic blood pressure were also evaluated. Major adverse events were defined as death and rehospitalization for heart failure during follow-up. The estimated glomerular filtration rate (eGFR) and serum creatinine level were extracted as measures of renal function.

RESULTS

Eleven trials comprising 313 patients were eligible for quantitative analysis. Pooled analyses showed a mean increase in LVEF of 4.25 % (95 % CI 1.77-6.72; p < 0.001, I² = 69 %) and an increase in 6MWD (mean difference 50.28 m, 95 % CI 8.78-91.78; p = 0.02; I² = 81 %) after RDN. Left ventricular end-diastolic and end-systolic diameters, left atrial diameter, and interventricular septal thickness also improved after RDN. NT-proBNP, NYHA class, and heart rate were significantly decreased after RDN. There were no significant changes in blood pressure after RDN. Mortality and HF-related hospitalization rates were relatively low. There was no significant change in eGFR or creatinine after RDN.

CONCLUSIONS

Our findings suggest that RDN can effectively increase LVEF and 6MWD in patients with HFrEF but require confirmation in studies with larger sample sizes and longer follow-up durations.

Effects of renal denervation therapy on cardiac function and malignant arrhythmia in patients with reduced left ventricular ejection fraction and narrow QRS complexes treated with implantable cardioverter defibrillator

Objective : The purpose of this study was to explore the effects of renal denervation (RDN) on cardiac function and malignant arrhythmia in patients with reduced left ventricular ejection fraction (HFrEF) and narrow QRS treated with an implantable cardioverter defibrillator (ICD). Methods: A total of 20 eligible HFrEF patients [left ventricular ejection fraction (LVEF) <40%] and narrow QRS complexes (QRS duration <120 ms) were randomized into either the ICD plus RDN group or the ICD only group during 17 April 2014 to 22 November 2016. Clinical data, including clinical characteristics, blood biochemistry, B-type natriuretic peptide, echocardiographic indexes, 6-min walk distance (6MWD), New York Heart Association (NYHA) classification, and count of ICD discharge events before and after the operation were analyzed. Patients were followed up for up to 3 years post ICD or ICD plus RDN. Results: Baseline clinical data were comparable between the two groups. Higher LVEF (%) (mixed model repeated measure, p = 0.0306) (39.50% ± 9.63% vs. 31.20% ± 4.52% at 1 year; 41.57% ± 9.62% vs. 31.40% ± 8.14% at 3 years), systolic blood pressure (p = 0.0356), and longer 6MWD (p < 0.0001) as well as reduction of NYHA classification (p < 0.0001) were evidenced in the ICD plus RDN group compared to ICD only group during follow-up. Patients in the ICD plus RDN group experienced fewer ICD discharge events (2 vs. 40) and decreased diuretic use; rehospitalization rate (30% vs. 100%, p = 0.0031) and cardiogenic mortality rate (0% vs. 50%, p = 0.0325) were also significantly lower in the ICD plus RDN group than in the ICD only group during follow-up. Conclusion: ICD implantation plus RDN could significantly improve cardiac function and cardiac outcome as well as increase exercise capacity compared to ICD only for HFrEF patients with narrow QRS complexes.

The Potential Role of Renal Denervation in the Management of Heart Failure

Sympathetic nervous system activation in patients with heart failure is one of the main pathophysiologic mechanisms associated with the worse outcomes. Pharmacotherapies targeting neurohormonal activation have been at the center of heart failure management. Despite the advancement of therapies and the available treatments, heart failure continues to have an overall poor prognosis. Renal denervation was originally developed to lower systemic blood pressure in patients with poorly controlled hypertension, by modulating sympathetic outflow. However, more recently, multiple studies have investigated the effect of renal denervation in heart failure patients with both preserved (HFpEF) and reduced ejection fractions (HFrEF). This paper provides an overview of the potential effect of renal denervation in altering the various pathophysiologic, sympathetically mediated pathways that contribute to heart failure, and reviews the literature that supports its future use in those patients.

