Developing Novel RF Ablation Systems: Challenges and Opportunities in a Mature Market

Atrial fibrillation, chronic pain, tumorous growths, venous insufficiency, and a host of other ailments are now being treated with the use of Radiofrequency Ablation (RFA) as a first-line treatment capable of disabling errantly firing nerves, redirecting blood flow, or destroying malignant tissue without the need for more invasive or chronic therapies. The ability of RFA to access and treat such a breadth of ailments has led to these systems becoming ubiquitous in nearly every clinical specialty. From the perspective of the medical device development community, widespread adoption of RFA has led to a maturing of the market and created challenges for new entrants or to incumbent firms wishing to improve on their existing designs.

Looking deeper at the current state of the art, though, there are numerous opportunities for clever developers to capitalize on, to advance the field, and to improve patient care. These opportunities include improved in silico modeling, minimally invasive and targeted therapies, and more accessible systems.

Improved RF Ablation Modeling

Developing a novel RFA system will require the development team to make early decisions that ripple through the program. For instance, while an instrument’s end effector design may be thought of as a primarily mechanical consideration, it has significant impacts on both clinical tissue effects and RF generator output requirements. The number of design permutations is large, and no optimal closed-form solution exists, often leading to sub-optimal results or the dreaded “never-ending loop” of development.

A solution that bridges these challenges is the development of Improved Theoretical Models for RF Ablation. As Beranjo writes: Improved Models “...provide vital information on the electrical and thermal behavior of ablation rapidly and at low cost, quantifying the effect of various extrinsic and intrinsic factors on the electrical current and temperature distribution. Consequently, they facilitate the assessment of the feasibility of new electrode geometries, and new protocols for delivering electrical power.”

Development of systems that advance the state of the art in these factors require multiple iterative development loops to ensure safety and efficacy of the developers’ assumptions, which drives cost of development up and limits the ability to innovate in this space. The development and validation of better in silico models can significantly reduce that cost by aiding in understanding current density and electrode heating, and ablation radius and neighboring tissue effects, and improve opportunities for specific tissue interventions. Better models can reduce the number of iterative cycles of development before pre-clinical work and can accelerate overall development time and bring more novel solutions to the approval phase faster. Far from being an academic curiosity, in silico modeling is now regularly being seen as a component in FDA submissions².

Minimally Invasive, Minimally Destructive Procedures

Less invasive procedures are preferable to the patient, to the clinician, to payers, and to firms looking to service all three of these stakeholder communities. They reduce clinic time and recovery time, and are often more cost-effective. However, the ability to affect a minimally invasive treatment can be limited by a lack of meaningful feedback on the progression and efficacy of the therapy.

RFA developers have an opportunity here that is two-fold. First, to improve RFA systems such that they are compatible with better, more accurate perioperative imaging tools. While some tools already exist for visualizing ablation outcomes (such as ultrasound, where microbubbles created from vaporization of ablated tissue appear as hyperechogenic regions), the specificity and accuracy of these imaging modalities is low. MRI-guided ablation has the potential for better specificity, but system-level complications related to delivering RFA within an MRI machine presently limit its adoption. A novel RFA system that offers a true improvement would be one in which the ablation zone can be better visualized in real-time such that intraoperative confirmation is assured.

Second, there is an opportunity to improve instrument design and therapy delivery to allow more tissue specificity and therapeutic accuracy. Complications related to RFA are minimal but, due to the radius of ablation, healthy tissue is often removed to ensure a complete lesion. In pharmacologic therapies, dosages are specified with high precision and high accuracy, tailored to individual patients, and titrated to specific targets; in RFA (as it exists, today), why do we commonly accept a thermal dosage that is not similarly prescriptive? A novel RFA system would be one in which energy delivery is accurately monitored and able to achieve a specific therapeutic outcome, with minimal collateral damage, and a high level of assurance of success.

More Accessible Systems

RFA is a well-developed procedure, with decades of clinical literature supporting its use in a host of applications. Despite that, systems on the market remain costly, challenging to use, and require a significant investment in expense and training on behalf of clinics and healthcare systems. An opportunity exists to expand access to this technology, using scalable, modular systems that could allow for the development of simple systems for targeted approaches. Improvements in enabling technologies and subsystems have created an opportunity for the development of specific RFA systems that could open these treatments up to more clinicians to provide better care for patients. Clinicians in geographic locations where access to medicine and training in new systems is scarce, would benefit from simpler, more cost-effective RFA systems to improve the care that their patients receive. Improved usability (whether in the form of traditional usability improvements or by means of “smart” systems that minimize the need for extensive clinical judgement in their use) also lead to improved outcomes.

Conclusions

The use of RFA to treat some of the most complex and difficult diseases has led to dramatic reductions in mortality, driven down the complications from more invasive surgical procedures, and created advancements that were unpredictable 30 years ago. Despite the reach and size of this marketplace, there are still many frontiers to expand and opportunities to explore. A mature market is simply one that is ready for disruption, and it is incumbent upon us to seek opportunities to do just that — for the benefit of the patients that rely on us.

References

1. Berjano, E.J. Theoretical modeling for radiofrequency ablation: state-of-the-art and challenges for the future. BioMed Eng OnLine 5, 24 (2006).
2. Accessing the Credibility of Computational Modeling and Simulation in Medical Device Submissions, Draft Guidance for Industry and Food and Drug Administration Staff, Dec 23, 2021.

About The Author:

Dr. Daniel Friedrichs leads development engineering efforts at Minnetronix Medical for commercialization of surgical energy devices including in vivo electroporation systems, RF ablation systems, ultrasound and plasma delivery devices, and other energy-based medical, surgical, and drug-delivery therapies. Dr. Friedrichs is named on more than 35 patents and has worked with an extensive network of clients seeking to commercialize a wide array of technologies. New product development, unmet needs identification, technology development and ideation, and user-centered design are some of his specialties. Prior to joining Minnetronix, Dr. Friedrichs was with the University of Colorado Boulder and Covidien. He holds BS and PhD degrees in electrical engineering and is a licensed professional engineer.