Axon Therapies: Revolutionizing Heart Failure Treatment Through Splanchnic Ablation

For years, patients living with heart failure with preserved ejection fraction (HFpEF) have faced a painful paradox. They have a form of heart failure every bit as serious as reduced ejection fraction, yet their treatment options remain strikingly limited.

Axon Therapies, a privately held medical device company, is trying to change that. Based in Northern California, the company has developed a novel procedure called Splanchnic Ablation for Volume Management (SAVM)—a targeted therapy designed to address the root physiology behind HFpEF rather than just managing symptoms.

Backed by a growing body of clinical data and strong investor confidence, Axon is aiming to reshape how clinicians think about heart failure treatment.

Why Heart Failure with Preserved Ejection Fraction Needs New Approaches

Heart failure with preserved ejection fraction accounts for roughly half of all heart failure cases worldwide, and it carries a grim statistic: only half of those diagnosed survive beyond five years. While SGLT2 inhibitors have recently provided modest benefits for some patients, most still lack effective, durable therapies.

HFpEF patients experience elevated left-sided filling pressures—a condition that makes even small amounts of exertion exhausting. The disease is driven in part by an overactive sympathetic nervous system (SNS) that constricts blood vessels and increases cardiac pressure.

Axon’s scientists studied how this overactivation affects the splanchnic circulation—the vast network of blood vessels feeding the abdominal organs. Using hemodynamic monitoring systems, catheter-based pressure sensors, and cardiac imaging, the team confirmed that persistent splanchnic constriction traps blood centrally, straining the heart over time.

In developing its SAVM procedure, Axon is tackling this problem directly by disrupting the nerve signals that cause that constriction, restoring balance to the body’s volume distribution system.

Targeting the Splanchnic Nervous System

At the core of Axon Therapies’ approach is a focus on the greater splanchnic nerve (GSN)—a neural pathway that controls how blood volume is distributed between the abdominal organs and the central circulation.

The splanchnic bed, which includes the liver, spleen, stomach, and intestines, holds as much as half of the body’s total blood volume. Under normal conditions, this region acts as a dynamic reservoir, expanding and contracting in response to the body’s needs. But in patients with heart failure, the sympathetic nervous system becomes chronically overactive, constricting these vessels and forcing excess blood toward the heart. The result is elevated pressure, congestion, and worsening symptoms.

Axon’s Splanchnic Ablation for Volume Management (SAVM) procedure aims to interrupt this cycle. By selectively disrupting the nerve signals that drive that constriction, the therapy helps restore the body’s ability to balance blood volume naturally.

The concept emerged from years of research using hemodynamic mapping, pressure-volume loop analyses, and catheter-based vascular measurements—techniques that quantify how blood moves through the circulatory system in real time. These tools allowed Axon’s engineers and clinicians to trace the exact physiological mechanism they now target.

The Satera System: A Minimally Invasive Solution

To deliver this therapy, Axon developed the Satera System, a catheter-based platform designed for precision and safety. The system allows physicians to perform the SAVM procedure using a venous access approach rather than open surgery.

During treatment, the Axon Ablation Catheter is inserted through the femoral vein and guided—using fluoroscopic imaging and intravascular ultrasound—to a target vessel near the right greater splanchnic nerve. Once in position, the system delivers controlled radiofrequency energy to ablate the nerve, blocking sympathetic signals that drive chronic splanchnic constriction.

Each ablation is carefully monitored through temperature sensors, impedance feedback, and electrophysiological mapping to ensure accuracy and minimize collateral damage. The procedure typically lasts under an hour and can be performed in a cardiac catheterization lab using equipment already familiar to most interventional cardiologists.

It’s an elegant convergence of cardiology, neuromodulation, and interventional device engineering—one that transforms a complex physiological insight into a practical, repeatable therapy.

Clinical Evidence and Results

Early data from Axon Therapies’ feasibility studies suggest that Splanchnic Ablation for Volume Management (SAVM) could meaningfully improve both quality of life and functional capacity for patients with HFpEF.

In a pilot study of eleven patients, the procedure produced sustained benefits over twelve months without any device-related cardiac complications. Key outcomes included:

• Quality of life: Kansas City Cardiomyopathy Questionnaire (KCCQ) scores improved from a median of 48 at baseline to 80 at twelve months.
• Exercise capacity: Six-minute walk test distance increased from an average of 292 to 359 meters.
• Biomarkers: NT-proBNP levels dropped from roughly 1,300 pg/mL to under 400 pg/mL at twelve months, signaling improved cardiac function.

These improvements were confirmed in a roll-in cohort for the REBALANCE-HF feasibility IDE trial, which continues to evaluate safety and durability in approximately 120 patients.

