Adoption of fluoroless catheter ablation may rise with proper training

Fluoroless catheter ablation, a technique used to treat arrhythmias that greatly reduces exposure to radiation, should be more widely used in the field of cardiology, according to some experts.

“The amount of fluoroscopy received by a patient during a routine [atrial fibrillation] ablation procedure is estimated to be the equivalent of the dose of radiation a patient would receive with 830 X-rays,” Bruce B. Lerman, MD, FHRS, H. Altschul master professor of medicine, chief of the division of cardiology and director of cardiac electrophysiology at Weill Cornell Medicine and NewYork-Presbyterian, said in a press release. “In our hands, the vast majority of AF patients do not require fluoroscopy, resulting in no radiation exposure to the patient or the electrophysiologist performing the procedure.”

According to Lerman, with the proper training, physicians around the country can adapt to fluoroless ablation of AF and reduce the amount of radiation patients and physicians are exposed to during the procedure.

“The most critical requisite for performing fluoroless catheter ablation of AF is a willingness to relinquish an old habit,” he said in the release. “Doing so will have a tremendous advantage for both patients and health care professionals.”

Lerman spoke with Cardiology Today about the benefits of fluoroless catheter ablation and how it can be adopted by the cardiology community for safer, equally effective treatment.

Question: Why is an alternative to fluoroscopy imaging to guide catheter ablation needed? What are the risks associated with this imaging procedure?

Answer: The major advantage of this is that it reduces the amount of flouroscopy or ionizing radiation. That's important for a number of reasons because radiation has two adverse effects in general. One is that it can cause skin erythema or laceration, but more importantly, over time it can cause malignancies and the degree of flouroscopy you receive has adverse consequences.

The advantage of doing this procedure without fluoroscopy is that it reduces the exposure to this delicarious radiation.

The reason why everyone hasn't adopted it yet is because most people, including myself, were trained in terms of using fluoroscopy and seeing images based in understanding of anatomy based on fluoroscopic images, so we all feel comfortable in doing that.

The introduction of intracardiac echocardiography, which allows you to view internal structures, but in a completely different way, makes many physicians a little more insecure about where everything is because we've been accustomed to imaging using a different modality.

Once one gets accustomed to doing this, it allows for things that were formerly thought to be undoable. Fluoroscopy for a typical AF case can be anywhere from 20 to 60 minutes. When you use that much fluoroscopy, you become accustomed to being dependent on using it and understanding where your catheters are based on that.

We often think or used to think that safety was determined to help facilitate it by the use of fluoroscopy, so this is a different modality, a different way of thinking, a different way of constructing three-dimensional anatomy in the mind's eye.

Q: How does fluoroless catheter ablation work?

A: What you do is introduce catheters into the veins in the groin area and then pass them up through the great vessels into the heart itself. Then in the heart, you have to put them into various specific regions in order to do this procedure. These are very precise areas that you have to enter, so what happens is that the echocardiography allows you to visualize the entire course of the catheter going up into the heart. It allows you to place the catheters in a proper position. Often, you have to make two punctures in the wall that separates the right upper chamber from the left upper chamber, which can be a potentially dangerous part of the procedure that can be associated with some serious consequences. It allows you to clearly visualize the plane that your catheter should be in. It also allows you to visualize the course of the catheters going from the right upper chamber to the left upper chamber, so it gives you a visualization that is very complimentary in what you see in fluoroscopy. It allows you to get everywhere that you were going before. It almost seemed improbable that it would work. But it does work, and it works quite well.

Q: Would the use of this procedure significantly impact cost?

A: No, I would say that the advantage of this is not cost savings. The advantage of this is safety to the patient and to the laboratory personnel.

Q: Are there any challenges or risks associated with fluoroless catheter ablation?

A: Let me repose your question. Are there any more dangers in using this than in using fluoroscopy? In terms of danger or in terms of where the catheter goes — forget the ionizing radiation — can you navigate the catheters as well with intracardiac echo as you can with just fluoroscopy? I would say that the answer is yes.

