Surgical ablation of the right greater splanchnic nerve for the treatment of heart failure with preserved ejection fraction: first-in-human clinical trial

Interventional therapies for chronic heart failure: An overview of recent developments

Heart failure (HF), the final manifestation of most cardiovascular diseases, has become a major global health concern, affecting millions of individuals. Despite basic drug treatments, patients present with high morbidity and mortality rates. However, recent advancements in interventional therapy have shown promising results in improving the prognosis of patients with HF. These advancements include transcatheter aortic valve replacement for severe aortic stenosis, transcatheter mitral valve repair for chronic mitral regurgitation, neuromodulation therapy for multiple targets and measures in the treatment of chronic HF and left ventricular assist device implantation for advanced HF (Figure 1). In this review, we aimed to provide an overview of the current progress in interventional therapies for chronic HF.

The sympathetic nervous system in heart failure with preserved ejection fraction

The sympathetic nervous system (SNS) is a major mediator of cardiovascular physiology during exercise in healthy people. However, its role in heart failure with preserved ejection fraction (HFpEF), where exercise intolerance is a cardinal symptom, has remained relatively unexplored. The present review summarizes and critically explores the currently limited data on SNS changes in HFpEF patients with a particular emphasis on caveats of the data and the implications for its subsequent interpretation. While direct measurements of SNS activity in HFpEF patients is scarce, modest increases in resting levels of muscle sympathetic nerve activity are apparent, although this may be due to the co-morbidities associated with the syndrome rather than HFpEF per se. In addition, despite some evidence for dysfunctional sympathetic signaling in the heart, there is no clear evidence for elevated cardiac sympathetic nerve activity. The lack of a compelling prognostic benefit with use of β-blockers in HFpEF patients also suggests a lack of sympathetic hyperactivity to the heart. Similarly, while renal and splanchnic denervation studies have been performed in HFpEF patients, there is no concrete evidence that the sympathetic nerves innervating these organs exhibit heightened activity. Taken together, the totality of data suggests limited evidence for elevated sympathetic nerve activity in HFpEF and that any SNS perturbations that do occur are not universal to all HFpEF patients. Finally, how the SNS responds during exertion in HFpEF patients remains unknown and requires urgent investigation.

Device therapies for heart failure with reduced ejection fraction: a new era

Even with significant advancements in the treatment modalities for patients with heart failure (HF), the rates of morbidity and mortality associated with HF are still high. Various therapeutic interventions, including cardiac resynchronization therapy, Implantable Cardiovascular-Defibrillators, and left ventricular assist devices, are used for HF management. Currently, more research and developments are required to identify different treatment modalities to reduce hospitalization rates and improve the quality of life of patients with HF. In relation to this, various non-valvular catheter-based therapies have been recently developed for managing chronic HF. These devices target the pathophysiological processes involved in HF development including neurohumoral activation, congestion, and left ventricular remodeling. The present review article aimed to discuss the major transcatheter devices used in managing chronic HF. The rationale and current clinical developmental stages of these interventions will also be addressed in this review.

Interplay of the heart, spleen, and bone marrow in heart failure: the role of splenic extramedullary hematopoiesis

Improvements in therapies for heart failure with preserved ejection fraction (HFpEF) are crucial for improving patient outcomes and quality of life. Although HFpEF is the predominant heart failure type among older individuals, its prognosis is often poor owing to the lack of effective therapies. The roles of the spleen and bone marrow are often overlooked in the context of HFpEF. Recent studies suggest that the spleen and bone marrow could play key roles in HFpEF, especially in relation to inflammation and immune responses. The bone marrow can increase production of certain immune cells that can migrate to the heart and contribute to disease. The spleen can contribute to immune responses that either protect or exacerbate heart failure. Extramedullary hematopoiesis in the spleen could play a crucial role in HFpEF. Increased metabolic activity in the spleen, immune cell production and mobilization to the heart, and concomitant cytokine production may occur in heart failure. This leads to systemic chronic inflammation, along with an imbalance of immune cells (macrophages) in the heart, resulting in chronic inflammation and progressive fibrosis, potentially leading to decreased cardiac function. The bone marrow and spleen are involved in altered iron metabolism and anemia, which also contribute to HFpEF. This review presents the concept of an interplay between the heart, spleen, and bone marrow in the setting of HFpEF, with a particular focus on extramedullary hematopoiesis in the spleen. The aim of this review is to discern whether the spleen can serve as a new therapeutic target for HFpEF.

Pharmacologic, Surgical, and Device-Based Cardiac Neuromodulation

The cardiac autonomic nervous system plays a key role in maintaining normal cardiac physiology, and once disrupted, it worsens the cardiac disease states. Neuromodulation therapies have been emerging as new treatment options, and various techniques have been introduced to mitigate autonomic nervous imbalances to help cardiac patients with their disease conditions and symptoms. In this review article, we discuss various neuromodulation techniques used in clinical settings to treat cardiac diseases.