A Japan nationwide web-based survey of patient preference for renal denervation for hypertension treatment

Renal denervation is a potential alternative to antihypertensive drug therapy. However, data on patient preference for this treatment option are limited and there are no data specifically from Asian patients. This study evaluated patient preference for renal denervation in patients with hypertension from Japan. Patients were a subset of those who participated in a March 2020 online electronic survey of patients with hypertension who had regularly visited medical institutions for treatment, were receiving antihypertensive drug therapy and had home blood pressure recordings available. The survey included a question about patient preference for treatment with renal denervation. A total of 2,392 patients were included (66% male, mean age 59.8 ± 11.6 years, mean duration of hypertension 11.4 ± 9.5 years). Preference for renal denervation was expressed by 755 patients (31.6%), and was higher in males than in females, in younger compared with older patients, in those with higher versus lower blood pressure, in patients who were less adherent versus more adherent to antihypertensive drug therapy, and in those who did rather than did not have antihypertensive drug-related side effects. Significant predictors of preference for renal denervation on logistic regression analysis were younger patient age, male sex, higher home or office systolic blood pressure, poor antihypertensive drug adherence, the presence of heart failure, and the presence of side effects during treatment with antihypertensive drugs. Overall, a relevant proportion of Japanese patients with hypertension expressed a preference for renal denervation. This should be taken into account when making shared decisions about antihypertensive drug therapy.

Safety and efficacy of renal denervation in patients with heart failure with reduced ejection fraction (HFrEF): A systematic review and meta-analysis

INTRODUCTION

A systematic analysis of clinical trials was performed in order to assess the effectiveness and risks of bilateral renal denervation (RDN) in patients with chronic heart failure with reduced ejection fraction (HFrEF).

METHODS

A systematic review was conducted of all clinical trials exploring the effectiveness of RDN in patients with HF who had reduced (<50%) EF. Primary outcomes were NYHA class, 6-min walk test, N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels, left ventricular ejection fraction (LVEF) and other cardiac parameters including left ventricular end-systolic diameter (LVESD), left ventricular end-diastolic diameter (LVEDD), and left atrium diameter (LAD). Secondary outcomes were systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), glomerular filtration rate (GFR), and creatinine.

RESULTS

Seven studies were included in this analysis. From baseline to 6 months after RDN, the pooled mean NYHA class was decreased (mean difference [MD], -0.9; 95% confidence interval [CI], -1.6 to -0.2; P = 0.018), the mean 6-min walk test was increased (MD, 79.5 m; 95% CI, 26.9 to 132.1; P = 0.003), and the average NT-proBNP level was decreased (MD, -520.6 pg/mL; 95% CI, -1128.4 to 87.2; P = 0.093). Bilateral RDN increased the LVEF (MD, 5.7%; 95% CI, 1.6 to 9.6; P = 0.004), decreased the LVESD (MD, -0.4 cm; 95% CI, -0.5 to -0.2; P < 0.001), decreased the LVEDD (MD, -0.5 cm; 95% CI, -0.6 to -0.3; P < 0.001), and decreased the LAD (MD, -0.4 cm; 95% CI, -0.8 to 0; P = 0.045). In addition, RDN significantly decreased systolic BP (MD, -9.4 mmHg; 95% CI, -16.3 to -2.4; P = 0.008) and diastolic BP (MD, -4.9 mmHg; 95% CI, -9.5 to -0.4; P = 0.033), and decreased HR (MD, -4.5 bpm; 95% CI, -8.2to -0.9; P = 0.015). RDN did not significantly change GFR (MD, 7.9; 95% CI, -5.0 to 20.8; P = 0.230), or serum creatinine levels (MD, -7.2; 95% CI, -23.7 to 9.4; P = 0.397).

CONCLUSION

Bilateral RDN appears safe and well-tolerated in patients with HF. RDN improved the signs and symptoms of HF and slightly decreased systolic and diastolic BP without affecting renal function in the clinical trials performed to date.

