Value and Potential of Remote Magnetic Navigation in EP: Interview with Dr. Andrea Natale

In this feature interview, we speak with Andrea Natale, MD from Texas Cardiac Arrhythmia Institute at St. David’s Medical Center, about his use of remote magnetic navigation for the treatment of complex arrhythmia. 

Describe your extensive background in EP. What are your specific areas of interest? 

I trained initially in Rome, then in Canada with Dr. George Klein, and later in Milwaukee with Dr. Masood Akhtar. My first appointment was at Duke University; after that, I became the Director of the EP Section at the University of Kentucky in Lexington, and later served as Section Head for the Department of Cardiac Pacing and EP as well as Medical Director for the Cleveland Clinic’s Center for Atrial Fibrillation. Since 2008, I’ve been the Executive Medical Director of the Texas Cardiac Arrhythmia Institute at St. David’s Medical Center in Austin, Texas. 

My areas of interest include device therapy and modality of shock therapy with different devices. In the last 15 years, I’ve become more focused on ablation, especially for atrial fibrillation (AF). 

Tell us more about St. David’s Medical Center, specifically the Texas Cardiac Arrhythmia Institute (TCAI).

TCAI employs a combination of clinicians and researchers. We currently have 12 electrophysiologists that are involved in all sorts of complex EP procedures. The primary scientists in the group work out of 9 different locations in Texas; personally, I also perform procedures in San Francisco and San Diego. Overall, our group manages a considerably large volume of ablation (both ventricular tachycardia [VT] and AF) — it’s certainly the largest volume of ablation in the western world. Our research group consists of 4 research fellows, 1 statistician, and 9 AF nurses, all of whom help with protocol, and manuscripts about the work and research we conduct. 

St. David’s Medical Center’s physicians have treated over 1,000 patients diagnosed with heart rhythm disorders with remote magnetic navigation (RMN) technology. Can you briefly describe what this unique technology is, and what has continually attracted physicians to it?

In Austin, we have access to the newest technologies available for treating VT. Most of our physicians doing VT ablation use RMN technology from Stereotaxis, because it allows them to handle the procedure in a more relaxed fashion. The manual procedure can last several hours and requires the physician to stand at the table, which can be tiring. With RMN technology, you can sit at the remote control panel and create the map. Especially in structurally complex heart disease patients who have a large scar area that needs to be addressed, we have found the map is usually more accurate with Stereotaxis. The ablator also tends to do a better job at obliterating all the relevant channels in patients with a complex large scar area, compared to a manual approach. When comparing the manual approach vs the magnetically guided approach, we have data to support the importance of magnetic navigation in patients with a large scar area. 

Many EPs focus their research on finding the best ablation techniques. How important is the human factor in managing these techniques, so procedures are more efficient, reproducible, and provide the ultimate safety profile for the patient?

It is very important, because doctors can become discouraged with remote navigation if they haven’t spent much time learning how to properly and efficiently use this technology. They also don’t realize that the way the ablation is done is completely different than a manual approach. With a manual approach, we always worry about too much power, steam pops that can potentially lead to complications, and perforation. We use magnetic navigation because it’s a softer contact. The people that have actually invested the time to become proficient with RMN and its learning curve, and addressed the differences between magnetic and manual navigation, love this technology and find it difficult when magnetic navigation cannot be used in a procedure. 

Do you believe that RMN technology would enhance these variables?

Skills are obviously a very important variable when doing a manual procedure. It can greatly affect both the outcome in terms of success and also in the potential risk of complication. With magnetic navigation, the system compensates for some of those issues. There is no need for a skillset in order to be familiar with the RMN system, so even the less experienced ablator can achieve the same result and do the same job as an experienced operator, because the system can account for that. It makes a difference once the operator goes through the learning curve in homogenizing the result and making the results similar in the end for people with different skillsets and experience. 

You were recently appointed the Global Principal Investigator for the Stereotaxis MAGNETIC-VT randomized controlled trial.  Can you describe this study?

MAGNETIC-VT is a multicenter global study, with participating centers in the U.S. and outside. In this study, patients with ischemic scar VT are randomized to a manual vs magnetically guided ablation using the Niobe® ES system. The idea came from some of our retrospective data suggesting that magnetic navigation might result in an improved and higher success rate than a manual approach, likely due to a fatigue factor in the manual approach. Based on that retrospective information, we wanted to address this issue in a prospective, randomized study that would ultimately give a clearer value to these findings.   

We currently have confirmed 10 participating centers and will expand into more centers, with over 300 patients. The trial should take about 2-3 years. There will be a 2- to 3-year enrollment period, and once all patients are enrolled, we’ll do at least a 1-year follow-up on all of them. 

You recently said that provided that the RMN ablation arm shows statistically superior outcomes to the manual ablation arm, this would further prove that RMN is the standard of care for VT ablation. Can you elaborate more on this? Would this impact how VT should be treated?

The retrospective data we have suggests that the magnetic approach can be superior in patients with post myocardial infarction VT with a large scar. If we can validate that finding in a prospective, multicenter, randomized study, this approach could become the gold standard for this particular group of patients, and that is important. 

The Journal of Cardiovascular Electrophysiology (JCE) recently published a dedicated supplemental issue on RMN, with you being one of the Guest Editors. How would you assess the role RMN could play in a broad array of arrhythmias beyond VT?

Yes, we put together a series of peer-reviewed articles for JCE featuring various centers’ experience with magnetic navigation and different applications for VT ablation, AF ablation, and arrhythmias in patients with congenital heart disease. There is a group from Portugal presenting their experience on AF ablation, a group from England presenting their experience on congenital heart disease, and another group reviewing the technology in the application of VT ablation. There is also a group that has performed a multicenter nonrandomized series of ischemic cardiomyopathies, and they’re going to be presenting the result of that European study. We invited articles that evaluated different applications of this technology, and the experience gained so far with magnetic navigation. 

In general, this system can be valuable in any complex management with ablation. In patients with congenital cardiac disease, navigating in the complex anatomy of this repair can become challenging, so this is a group of patients in which the system is of benefit. The same is true in general for VT ablation. AF ablation is another complex procedure in which the manual skill of the operator is critically valuable — this system can bridge that gap and reuse the elements of that skill in the hands of less experienced people. So for the most part, the system is being used in a variety of arrhythmias, where the skill required for mapping and ablation are more relevant, and that is the group of patients where the system can equalize the difference between an experienced and less experienced operator.  

You have been on the forefront of researching and adopting innovations in the EP industry. What new ablation or mapping device(s) would you most like to see integrated with RMN technology in the future?

Currently, the system is integrated with Biosense Webster’s Carto mapping system, using a standard mapping navigation catheter. I don’t think allowing a different mapping system is necessarily a priority — I believe the most important thing that most of the people involved with magnetic navigation would like to see is the enhancement of contact confirmation technology with magnetic navigation. I think that is something that might also help the integration of this technology, because some of the operators that are less experienced with navigation might be wondering about the impact of the soft touch of this approach between the catheter and the tissue. With more objective information, these operators would feel more comfortable using this technology. So the enhancement of the catheter contact confirmation (and maybe integration of contact force technology for users less experienced with magnetic navigation) is something I would most like to see in the future.

Disclosure: Dr. Natale has no conflicts of interest to report regarding the content herein. Outside the submitted work, Dr. Natale reports consultant fees/honoraria from St. Jude Medical, Medtronic, Biosense Webster, Janssen, and Boston Scientific.