Endovascular Ablation of the Right Greater Splanchnic Nerve in Heart Failure With Preserved Ejection Fraction: Rationale, Design and Lead-in Phase Results of the REBALANCE-HF Trial

OBJECTIVE

Splanchnic vasoconstriction augments transfer of blood volume from the abdomen into the thorax, which may increase filling pressures and hemodynamic congestion in patients with noncompliant hearts. Therapeutic interruption of splanchnic nerve activity holds promise to reduce hemodynamic congestion in patients with heart failure with preserved ejection fraction (HFpEF). Here we describe (1) the rationale and design of the first sham-controlled, randomized clinical trial of splanchnic nerve ablation for HFpEF and (2) the 12-month results of the lead-in (open-label) trial's participants.

METHODS

REBALANCE-HF is a prospective, multicenter, randomized, double-blinded, sham-controlled clinical trial of endovascular, transcatheter, right-sided greater splanchnic nerve ablation for volume management (SAVM) in patients with HFpEF. The primary objectives are to evaluate the safety and efficacy of SAVM and identify responder characteristics to inform future studies. The trial consists of an open-label lead-in phase followed by the randomized, sham-controlled phase. The primary efficacy endpoint is the reduction in pulmonary capillary wedge pressure (PCWP) at 1-month follow-up compared to baseline during passive leg raise and 20W exercise. Secondary and exploratory endpoints include health status (Kansas City Cardiomyopathy Questionnaire), 6-minute walk test distance, New York Heart Association class, and NTproBNP levels at 3, 6 and 12 months. The primary safety endpoint is device- or procedure-related serious adverse events at the 1-month follow-up.

RESULTS

The lead-in phase of the study, which enrolled 26 patients with HFpEF who underwent SAVM, demonstrated favorable safety outcomes and reduction in exercise PCWP at 1 month post-procedure and improvements in all secondary endpoints at 6 and 12 months of follow-up. The randomized phase of the trial (n = 44 SAVM; n = 46 sham) has completed enrollment, and follow-up is ongoing.

CONCLUSION

REBALANCE-HF is the first sham-controlled randomized clinical trial of greater splanchnic nerve ablation in HFpEF. Initial 12-month open-label results are promising, and the results of the randomized portion of the trial will inform the design of a future pivotal clinical trial. SAVM may offer a promising therapeutic option for patients with HFpEF.

TRIAL REGISTRATION

NCT04592445.

Role of splanchnic circulation in the pathogenesis of heart failure: State-of-the-art review

A hallmark of heart failure (HF), whether it presents itself during rest or periods of physical exertion, is the excessive elevation of intracardiac filling pressures at rest or with exercise. Many mechanisms contribute to the elevated intracardiac filling pressures, and notably, the concept of volume redistribution has gained attention as a cause of the elevated intracardiac filling pressures in patients with HF, particularly HF with preserved ejection fraction, who often present without symptoms at rest, with shortness of breath and fatigue appearing only during exertion. This phenomenon suggests cardiopulmonary system non-compliance and inappropriate volume distribution between the stressed and unstressed blood volume components. A substantial proportion of the intravascular blood volume is in the splanchnic vascular compartment in the abdomen. Preclinical and clinical investigations support the critical role of the sympathetic nervous system in modulating the capacitance and compliance of the splanchnic vascular bed via modulation of the greater splanchnic nerve (GSN). The GSN activation by stressors such as exercise causes excessive splanchnic vasoconstriction, which may contribute to the decompensation of chronic HF via volume redistribution from the splanchnic vascular bed to the central compartment. Accordingly, for example, GSN ablation for volume management has been proposed as a potential therapeutic intervention to increase unstressed blood volume. Here we provide a comprehensive review of the role of splanchnic circulation in the pathogenesis of HF and potential novel treatment options for redistributing blood volume to improve symptoms and prognosis in patients with HF.

Early Renal Denervation Attenuates Cardiac Dysfunction in Heart Failure With Preserved Ejection Fraction

BACKGROUND

The renal sympathetic nervous system modulates systemic blood pressure, cardiac performance, and renal function. Pathological increases in renal sympathetic nerve activity contribute to the pathogenesis of heart failure with preserved ejection fraction (HFpEF). We investigated the effects of renal sympathetic denervation performed at early or late stages of HFpEF progression.

METHODS AND RESULTS

Male ZSF1 obese rats were subjected to radiofrequency renal denervation (RF-RDN) or sham procedure at either 8 weeks or 20 weeks of age and assessed for cardiovascular function, exercise capacity, and cardiorenal fibrosis. Renal norepinephrine and renal nerve tyrosine hydroxylase staining were performed to quantify denervation following RF-RDN. In addition, renal injury, oxidative stress, inflammation, and profibrotic biomarkers were evaluated to determine pathways associated with RDN. RF-RDN significantly reduced renal norepinephrine and tyrosine hydroxylase content in both study cohorts. RF-RDN therapy performed at 8 weeks of age attenuated cardiac dysfunction, reduced cardiorenal fibrosis, and improved endothelial-dependent vascular reactivity. These improvements were associated with reductions in renal injury markers, expression of renal NLR family pyrin domain containing 3/interleukin 1β, and expression of profibrotic mediators. RF-RDN failed to exert beneficial effects when administered in the 20-week-old HFpEF cohort.