Comparison of a 5 F Microtube-Irrigated Ablation Catheter and a General Ablation Catheter in the Treatment of Resistant Hypertension with Renal Denervation

Objective: To assess the effectiveness of catheter-based renal denervation for reducing blood pressure in patients with resistant hypertension using a 5 F microtube-irrigated ablation catheter.Methods: Sixty patients with resistant hypertension were divided into two groups: a microtube-irrigated ablation catheter group and a general ablation catheter group. We conducted 12-month follow-up of all patients and recorded clinical blood pressure, ambulatory blood pressure, medication use, and biochemistry test results in both groups at the baseline and at the 12-month follow-up.Results: All patients underwent renal denervation. At the 6-month follow-up, ambulatory blood pressure in the microtube-irrigated ablation catheter group was significantly lower than in the general ablation catheter group (systolic blood pressure 142.0 ± 14.4 mmHg vs. 150.8 ± 17.9 mmHg, P=0.04; diastolic blood pressure 81.2 ± 7.0 mmHg vs. 87.6 ± 8.0 mmHg, P=0.002). At the 12-month follow-up, the between-group difference in ambulatory blood pressure was not statistically significant. At the 12-month follow-up, the number of antihypertensive drugs and diuretics used in the microtube-irrigated ablation catheter group was less than in the general ablation catheter group (P=0.043). There was no statistical difference between the two groups in the results of biochemistry tests and echocardiography.Conclusion: The microtube-irrigated ablation catheter is more effective in treating hypertension than the general ablation catheter at the 6-month follow up and thus fewer antihypertensive drugs were used in the microtube-irrigated ablation catheter group than in the general ablation catheter group.

Immediate Renal Denervation After Acute Myocardial Infarction Mitigates the Progression of Heart Failure via the Modulation of IL-33/ST2 Signaling

Objective: Previous studies have demonstrated the protective effects of renal denervation (RDN) in pre-existing heart failure, but the effects of immediate RDN after acute myocardial infarction (AMI) on subsequent cardiac remodeling have not been reported. This study aimed to investigate the cardioprotective effects of immediate RDN after AMI and its underlying mechanism.

Methods: AMI was induced by intracoronary gelatin sponge embolization in 14 Shanghai white pigs that were randomized to undergo either renal angiography (AMI+sham group) or RDN (AMI+RDN group) after 1 h of hemodynamic monitoring. Cardiac function of the two groups was measured at baseline, 1 h post-AMI and at the 1 month follow-up (1M-FU) by transthoracic echocardiography (TTE). Plasma NT-proBNP, soluble ST2 (sST2), norepinephrine (NE), and renin-angiotensin-aldosterone system activity were detected simultaneously. The renal cortex was harvested for NE measurement after the 1M-FU, and the renal arteries were stained with tyrosine hydroxylase for the evaluation of sympathetic activity. Heart tissues in the non-ischemic areas were collected to assess histological and molecular left ventricular (LV) remodeling by pathological staining, RT-PCR, and western blotting.

Results: There was no difference in the hemodynamic stability or cardiac function between the two groups at baseline and 1 h post-AMI. Six pigs from each of the two groups completed the 1M-FU. TTE analysis revealed the improved cardiac function of immediate RDN in the AMI+RDN group and circulating NT-proBNP levels were lower than those in the AMI+sham group. Further analysis showed significantly less interstitial fibrosis in the remote non-ischemic myocardium after immediate RDN, together with decreased cardiomyocyte hypertrophy and inflammatory cell infiltration. sST2 levels in circulating and myocardial tissues of animals in the AMI+RDN group were significantly higher than those in the AMI+sham group, accompanied by corresponding alterations in IL-33/ST2 and downstream signaling.

Conclusions: Immediate RDN can improve cardiac function and myocardial remodeling after AMI via modulation of IL-33/ST2 and downstream signaling.

Renal, Cardiac, and Autonomic Effects of Catheter-Based Renal Denervation in Ovine Heart Failure

[Figure: see text].