Clinical teams collect data using echocardiography, right heart catheterization, and noninvasive hemodynamic monitoring to measure treatment effects. All procedural data are recorded through digital imaging systems and cloud-based analysis platforms, allowing investigators to compare real-time hemodynamics across sites.

The precision of the device and the rigor of the data collection have made SAVM one of the most closely watched emerging therapies in interventional cardiology.

How the Work Gets Done

Behind every elegant medical device lies an ecosystem of engineering tools, testing equipment, and specialized labs that turn a clinical concept into a working therapy. Axon Therapies is no exception.

The company’s R&D operations blend traditional biomedical engineering with digital precision. Early prototypes of the Satera System are tested using vascular flow simulators, benchtop catheter models, and tissue-mimicking phantoms that replicate the human splanchnic anatomy. These setups allow engineers to refine catheter flexibility, thermal spread, and energy delivery parameters before moving to animal or human studies.

Once a design iteration passes safety benchmarks, it advances through preclinical validation labs equipped with radiofrequency energy generators, electrophysiological monitoring systems, and thermal imaging cameras to verify ablation depth and temperature consistency. Each phase produces detailed datasets analyzed through simulation software and finite element modeling tools that predict how the system will behave in vivo.

For manufacturing and quality control, Axon works with contract development and manufacturing organizations (CDMOs) that specialize in sterile assembly, catheter component fabrication, and electrical system validation. These partnerships give the company access to advanced infrastructure without carrying the heavy capital burden typical of vertically integrated device firms.

It’s a modern model for medical device development—lean, data-rich, and built around rapid iteration. Every test, model, and validation loop moves the Satera System closer to a future where managing heart failure could become faster, safer, and far more humane.

Funding and Development Timeline

Axon Therapies recently raised $32 million in Series A funding, capital that will support its randomized feasibility trials and accelerate pivotal study preparation. The investment reflects increasing confidence in interventional solutions that target autonomic control of cardiovascular function—a space that remains largely untapped.

The funding will allow Axon to complete the REBALANCE-HF trial, expand manufacturing capabilities for the Satera System, and prepare regulatory submissions for IDE and CE Mark approval pathways.

Behind the scenes, development depends on a complex ecosystem of hardware engineering and clinical validation. Axon’s team works with radiofrequency energy generators, bench testing rigs, and vascular flow simulators to refine procedural safety and device reliability. In parallel, preclinical labs and regulatory testing facilities ensure the technology meets performance and biocompatibility standards.

With its strong patent estate and growing clinical data, the company is approaching the inflection point where engineering excellence and clinical evidence begin to merge into a viable therapy.

Competitive Positioning and Market Opportunity

Axon Therapies occupies a rare position in the cardiovascular landscape. While most interventional heart failure devices focus on mechanical or electrical support, Axon is the only company directly targeting splanchnic nerve modulation to control blood volume.

This distinction matters. Competing neuromodulation systems, such as Barostim and Rheos, target baroreceptors to influence systemic blood pressure, not regional volume distribution. Axon’s SAVM therapy, in contrast, seeks to reset the body’s natural volume balance—addressing one of the primary physiological drivers of HFpEF.

The procedure’s design also makes it operationally attractive. It’s minimally invasive, typically completed in under an hour, and can be performed in an outpatient cath lab using standard interventional cardiology equipment. Patients are often discharged the same day. For hospitals, that translates into scalable workflow integration without the cost of a new infrastructure buildout.

With HFpEF affecting tens of millions worldwide, and limited device-based options available, Axon’s technology addresses a market opportunity that is both clinically urgent and commercially open. Early adopters in cardiology see SAVM as a potential bridge between pharmacologic management and mechanical intervention—a new category of therapy entirely.

Looking Ahead

Axon Therapies represents a quiet but important shift in how heart failure is being treated. Rather than adding another layer of medication or device complexity, the company is focusing on physiology—on restoring the body’s own capacity to manage volume effectively.

The upcoming results from the REBALANCE-HF trial will determine whether the early promise of SAVM holds up under larger, controlled conditions. If the data continue to align, the therapy could redefine how clinicians approach fluid management in heart failure, particularly for patients with preserved ejection fraction who have long lacked good options.

Beyond the science, Axon’s work underscores how device innovation now relies on tight integration between clinical feedback, engineering iteration, and data analytics. The company’s use of shared testing facilities, advanced simulation tools, and flexible manufacturing partnerships mirrors how the next generation of medtech firms are being built—fast, precise, and capital efficient.

For patients living with HFpEF, a condition defined by endurance and limitation, a one-hour outpatient procedure that restores balance rather than masking symptoms could feel like the future arriving early.