CONCLUSIONS

Our data demonstrate that early RF-RDN therapy protects against HFpEF disease progression in part due to the attenuation of renal fibrosis and inflammation. In contrast, the renoprotective and left ventricular functional improvements were lost when RF-RDN was performed in later HFpEF progression. These results suggest that RDN may be a viable treatment option for HFpEF during the early stages of this systemic inflammatory disease.

Advances in device-based treatment of heart failure with preserved ejection fraction: evidence from clinical trials

Heart failure with preserved ejection fraction (HFpEF) is a group of clinical syndromes that exhibit a remarkably heterogeneous phenotype, characterized by symptoms and signs of heart failure, left ventricular diastolic dysfunction, elevated levels of natriuretic peptides, and an ejection fraction greater than or equal to 50%. With the aging of the population and the escalating prevalence of hypertension, obesity, and diabetes, the incidence of HFpEF is progressively rising. Drug therapy options for HFpEF are currently limited, and the associated high risk of cardiovascular mortality and heart failure rehospitalization significantly impact patients' quality of life and longevity while imposing a substantial economic burden on society. Recent research indicates that certain device-based therapies may serve as valuable adjuncts to drug therapy in patients with specific phenotypes of HFpEF, effectively improving symptoms and quality of life while reducing the risk of readmission for heart failure. These include inter-atrial shunt and greater splanchnic nerve ablation to reduce left ventricular filling pressure, implantable heart failure monitor to guide diuresis, left atrial pacing to correct interatrial dyssynchrony, cardiac contractility modulation to enhance cardiac calcium handling, as well as renal denervation, baroreflex activation therapy, and vagus nerve stimulation to restore the autonomic imbalance. In this review, we provide a comprehensive overview of the mechanisms and clinical evidence pertaining to these devices, with the aim of enhancing therapeutic strategies for HFpEF.

Emerging devices for heart failure management

There have been significant advances in the treatment of heart failure (HF) in recent years, driven by significant strides in guideline-directed medical therapy (GDMT). Despite this, HF is still associated with high levels of morbidity and mortality, and most patients do not receive optimal medical therapy. In conjunction with the improvement of GDMT, novel device therapies have been developed to better treat HF. These devices include technology capable of remotely monitoring HF physiology, devices that modulate the autonomic nervous system, and those that structurally change the heart with the ultimate aim of addressing the root causes of HF physiology As these device therapies gradually integrate into the fabric of HF patient care, it becomes increasingly important for modern cardiologists to become familiar with them. Hence, the objective of this review is to shed light on currently emerging devices for the treatment of HF.

Preload Reduction Therapies in Heart Failure

Preload reserve represents an important concept in the normal physiologic responses of the body to meet the changing metabolic demands. The recruitment of preload in healthy patients leads to an increase in effective circulating blood volume with a concomitant increase in cardiac output. However, in the setting of heart failure (HF), preload augmentation may precipitate HF decompensation. In this review, we focus on the role of splanchnic nerve modulation and pharmacological therapeutic interventions to prevent HF decompensation through preload reduction. Furthermore, we explore the emerging device-based approaches for cardiac preload reduction while reviewing the ongoing clinical trials.

Neuromodulation Therapies in Heart Failure: A State-of-the-Art Review

Heart failure (HF) continues to impact the population globally with increasing prevalence. While the pathophysiology of HF is quite complex, the dysregulation of the autonomic nervous system, as evident in heightened sympathetic activity, serves as an attractive pathophysiological target for newer therapies and HF. The degree of neurohormonal activation has been found to correlate to the severity of symptoms, decline in functional capacity, and mortality. Neuromodulation of the autonomic nervous system aims to restore the balance between sympathetic nervous system and the parasympathetic nervous system. Given that autonomic dysregulation plays a major role in the development and progression of HF, restoring this balance may potentially have an impact on the core pathophysiological mechanisms and various HF syndromes. Autonomic modulation has been proposed as a potential therapeutic strategy aimed at reduction of systemic inflammation. Such therapies, complementary to drug and device-based therapies may lead to improved patient outcomes and reduce disease burden. Most professional societies currently do not provide a clear recommendation on the use of neuromodulation techniques in HF. These include direct and indirect vagal nerve stimulation, spinal cord stimulation, baroreflex activation therapy, carotid sinus stimulation, aortic arch stimulation, splanchnic nerve modulation, cardiopulmonary nerve stimulation, and renal sympathetic nerve denervation. In this review, we provide a comprehensive overview of neuromodulation in HF.

The Sympathetic Nervous System in Hypertensive Heart Failure with Preserved LVEF

The neurohormonal model of heart failure (HF) pathogenesis states that a reduction in cardiac output caused by cardiac injury results in sympathetic nervous system (SNS) activation, that is adaptive in the short-term and maladaptive in the long-term. This model has proved extremely valid and has been applied in HF with a reduced left ventricular (LV) ejection fraction (LVEF). In contrast, it has been undermined in HF with preserved LVEF (HFpEF), which is due to hypertension (HTN) in the vast majority of the cases. Erroneously, HTN, which is the leading cause of cardiovascular disease and premature death worldwide and is present in more than 90% of HF patients, is tightly linked with SNS overactivity. In this paper we provide a contemporary overview of the contribution of SNS overactivity to the development and progression of hypertensive HF (HHF) as well as the clinical implications resulting from therapeutic interventions modifying SNS activity. Throughout the manuscript the terms HHF with preserved LVEF and HfpEF will be used interchangeably, considering that the findings in most HFpEF studies are driven by HTN.

