Atrial Fibrillation Focal and Rotor Catheter Ablations Show High Success Rates — Video Interview with Dr. Sanjiv Narayan About the FIRM Trial
December 12, 2011
- Summary: One of the newest frontiers in atrial fibrillation catheter ablation is focal and rotor ablation. In this video, Dr. Sanjiv Narayan talks about the results of the FIRM trial that he presented at the American Heart Association Scientific Sessions 2011.
- Reading and watching time is approximately 6 minutes
In this video interview at the American Heart Association Scientific Sessions 2011, Dr. Sanjiv Narayan discussed the high success rate of the FIRM trial of focal and rotor catheter ablation for atrial fibrillation.
View the video interview with Dr. Narayan (approximately 5 minutes):
To learn more about the eight centers performing the FIRM ablation, please see Dr. Narayan’s profile.
About Sanjiv Narayan, MD:
Professor of Medicine
University of California at San Diego
For more information, see Dr. Narayan’s profile
Mellanie True Hills: This is Mellanie True Hills with StopAfib.org. I’m at the American Heart Association Scientific Sessions with Dr. Sanjiv Narayan. He’s an electrophysiologist and professor of medicine at the University of California in San Diego. Dr. Narayan, this morning you presented some very complex and fascinating data on the work that you’re doing, the FIRM data. So would you share with us for purposes of patients understanding the FIRM data and what implications it might have for them?
Dr. Sanjiv Narayan: Yes. Thank you very much Mellanie for the opportunity. So, for some years now, my lab has been interested in trying to understand what causes, and what enables, atrial fibrillation to continue in patients. And I presented some of that work today. And, very briefly, what we’ve found, and I presented today and recently, was that atrial fibrillation is not as chaotic and disorganized a rhythm as we’d previously thought. And that, in fact, in many, if not all, patients, atrial fibrillation can be caused by one or two, rarely three, localized areas in the atrium, the top chambers, which are different in every patient but which actually cause the afib. And if you can identify them, you can specifically ablate those areas and terminate the atrial fibrillation before doing anything else. That’s basically what we showed.
More recently, in the past few months, we’ve presented a larger set of patients in the CONFIRM trial where we studied about 106 patients. And in the CONFIRM trial, we found that when we targeted these areas for ablation, which were typically about two sites in every patient, we were able to terminate atrial fibrillation, or substantially slow it, in about 85 percent of patients down to regular normal sinus rhythm. Then we did the standard of care ablation as well, which was pulmonary vein isolation.
The overall procedure took exactly the same length of time as a conventional ablation would do, and when followed for a couple of years, the patients who’d had this additional ablation, which we call the FIRM ablation, had a much higher success rate than those who had the conventional ablation alone. At two years, the freedom from atrial fibrillation was over 80 percent—it was 84.3 percent actually—in the FIRM limb compared to the conventional limb.
Mellanie: That’s fabulous. And then you also talked about taking those who had had previous ablations and, the FIRM data related to that. Can you share a little more about that with us?
Dr. Narayan: Yes, certainly. It’s always a bit of a challenge when people come back with atrial fibrillation having had a pulmonary vein isolation. In particular, sometimes you wonder whether the pulmonary vein isolation didn’t quite work, or maybe there’s another part of the heart that’s actually driving the afib in those patients, and a lot of studies have suggested that it’s the second explanation—there may be areas outside the pulmonary veins. So we explored that in today’s presentation. And in the subset of patients we found the following: that in patients that had had previous ablation, they came back and we were able to identify sources.
They were typically these areas, rotors, which are little spinning tops in the atrium, or focal beats, where electric activity spreads out—a bit like if you dropped a pebble in a pond it would spread out—and we ablated those directly. And I showed a few cases where we had terminations of afib in about a minute—one of them was 48 seconds, one of them was two minutes—very, very rapid.
Now, having done that, we were actually in this subset unable to get afib again in the laboratory. The next step would be to go and isolate the pulmonary veins, but in fact that was already done in a previous procedure, and when we checked them, on this procedure, the veins were already successfully isolated, so we basically stopped. So essentially, with a five minute total ablation time, we were able to complete the procedure; that compared to about 50 minutes in the other patients in whom we had to complete the pulmonary vein isolation. Interestingly, in this subset, when we followed them with an implantable loop recorder to show they had no recurrence, every one of them is free of afib at follow-up on about 310 days average follow up.
Mellanie: That’s great. And this was a mix of both paroxysmal and persistent?
Dr. Narayan: Yes. Actually it’s a small number of patients, but 80 percent of them actually have persistent and 20 percent had paroxysmal.
Mellanie: That’s really promising information, especially for those who have had catheter ablations previously, and they’re still not completely over their afib, so that’s really exciting information.
Mellanie: Thank you, Dr. Narayan, for sharing this exciting information with us. This is Mellanie True Hills for StopAfib.org.