Q: What is the current research base on fluoroless catheter ablation? Are there any major studies to mention?

A. This is not researched. This was introduced about 5 or 6 years ago and one or two groups initially said, “Hey, you can do this,” and it didn't catch on for various reasons.

We're not the first group to introduce this by any stretch, but it didn't go very far for various reasons.

One of the groups used a different technology that's no longer around and then, for whatever reason, I don't think people quite accepted that this could be done, except by maybe one or two centers. We just gradually transitioned into this and I, quite frankly, had some doubts about it too. It just didn't seem very practical and it seemed like it would add time to the procedure — these procedures are rather lengthy to begin with. Do we really want to be adding time to something that already takes several hours? What we recognized is that with a little bit of practice, you can do this just as rapidly and safely.

To answer your question, there haven't been prospective studies that have said, “OK, we're going to do 20 patients without fluoroscopy and 20 patients with and see what the overall time of the procedure is, etc.'” Those kinds of studies, to my knowledge, have not been done or published.

Q: You mentioned that this would be effective with the proper training and your institution is educating fellows o n this procedure. W hat training is needed?

A: The training is just to become familiar with intracardiac echo. There are certain kinds of maneuvers that one uses to get certain views that are readily acquirable. Really, it's overcoming the reluctance to visualize something in a different modality. I think it's more psychological than it is anything else.

I don't think that this is technically more challenging; you just have to get over the barrier that you were trained in the one modality and then you're shifting to another. It would be like changing to the metric system. It may be a better system, but hey, I'm accustomed to thinking about feet and yards.

Q: Realistically, would the benefits of this procedure be enough to replace fluoroscopy in the future? If so, how many years do you think it will be before fluoroless catheter ablation becomes the industry standard?

A: I don't think that fluoroscopy is ever going to go away entirely. I think that we can do a very high percentage of our procedures right now with zero fluoroscopy, but we can't do every procedure. Some procedures may require 20 to 30 seconds just to make sure you're absolutely safe when there's something that is equivocal. You always want that backup that may require more than that. At the present time, I do not think that there is going to be 100% elimination. I think the laboratories are going to become much less reliant on it and it will become a supplementary tool as opposed to a primary tool.

Q: What other research is underway looking at this technique?

A: What laboratories have done is tried to apply this to probably the most complex of arrhythmias, such as AF. If you can do it for AF, then there are multiple other kinds of arrhythmias in different locations in the heart that we ablate, and they're much simpler and much more straightforward procedures than AF. Therefore, if you can do AF, you should be able to extrapolate this to almost any other arrhythmia. A number of people have shown that in simpler types of procedures, you can also do this without fluoroscopy.

We do a number of other kinds of procedures without fluoroscopy. The more important reason why we talked about AF is because that is usually the one that requires the most fluoroscopy to begin with. It's a proof of principle. If you can do it for that, you can do it almost anything else. We say that research in this regard is giving a more formal term to what people are sort of transitioning to on their own at this point. It's having each laboratory demonstrate to themselves that they can do this procedure. If you can do a fluoro-based procedure, you can do a fluoroless procedure based on the echocardiographic technology. You just have to get a little bit accustomed to that and most laboratories are accustomed and are using it, but they're using it in a different way. They're not using it to replace fluoroscopy, but to supplement it. The way I'm looking at it is that fluoroscopy is now supplementing echocardiography.

Q: Anything else you would like to add?

A: I think that this is going to emerge as most laboratories do it. They’re going to find that once people talk about it, they're going to want to try too, and they're going to find that it's not so difficult to do. Once they get used to it, I don't think they're going to go back and likely will be quite pleased with the fact that they can achieve that skill set, which I don't think is a very high bar at the present time. – by Dave Quaile

For more information:

Bruce B. Lerman, MD, FHRS, can be reached 520 E. 70th St., Starr-4, New York, NY 10021; email: blerman@med.cornell.edu.

Disclosure: Lerman reports consulting for Biosense Webster.