Device Interventions for Heart Failure

Despite remarkable advances in drug therapy for heart failure (HF), the residual HF-related morbidity, mortality, and hospitalizations remain substantial across all HF phenotypes, and significant proportions of patients with HF remain symptomatic despite optimal drug therapy. Driven by these unmet clinical needs, the exponential growth of transcatheter interventions, and a recent shift in the regulatory landscape of device-based therapies, novel device-based interventions have emerged as a potential therapy for various phenotypes of HF. Device-based interventions can overcome some of the limitations of drug therapy (eg, intolerance, nonadherence, inconsistent delivery, and recurrent and long-term cost) and can target some HF-related pathophysiologic pathways more effectively than drug therapy. This paper reviews the current evolving landscape of device-based interventions in HF and highlights critical points related to implementation of these therapies in the current workflow of HF management.

Pathophysiological Rationale and Clinical Evidence for Neurohormonal Modulation in Heart Failure with Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) is a heterogeneous syndrome resulting from the interaction between cardiac diseases, comorbidities and ageing. HFpEF is characterised by the activation of neurohormonal axes, namely of the renin-angiotensin-aldosterone system and the sympathetic nervous system, although to a lesser extent compared with heart failure with reduced ejection fraction. This provides a rationale for neurohormonal modulation as a therapeutic approach for HFpEF. Nonetheless, randomised clinical trials have failed to demonstrate a prognostic benefit from neurohormonal modulation therapies in HFpEF, with the sole exception of patients with left ventricular ejection fraction in the lower range of normality, for whom the American guidelines suggest that such therapies may be considered. In this review, the pathophysiological rationale for neurohormonal modulation in HFpEF is summarised and the clinical evidence on pharmacological and nonpharmacological approaches backing current recommendations discussed.

Renal Denervation Helps Preserve the Ejection Fraction by Preserving Endocardial-Endothelial Function during Heart Failure

Renal denervation (RDN) protects against hypertension, hypertrophy, and heart failure (HF); however, it is not clear whether RDN preserves ejection fraction (EF) during heart failure (HFpEF). To test this hypothesis, we simulated a chronic congestive cardiopulmonary heart failure (CHF) phenotype by creating an aorta-vena cava fistula (AVF) in the C57BL/6J wild type (WT) mice. Briefly, there are four ways to create an experimental CHF: (1) myocardial infarction (MI), which is basically ligating the coronary artery by instrumenting and injuring the heart; (2) trans-aortic constriction (TAC) method, which mimics the systematic hypertension, but again constricts the aorta on top of the heart and, in fact, exposes the heart; (3) acquired CHF condition, promoted by dietary factors, diabetes, salt, diet, etc., but is multifactorial in nature; and finally, (4) the AVF, which remains the only one wherein AVF is created ~1 cm below the kidneys in which the aorta and vena cava share the common middle-wall. By creating the AVF fistula, the red blood contents enter the vena cava without an injury to the cardiac tissue. This model mimics or simulates the CHF phenotype, for example, during aging wherein with advancing age, the preload volume keeps increasing beyond the level that the aging heart can pump out due to the weakened cardiac myocytes. Furthermore, this procedure also involves the right ventricle to lung to left ventricle flow, thus creating an ideal condition for congestion. The heart in AVF transitions from preserved to reduced EF (i.e., HFpEF to HFrEF). In fact, there are more models of volume overload, such as the pacing-induced and mitral valve regurgitation, but these are also injurious models in nature. Our laboratory is one of the first laboratories to create and study the AVF phenotype in the animals. The RDN was created by treating the cleaned bilateral renal artery. After 6 weeks, blood, heart, and renal samples were analyzed for exosome, cardiac regeneration markers, and the renal cortex proteinases. Cardiac function was analyzed by echocardiogram (ECHO) procedure. The fibrosis was analyzed with a trichrome staining method. The results suggested that there was a robust increase in the exosomes' level in AVF blood, suggesting a compensatory systemic response during AVF-CHF. During AVF, there was no change in the cardiac eNOS, Wnt1, or β-catenin; however, during RDN, there were robust increases in the levels of eNOS, Wnt1, and β-catenin compared to the sham group. As expected in HFpEF, there was perivascular fibrosis, hypertrophy, and pEF. Interestingly, increased levels of eNOS suggested that despite fibrosis, the NO generation was higher and that it most likely contributed to pEF during HF. The RDN intervention revealed an increase in renal cortical caspase 8 and a decrease in caspase 9. Since caspase 8 is protective and caspase 9 is apoptotic, we suggest that RDN protects against the renal stress and apoptosis. It should be noted that others have demonstrated a role of vascular endothelium in preserving the ejection by cell therapy intervention. In the light of foregoing evidence, our findings also suggest that RDN is cardioprotective during HFpEF via preservation of the eNOS and accompanied endocardial-endothelial function.