Nocturnal Hypertension and Heart Failure: Mechanisms, Evidence, and New Treatments

Heart failure (HF) is a common condition with an increasing prevalence. Despite a variety of evidence-based treatments for patients with HF with reduced ejection fraction, morbidity and mortality rates remain high. Furthermore, there are currently no treatments that have yet been shown to reduce complication and death rates in patients who have HF with preserved ejection fraction. Hypertension is a common comorbidity in patients with HF, contributing to disease development and prognosis. For example, hypertension is closely associated with the development of left ventricular hypertrophy, which an important precursor of HF. In particular, nighttime blood pressure (BP) appears to be an important, modifiable risk factor. Both nighttime BP and an abnormal circadian pattern of nighttime BP dipping have been shown to predict development of HF and the occurrence of cardiovascular events, independent of office BP. Key mechanisms for this association include sodium handling/salt sensitivity and increased sympathetic activation. These pathogenic mechanisms are targeted by several new treatment options, including sodium-glucose cotransporter 2 inhibitors, angiotensin receptor neprilysin inhibitors, mineralocorticoid receptor antagonists, and renal denervation. All of these could form part of antihypertensive strategies designed to control nighttime BP and contribute to the goal of achieving perfect 24-hour BP management. Nevertheless, additional research is needed to determine the effects of reducing nighttime BP and improving the circadian BP profile on the rate of HF, other cardiovascular events, and mortality.

Effects of catheter-based renal denervation on heart failure with reduced ejection fraction: a meta-analysis of randomized controlled trials

Despite the major progress in the treatment of heart failure, the burden of heart failure is steadily increasing in the Western world. Heart failure is characterized by increased sympathetic activity, and chronic sympathetic activation is involved in the maintenance of the pathological state. Recent studies have shown that catheter-based renal denervation (RDN) presents a safe and minimally invasive treatment option for uncontrolled hypertension, a condition that is driven by increased sympathetic activity. Although randomized controlled trials (RCTs) have examined the effect of RDN in heart failure patients, results are inconsistent due partly to limited power with small sample sizes. We aimed to conduct a meta-analysis of RCTs on the effect of RDN in heart failure patients with reduced left ventricular (LV) ejection fraction (EF). Electronic search identified 5 RCTs including 177 patients. In the pooled analysis, RDN increased LVEF (weighted mean difference (WMD) [95% CI] = 6.289 [1.883, 10.695]%) and 6-min walk distance (61.063 [24.313, 97.813] m) and decreased B-type natriuretic peptide levels (standardized mean difference [95% CI] = - 1.139 [- 1.824, - 0.454]) compared with control. In contrast, RDN did not significantly change estimated glomerular filtration rate (WMD [95% CI] = 5.969 [- 2.595, 14.533] ml/min/1.73 m²) and systolic (- 1.991 [- 15.639, 11.655] mmHg) or diastolic (- 0.003 [- 10.325, 10.320] mmHg) blood pressure compared with control. Our meta-analysis suggests that RDN may improve LV function and exercise capacity in heart failure patients with reduced EF, providing the rationale to conduct large-scale multicenter trials to confirm the observed potential benefits of RDN.

Renal denervation in patients with symptomatic chronic heart failure despite resynchronization therapy - a pilot study

Introduction

Renal denervation (RD) has been shown to decrease sympathetic function in patients with hypertension. Its efficacy in symptomatic chronic heart failure (CHF) patients not responding to cardiac resynchronization therapy (CRT) has not been evaluated.

Aim

To assess whether a less invasive treatment method – renal denervation – is safe in symptomatic heart failure patients despite optimal medical treatment and resynchronization therapy and whether it is associated with an improvement in clinical status, exercise capacity and hemodynamic parameters.

Material and methods

The study was an open-label, randomized, controlled clinical trial. Patients were divided into an intervention (RD) and a control group. Clinical data collection, blood pressure (BP) measurements, echocardiography, 6-minute walk test (6MWT) and laboratory tests were performed before, 6 and 12 months after RD. The patients were followed-up to 24 months.

Results

We included 20 patients aged 52.0 to 86.0 years (median age: 71.5 years), 15 males and 5 females with median left ventricular ejection fraction (LVEF) of 32.5%, body mass index 31.3 kg/m². Renal denervation was safe, no significant adverse effects were registered. There were no significant differences in LVEF, BP, 6MWT and N-terminal prohormone of brain natriuretic peptide (NT-proBNP) concentration 6 and 12 months after RD or control.

