Clinical Needs Should Drive Innovation

Jennifer N. Avari Silva, MD^{1, 2, 3, 4}

Affiliations: ¹Division of Pediatric Cardiology, Washington University School of Medicine, St. Louis, MO;²Department of Biomedical Engineering, McKelvey School of Engineering, Washington University in St. Louis, St. Louis, MO;³Sentiar, Inc, St. Louis, MO;⁴Excera, Inc, St. Louis, MO

Corresponding Author:

Jennifer N. Avari Silva, MD jennifersilva@wustl.edu

Disclosures: I am the co-founder and co-inventor of Sentiar and Excera, Inc. The technology has been licensed from Washington University to both Sentiar and Excera.

Words:

Conflicts: I have no relevant conflicts of disclosure.

The tried-and-true methodology for designing medical devices starts with product ideation and rapid prototyping. But the most vital step starts prior to product ideation—that is, identifying the unmet clinical need. Starting with clear identification of clinical need may take time to fully elucidate and, importantly, may change over time as clinical practices, medical knowledge, and scientific discoveries change the field. Developing tools to address these unmet needs is the goal for medical device developers. When we start with developing tools that address unmet needs, the tools inherently provide added value. Conversely, tools are often developed to implement new technologies without a clear understanding of the need being addressed. Often, these technologies are in search of a clinically relevant use case—these tools become proverbial hammers in search of nails.

In this study from Kumthekar et al¹ in this month’s JCE, we learn the results of early feasibility testing of PeriScope in an animal (porcine) study. PeriScope is a novel percutaneous access tool for epicardial access developed to aid in the implantation of epicardial cardiac implantable electronic devices (CIEDs) in both pediatric and congenital patients who require systems at a young age. The clinical conundrum is that young patients who need CIEDs will often require lifelong devices, with transvenous systems often being delayed into adolescence (or later) due to small stature, linear growth, and concerns for causing venous stenosis or occlusion^{2, 3}. Additionally, patients with congenital heart disease often have abnormal vasculature and anatomy which may prohibit transvenous CIED systems^{4, 5} This clinical problem has been debated rigorously in the pediatric EP community, with reports of transvenous systems placed in some of our youngest and smallest of patients⁶. This has been a longstanding need in the pediatric and congenital community which members of this investigative team have spent years working towards^7-10.

The authors set out to address this issue by creating a tool to ease epicardial device lead placement, and the first step in this multistep plan is epicardial access. The current data presented by Kumthekar et al¹ demonstrate the use of this tool in an immature porcine model (Yorkshire piglets) to test the implant procedure characteristics and efficiencies. Early results are promising, showing the time from skin nick to sheath access in the pericardium was <10 minutes with a mean total procedure time of 16 minutes. Lead characteristics were acceptable, though not excellent, speaking to the need to develop additional new tools. To address the long-term goal of minimally invasive epicardial device implantation, adjunctive technologies will need to be developed, including leads designed for implantation via a minimally invasive approach and tools to simplify minimally invasive generator implantation. Given the breadth of tools that will be required to meet this need, an academic-industry partnership may emerge as a viable path for co-development.

As with all novel tools and procedures, there is a learning curve and PeriScope is no different. Even within this small study with 6 piglets, there was a learning curve for the operator with piglet #1 having a longer procedure time than the rest of the cohort. Understanding learning curves, or assessments of performance over experience, for new technologies/tools and procedures is itself an entire field of study¹¹ which over time has created standard learning curve models for guidance with certain types of procedures, including laparoscopic surgical procedures. With PeriScope, there appeared to be a steep learning curve with increased competency after a short experience (n=1). More experience with a varied user group will be invaluable to determining the true learning curve for the device.

Finally, like many innovations developed to a specific clinical need, creative physicians will find novel, often off-label, use cases for technologies that address their own clinical needs. With the growing performance of epicardial ablation, accessing the epicardial space is no longer a need relegated to pediatric and congenital device implants, but is now an emerging need in adult, pediatric and congenital ablation. These changing needs over time are to be expected and reflect advances in medical knowledge and scientific discovery.

By nature, cardiac electrophysiologists are innovators. We are fortunate to practice our field at a time when there is an abundance of devices being developed and engineered to address the unmet clinical needs emerging as we learn more about mechanisms of various substrates and develop best practices. Our mission is to ensure that these novel devices are practical, useful and of benefit to us and our patients.

References:

1. Kumthekar RN OJ, Mass P, M JC, Berul CI. Percutaneous Epicardial Pacing in Infants Using Direct VIsualization: A Feasibility Animal Study. Journal of Cardiovascular Electrophysiology . 2023.

2. Berul CI, Triedman JK, Forbess J, Bevilacqua LM, Alexander ME, Dahlby D, Gilkerson JO and Walsh EP. Minimally invasive cardioverter defibrillator implantation for children: an animal model and pediatric case report. Pacing Clin Electrophysiol . 2001;24:1789-94.

3. Kwak JG, Kim SJ, Song JY, Choi EY, Lee SY, Shim WS, Lee CH, Lee C and Park CS. Permanent epicardial pacing in pediatric patients: 12-year experience at a single center. Ann Thorac Surg . 2012;93:634-9.

4. Maginot KR, Mathewson JW, Bichell DP and Perry JC. Applications of pacing strategies in neonates and infants. Prog Pediatr Cardiol . 2000;11:65-75.

5. Rao V, Williams WG, Hamilton RH, Williams MG, Goldman BS and Gow RM. Trends in pediatric cardiac pacing. Can J Cardiol . 1995;11:993-9.

6. Konta L, Chubb MH, Bostock J, Rogers J and Rosenthal E. Twenty-Seven Years Experience With Transvenous Pacemaker Implantation in Children Weighing <10 kg. Circ Arrhythm Electrophysiol . 2016;9:e003422.

7. Clark BC, Kumthekar R, Mass P, Opfermann JD and Berul CI. Chronic performance of subxiphoid minimally invasive pericardial Model 20066 pacemaker lead insertion in an infant animal model. J Interv Card Electrophysiol . 2020;59:13-19.

8. Clark BC, Opfermann JD, Davis TD, Krieger A and Berul CI. Single-incision percutaneous pericardial ICD lead placement in a piglet model. J Cardiovasc Electrophysiol . 2017;28:1098-1104.

9. Kumthekar RN, Opfermann JD, Mass P, Clark BC, Moak JP, Sherwin ED, Whitman T, Marshall M and Berul CI. Minimally invasive percutaneous epicardial placement of a prototype miniature pacemaker with a leadlet under direct visualization: A feasibility study in an infant porcine model. Heart Rhythm . 2019;16:1261-1267.

10. Kumthekar RN, Opfermann JD, Mass P, Clark BC, Moak JP, Sherwin ED, Whitman T, Marshall M and Berul CI. Percutaneous epicardial placement of a prototype miniature pacemaker under direct visualization: An infant porcine chronic survival study. Pacing Clin Electrophysiol . 2020;43:93-99.

11. Hopper AN, Jamison MH and Lewis WG. Learning curves in surgical practice. Postgrad Med J . 2007;83:777-9.