Safety, Feasibility of Controllable Decrease of Vena Cava Pressure by Doraya Catheter in Heart Failure

Lowering elevated central venous pressure may reduce renal dysfunction in acute heart failure (AHF) patients. The Doraya catheter lowers renal venous pressure by creating a gradient in the inferior vena cava below the renal veins. Here, we present a first-in-human feasibility study of the Doraya catheter performed on 9 AHF patients. We assessed the safety, feasibility, and acute clinical (hemodynamic and renal) effects of transient Doraya catheter deployment when added to the standard diuretic-based regimen in AHF patients with a poor diuretic response. The procedures decreased central venous pressure from 18.4 ± 3.8 mm Hg to 12.4 ± 4.7 mm Hg (P < 0.001) and improved mean diuresis and clinical signs of congestion. No device-related serious adverse events were observed. Thus, Doraya catheter deployment was safe and feasible in AHF patients. (First In Human Study of the Doraya Catheter for the Treatment of AHF Patients; NCT03234647).

Advances in novel devices for the treatment of heart failure

Heart failure (HF) is one of the leading causes of global health impairment. Current drugs are still limited in their effectiveness in the treatment and reversal of HF: for example, drugs for acute HF (AHF) help to reduce congestion and relieve symptoms, but they do little to improve survival; most conventional drugs for HF with preserved ejection fraction (HFpEF) do not improve the prognosis; and drugs have extremely limited effects on advanced HF. In recent years, progress in device therapies has bridged this gap to a certain extent. For example, the availability of the left ventricular assist device has brought new options to numerous advanced HF patients. In addition to this recognizable device, a range of promising novel devices with preclinical or clinical trial results are emerging that seek to treat or reverse HF by providing circulatory support, repairing structural abnormalities in the heart, or providing electrical stimulation. These devices may be useful for the treatment of HF. In this review, we summarized recent advances in novel devices for AHF, HFpEF, and HF with reduced ejection fraction (HFrEF) with the aim of providing a reference for clinical treatment and inspiration for novel device development.

Transcatheter interventions for heart failure

Despite significant advances in the medical management of patients living with heart failure, there continues to be significant morbidity and mortality associated with the condition. There is a growing need for research and development of additional modalities to fill the management and treatment gaps, reduce hospitalisations and improve the quality of life for patients living with heart failure. In the last decade, there has been a rapid rise in the use of non-valvular catheter-based therapies for the management of chronic heart failure to complement existing guideline-directed management. They target well-defined mechanistic and pathophysiological processes critical to the progression of heart failure including left ventricular remodelling, neurohumoral activation, and congestion. In this review, we will explore the physiology, rationale, and current stages of the clinical development of the existing procedures.

Heart failure: an update from the last years and a look at the near future

In the last years, major progress occurred in heart failure (HF) management. Quadruple therapy is now mandatory for all the patients with HF with reduced ejection fraction. Whilst verciguat is becoming available across several countries, omecamtiv mecarbil is waiting to be released for clinical use. Concurrent use of potassium-lowering agents may counteract hyperkalaemia and facilitate renin-angiotensin-aldosterone system inhibitor implementations. The results of the EMPagliflozin outcomE tRial in Patients With chrOnic heaRt Failure With Preserved Ejection Fraction (EMPEROR-Preserved) trial were confirmed by the Dapagliflozin in Heart Failure with Mildly Reduced or Preserved Ejection Fraction (DELIVER) trial, and we now have, for the first time, evidence for treatment of also patients with HF with preserved ejection fraction. In a pre-specified meta-analysis of major randomized controlled trials, sodium-glucose co-transporter-2 inhibitors reduced all-cause mortality, cardiovascular (CV) mortality, and HF hospitalization in the patients with HF regardless of left ventricular ejection fraction. Other steps forward have occurred in the treatment of decompensated HF. Acetazolamide in Acute Decompensated Heart Failure with Volume Overload (ADVOR) trial showed that the addition of intravenous acetazolamide to loop diuretics leads to greater decongestion vs. placebo. The addition of hydrochlorothiazide to loop diuretics was evaluated in the CLOROTIC trial. Torasemide did not change outcomes, compared with furosemide, in TRANSFORM-HF. Ferric derisomaltose had an effect on the primary outcome of CV mortality or HF rehospitalizations in IRONMAN (rate ratio 0.82; 95% confidence interval 0.66-1.02; P = 0.070). Further options for the treatment of HF, including device therapies, cardiac contractility modulation, and percutaneous treatment of valvulopathies, are summarized in this article.

Transvenous Right Greater Splanchnic Nerve Ablation in Heart Failure and Preserved Ejection Fraction: First-in-Human Study

BACKGROUND

Ablation of the right-sided greater splanchnic nerve (GSN) can reduce excessive splanchnic vasoconstriction, potentially improving the handling of volume shifts in patients with heart failure with preserved ejection fraction (HFpEF).

OBJECTIVES

The purpose of this study was to assess a novel catheter procedure of right-sided GSN ablation to treat HFpEF: splanchnic ablation for volume management.

METHODS

This trial included 11 HFpEF patients (8 women, age 70 ± 8 years) with New York Heart Association functional class II or III symptoms, ejection fraction ≥50%, and elevated pulmonary capillary wedge pressure at rest or with exercise. After splanchnic ablation for volume management, follow-up at 1, 3, 6, and 12 months included 6-minute walk test, Kansas City Cardiomyopathy Questionnaire (KCCQ), and echocardiography.