Conclusions

Our results indicate that RD in CHF patients not responding to CRT is safe and does not worsen exercise capacity and hemodynamic parameters.

Effects of catheter-based renal denervation on heart failure with reduced ejection fraction: a systematic review and meta-analysis

Despite the recent advances in the management of heart failure, the mortality of heart failure patients remains high. It is of urgent need to develop new therapy for heart failure. Heart failure is characterized by increased sympathetic activity, and chronic sympathetic activation is involved in the maintenance of the pathological state. Catheter-based renal denervation (RDN) has emerged as an invasive but safe approach that can reduce sympathetic activation. Studies have reported inconsistent results regarding the effect of RDN in heart failure patients due to limited power with small sample sizes. We aimed to conduct a meta-analysis of the effect of RDN on heart failure patients with reduced left ventricular (LV) ejection fraction (EF). An electronic search for studies examining the effect of RDN on LV function in heart failure patients with reduced EF was conducted. Two controlled (80 patients) and 2 uncontrolled studies (21 patients) were included in this meta-analysis. In the pooled analysis, 6 months after RDN, there was a greater increase in EF (weighted mean difference [95% CI] = 8.63 [6.02, 11.24] %) and a greater decrease in LV end-diastolic diameter (-0.58 [-0.83, -0.34] cm) in RDN group than in control group. No serious adverse events such as acute renal artery stenosis and dissection occurred. Our meta-analysis of feasibility studies suggests that RDN may improve LV function in heart failure patients with reduced EF, providing the rationale to conduct next phase trials to confirm the observed potential benefits of RDN.

Renal denervation improves cardiac function by attenuating myocardiocyte apoptosis in dogs after myocardial infarction

Background

Myocardial apoptosis is important in the pathogenesis and progression of myocardial infarction-induced heart failure (MI-HF). Renal sympathetic denervation (RDN) has become a promising therapeutic strategy for the treatment of HF. Previous studies have shown that RDN could improve heart function Yao et al. (Exp Ther Med 14:4104-4110, 2017). However, whether and how RDN regulates myocardial apoptosis in MI-HF is unclear. This study sought to evaluate the effects of RDN on cardiac function and apoptosis-related gene expression in MI-HF dogs.

Methods

Eighteen healthy mongrel dogs were randomly divided into control group(n = 6), model group(n = 6) and treatment group(n = 6). MI-HF was established in model group and treatment group by anhydrous alcohol embolization, after heart failure dogs in the treatment group and model group proceeded bilateral renal artery ablation and bilateral renal arteriography, respectively. The cardiac function parameters were evaluated by echocardiographic; the serum NT-BNP level was detected by ELISA; the degree of myocardial fibrosis was observed through masson staining; the expression of MMP-2, MMP-9 in the cardiac were got by immunohistochemistry. TUNEL method was used to observe cardiomyocyte apoptotsis and calculate the apoptosis index (AI). Relative expression of Bcl-2 and Bax, Caspase3 and GRP78 were detected using RT-PCR and Western Blot. Renal artery H&E staining and serum creatinine were conducted to access the efficacy and safety of RDN.

Results

Four weeks after RDN, the LVEDD, LVESD and LVEDP decreased, and the LVEF and LVSP increased in the treatment group compared with those in the control group (all P < 0.05). Moreover, NT-BNP, an indicator of cardiac function was decreased. Additionally, MMP-2 and MMP-9 levels in the myocardium decreased significantly in the treatment group. Furthermore, the levels of Bax, and caspase 3 decreased, while the level of Bcl-2 increased. Thus, myocardial apoptosis was attenuated in RDN treated dogs. We also found that the level of GRP78 which is activated in response to endoplasmic reticulum (ER) stress, was decreased. However, serum creatinine levels were not significantly different between the RND-treated dogs and the control dogs.

Conclusion

Cardiac function was improved by RDN treatment through regulating apoptosis and ER stress in cardiomyocytes in dogs after MI.