RESULTS

There were no device-related adverse cardiac events or clinical sequelae following right GSN ablation through 12 months. Patients experienced clinical improvements by 1 month that were sustained through 12 months. KCCQ score improved from baseline median 48 (IQR: 35-52) to 65 (IQR: 58-77) at 1 month and 80 (IQR: 77-88) at 12 months (P &lt; 0.05). The 6-minute walk test distance increased from baseline 292 ± 82 m to 341 ± 88 m at 1 month and 359 ± 75 m at 12 months (P &lt; 0.05). The NT-proBNP decreased from a baseline mean of 1,292 ± 1,186 pg/mL to 1,202 ± 797 pg/mL (P = 0.585) at 1 month, to 472 ± 226 pg/mL (P = 0.028) at 6 months, and to 379 ± 165 pg/mL (P = 0.039) at 12 months.

CONCLUSIONS

In this open-label, single-arm feasibility study, right-sided GSN ablation was safe and improved mostly subjective clinical metrics in patients with HFpEF over 12 months. (Endovascular GSN Ablation in Subjects With HFpEF; NCT04287946).

Right and left ventricular structures and functions in acute HFpEF: comparing the hypertensive pulmonary edema and worsening heart failure phenotypes

BACKGROUND

Limited data are available on right (RV) and left (LV) ventricular structures and functions in acute heart failure with preserved ejection fraction (AHF-pEF) presenting with hypertensive pulmonary edema (APE) versus predominant peripheral edema (peHF).

METHODS AND RESULTS

In a prospective study of consecutive patients with AHF-pEF, 80 patients met inclusion and not exclusion criteria, and underwent echocardiographic and laboratory examination in the emergency ward. The survived (94%) were re-evaluated at the discharge. At admission, systolic, diastolic, pulse blood pressure (BP), and high sensitivity troponin I were higher (all P < 0.05) with APE than with peHF while brain-type natriuretic peptide (BNP), hemoglobin and estimated glomerular filtration rate (eGFR) did not differ between the two phenotypes. LV volumes and EF were comparable between APE and peHF, but APE showed lower relative wall thickness (RWT), smaller left atrial (LA) volume, higher pulse pressure/stroke volume (PP/SV), and higher ratio between the peak velocities of the early diastolic waves sampled by traditional and tissue Doppler modality (mitral E/e', all P < 0.05). Right ventricular and atrial (RA) areas were smaller, tricuspid anular plane systolic excursion (TAPSE) and estimated pulmonary artery peak systolic pressure (sPAP) were higher with APE than with peHF (all P < 0.05) while averaged degree of severity of tricuspid insufficiency was greater with peHF than with APE. At discharge, PP/SV, mitral E/e', sPAP, RV sizes were reduced from admission in both phenotypes (all P < 0.05) and did not differ anymore between phenotypes, whereas LV EF and TAPSE did not show significant changes over time and treatments.

CONCLUSION

In AHF-pEF, at comparable BNP and LV EF, hypertensive APE showed eccentric LV geometry but smaller RV and RA sizes, and higher RV systolic function, increased LV ventricular filling and systemic arterial loads. AHF resolution abolished the differences in PP/SV and LV diastolic load between APE and peHF whereas APE remained associated with more eccentric RV and higher TAPSE.

Endovascular Ablation of the Right Greater Splanchnic Nerve in Heart Failure with Preserved Ejection Fraction: Early Results of the REBALANCE-HF Trial Roll-in Cohort

Aims

In heart failure (HF) with preserved ejection fraction (HFpEF), excessive redistribution of blood volume into the central circulation leads to elevations of intracardiac pressures with exercise limitations. Splanchnic ablation for volume management (SAVM) has been proposed as a therapeutic intervention. Here we present preliminary safety and efficacy data from the initial roll‐in cohort of the REBALANCE‐HF trial.

Methods and results

The open‐label (roll‐in) arm of REBALANCE‐HF will enrol up to 30 patients, followed by the randomized, sham‐controlled portion of the trial (up to 80 additional patients). Patients with HF, left ventricular ejection fraction (LVEF) ≥50%, and invasive peak exercise pulmonary capillary wedge pressure (PCWP) ≥25 mmHg underwent SAVM. Baseline and follow‐up assessments included resting and exercise PCWP, New York Heart Association (NYHA) class, Kansas City Cardiomyopathy Questionnaire (KCCQ), 6‐min walk test, and N‐terminal pro‐B‐type natriuretic peptide (NT‐proBNP). Efficacy and safety were assessed at 1 and 3 months. Here we report on the first 18 patients with HFpEF that have been enrolled into the roll‐in, open‐label arm of the study across nine centres; 14 (78%) female; 16 (89%) in NYHA class III; and median (interquartile range) age 75.2 (68.4–81) years, LVEF 61.0 (56.0–63.2)%, and average (standard deviation) 20 W exercise PCWP 36.4 (±8.6) mmHg. All 18 patients were successfully treated. Three non‐serious moderate device/procedure‐related adverse events were reported. At 1‐month, the mean PCWP at 20 W exercise decreased from 36.4 (±8.6) to 28.9 (±7.8) mmHg (p < 0.01), NYHA class improved by at least one class in 33% of patients (p = 0.02) and KCCQ score improved by 22.1 points (95% confidence interval 9.4–34.2) (p < 0.01).

Conclusion

The preliminary open‐label results from the multicentre REBALANCE‐HF roll‐in cohort support the safety and efficacy of SAVM in HFpEF. The findings require confirmation in the ongoing randomized, sham‐controlled portion of the trial.

Venous Tone and Stressed Blood Volume in Heart Failure: JACC Review Topic of the Week

A number of pathologic processes contribute to the elevation in cardiac filling pressures in heart failure (HF), including myocardial dysfunction and primary volume overload. In this review, we discuss the important role of the venous system and the concepts of stressed blood volume and unstressed blood volume. We review how regulation of venous tone modifies the distribution of blood between these 2 functional compartments, the physical distribution of blood between the pulmonary and systemic circulations, and how these relate to the hemodynamic abnormalities observed in HF. Finally, we review recently applied methods for estimating stressed blood volume and how they are being applied to the results of clinical studies to provide new insights into resting and exercise hemodynamics and therapeutics for HF.

Targeting Preload in Heart Failure: Splanchnic Nerve Blockade and Beyond

Preload augmentation represents a critical mechanism for the cardiovascular system to increase effective circulating blood volume to increase cardiac filling pressures and, subsequently, for the heart to increase cardiac output. The splanchnic vascular compartment is the primary source of vascular capacity and thus the primary target for preload recruitment in humans. Under normal conditions, sympathetic stimulation of these primary venous vessels promotes the shift of blood from the splanchnic to the thoracic compartment and elevates preload and cardiac output. However, in heart failure, since filling pressures may be elevated at rest due to decreased venous capacitance, incremental recruitment of preload to enhance cardiac output may exacerbate congestion and limit exercise capacity. Accordingly, recent attention has focused on therapies designed to regulate splanchnic vascular redistribution to improve cardiac filling pressures and patient-centered outcomes such as quality of life and exercise capacity in patients with heart failure. In this review, we discuss the relevance of splanchnic circulation as a venous reservoir, the contribution of stressed blood volume to heart failure pathogenesis, and the implications for pharmacological therapeutic interventions to prevent heart failure decompensation. Further, we review emerging device-based approaches for cardiac preload reduction such as partial/complete occlusion of the superior vena cava or the inferior vena cava.

Peripheral Venous Pressure-Assisted Exercise Stress Echocardiography in the Evaluation of Pulmonary Hypertension During Exercise in Patients With Suspected Heart Failure With Preserved Ejection Fraction

BACKGROUND

Identification of elevated pulmonary artery (PA) pressures during exercise may provide diagnostic, prognostic, and therapeutic implications in heart failure with preserved ejection fraction. Although widely performed, exercise stress echocardiography may underestimate true PA pressures due to the difficulty in estimating right atrial pressure (RAP) during exercise. We hypothesized that peripheral venous pressure (PVP) could allow for reliable estimation of RAP, and thus PA pressures during exercise stress echocardiography.

METHODS

In protocol 1, we investigated the accuracy of PVP compared with simultaneously measured RAP at rest and during exercise right heart catheterization in 19 subjects. In protocol 2, we examined whether the addition of PVP to Doppler exercise echocardiography (tricuspid regurgitant velocity) would increase the ability to identify exercise-induced pulmonary hypertension compared with inferior vena cava-based RAP estimation in 60 patients with dyspnea.

RESULTS

In protocol 1, PVP was strongly correlated with simultaneously measured RAP at rest and during exercise (r=0.77 and 0.90), with little overestimation of invasively measured RAP (bias 3.4 mm Hg at rest and 1.7 mm Hg during exercise). In protocol 2, PVP increased dramatically during exercise echocardiography (14±5 mm Hg) while an increase in inferior vena cava-based RAP was modest (6±4 mm Hg). Exercise PA pressures calculated from PVP and tricuspid regurgitant velocity were significantly higher than those estimated from inferior vena cava and the use of PVP increased the proportion of patients with exercise-induced pulmonary hypertension from 40% to 68%.

CONCLUSIONS

PVP may prevent underestimation of PA pressures during exercise echocardiography and could be a preferred approach to identify exercise-induced pulmonary hypertension in patients with suspected heart failure with preserved ejection fraction.

Early Hemodynamic Changes following Surgical Ablation of the Right Greater Splanchnic Nerve for the Treatment of Heart Failure with Preserved Ejection Fraction

Background: Permanent ablation of the right greater splanchnic nerve (GSN) has previously been demonstrated to improve quality of life and functional outcomes, as well as reduce abnormally high intracardiac filling pressures, in patients with heart failure with preserved ejection fraction (HFpEF) at 1, 3 and 12 months following the procedure. We hypothesize that hemodynamic changes that ensue from surgical right GSN ablation would be apparent as early as 24 h after the medical intervention. Methods and Results: This is a prespecified analysis of a single-arm, two-center, open-label study evaluating the effects of right GSN ablation via thoracoscopic surgery in HFpEF patients with pulmonary capillary wedge pressure (PCWP) ≥15 mmHg at rest or ≥25 mmHg with supine cycle ergometry. A total of seven patients (median age 67 years, 29% female) underwent GSN removal followed by invasive right heart catheterization within 24 h. GSN ablation resulted in a significant reduction in PCWP 24 h after the procedure compared to baseline for both 20 W exercise (baseline (28.0 ± 4.3 mmHg) to 24 h (19.6 ± 6.9 mmHg); p = 0.0124) and peak exercise (baseline (25.6 ± 2.4 mmHg) to 24 h (17.4 ± 5.9 mmHg); p = 0.0025). There were no significant changes in resting or leg-up hemodynamics. Conclusions: Permanent right GSN ablation leads to a reduction in intracardiac filling pressures during exercise, apparent as early as 24 h following the procedure.

Remote Hind-Limb Ischemia Mechanism of Preserved Ejection Fraction During Heart Failure

During acute heart failure (HF), remote ischemic conditioning (RIC) has proven to be beneficial; however, it is currently unclear whether it also extends benefits from chronic congestive, cardiopulmonary heart failure (CHF). Previous studies from our laboratory have shown three phases describing CHF viz. (1) HF with preserved ejection fraction (HFpEF), (2) HF with reduced EF (HFrEF), and (3) HF with reversed EF. Although reciprocal organ interaction, ablation of sympathetic, and calcium signaling genes are associated with HFpEF to HFrEF, the mechanism is unclear. The HFrEF ensues, in part, due to reduced angiogenesis, coronary reserve, and leakage of endocardial endothelial (EE) and finally breakdown of the blood-heart barrier (BHB) integrity. In fact, our hypothesis states that a change in phenotype from compensatory HFpEF to decompensatory HFrEF is determined by a potential decrease in regenerative, proangiogenic factors along with a concomitant increase in epigenetic memory, inflammation that combinedly causes oxidative, and proteolytic stress response. To test this hypothesis, we created CHF by aorta-vena-cava (AV) fistula in a group of mice that were subsequently treated with that of hind-limb RIC. HFpEF vs. HFrEF transition was determined by serial/longitudinal echo measurements. Results revealed an increase in skeletal muscle musclin contents, bone-marrow (CD71), and sympathetic activation (β2-AR) by RIC. We also observed a decrease in vascular density and attenuation of EE-BHB function due to a corresponding increase in the activity of MMP-2, vascular endothelial growth factor (VEGF), caspase, and calpain. This decrease was successfully mitigated by RIC-released skeletal muscle exosomes that contain musclin, the myokine along with bone marrow, and sympathetic activation. In short, based on proteome (omics) analysis, ∼20 proteins that appear to be involved in signaling pathways responsible for the synthesis, contraction, and relaxation of cardiac muscle were found to be the dominant features. Thus, our results support that the CHF phenotype causes dysfunction of cardiac metabolism, its contraction, and relaxation. Interestingly, RIC was able to mitigate many of the deleterious changes, as revealed by our multi-omics findings.

Device Therapy in Chronic Heart Failure: JACC State-of-the-Art Review

The regulatory landscape for device-based heart failure (HF) therapies has seen a major shift in the last 7 years. In 2013, the U.S. Food and Drug Administration released guidance for early feasibility and first-in-human studies, thereby encouraging device innovation, and in 2016 the U.S. Congress authorized the Breakthrough Devices Program to expedite access for Americans to innovative devices indicated for diagnosis and treatment of serious illnesses, such as HF. Since December 2016, there has been an increase in the number of HF devices for which manufacturers are seeking approval through the breakthrough designation pathway. This has led to a rapid uptake in the development and evaluation of device-based HF therapies. This article reviews the current and future landscape of device therapies for chronic HF and associated comorbidities and the regulatory environment that is driving current and future innovation.

CENTRAL AND PERIPHERAL SYMPATHETIC ACTIVATION IN HEART FAILURE

The sympathetic nervous system overdrive occurring in heart failure has been reported since more than half a century. Refinements in the methodological approaches to assess human sympathetic neural function have allowed during recent years to better define various aspects related to the neuroadrenergic alteration. These include 1) the different participation of the individual regional sympathetic cardiovascular districts at the process, 2) the role of the central nervous system in determining the neuroadrenergic overdrive, 3) the involvement of baroreflex, cardiopulmonary reflex and chemoreflex mechanisms in the phoenomenon, which is also closely linked to inflammation and the immune reaction, 4) the relationships with the severity of the disease, its ischaemic or idiopathic nature and the preserved or reduced left ventricular ejection fraction and 5) the adverse functional and structural impact of the sympathetic activation on cardiovascular organs, such as the brain, the heart and the kidneys. Information have been also gained on the active role exerted by the sympathetic activation on the disease outcome and its potential relevance as target of the therapeutic interventions based on non-pharmacological, pharmacological and invasive approaches, including the renal denervation, the splanchnic sympathetic nerve ablation and the carotid baroreflex stimulation. The still undefined aspects of the neurogenic alterations and the unmet goals of the therapeutic approach having the sympathetic activation as a target of the intervention will be finally mentioned.