FIRM Ablation for Atrial Fibrillation on Unfirm Ground

[www.medscape.com]

As Dr Natale basically told me told me one hour before his magic hands touched my heart, he's seen no secret sauce of the FIRM procedure:

These findings, from a center famous for cardiac mapping, gives credence to one of the main arguments cited by skeptical European doctors—that the secret sauce, the black box of Topera, is a flawed algorithm.

McHale

Thanks for posting this John - I was reading it yesterday and it seems to be the source of the rumblings I'm hearing about FIRM.

BUT, Topera and Narayan (and therefore Abbott Labs) are claiming a 78% first time success rate with "FIRM guided therapy". Abbott is apparently extremely conservative in what they put out there, so there appears to be a big disconnect somewhere.

I understand that many EPs including Natale feel like FIRM is not proven. Proven or not, if they are actually showing ~80% first time success after a significant amount of time its a big improvement.

So who is right?

That's consistent with what Pierre Jais had to say, specifically with respect to the size of the blind spot when using basket electrodes. Jais says 40%, the Dutch says more like 55% so in general agreement. Even if the FIRM concept is valid, ie stable rotors, basket electrodes aren't going to get you there. Jais and Haissaguerre have already shown in their videos that the non-PVI rotors drift around. Abbott bought Topera and last week Medtronic bought Cardio Insight. I think the Cardio Insight vest is the more useful mapping tool since it is non-invasive and doesn't have blind spots.

Is the size of the blind spot related to the duration that the fibrillation is sustained during the procedure?

No. it is due to the mechanics of how the splines work, electrode placement and the shaft. Basically, you lack electrodes at the poles, the shaft end and the tip end. And then the navigation is limited since has to be placed via transseptal puncture.



Edited 1 time(s). Last edit at 06/24/2015 02:58PM by researcher.

Thanks researcher.

Is the Cardio Insight vest being used in the U.S.? I've only seen it menioned with Haissaguerre.

Both Topera (FIRM) and Ecvue (Cardio Insight) are FDA cleared. I believe the Germans have their own version and Kuck is testing it. Ernst in the UK is playing with it too. I don't know who is active in the US. Since it originated out of Cleveland Clinic research, I would think that is the more obvious place to start. With Medtronic owning the technology now, I expect it will spread quickly, just as they were able to do with Cryocath arctic front after they purchased that.

researcher Wrote:
-------------------------------------------------------
> Both Topera (FIRM) and Ecvue (Cardio Insight) are
> FDA cleared. I believe the Germans have their own
> version and Kuck is testing it. Ernst in the UK
> is playing with it too. I don't know who is
> active in the US. Since it originated out of
> Cleveland Clinic research, I would think that is
> the more obvious place to start. With Medtronic
> owning the technology now, I expect it will spread
> quickly, just as they were able to do with
> Cryocath arctic front after they purchased that.

In that case I have been benefiting from Dr. Ernst's 'toys' . DSPECT which is mapping GP's before ablation(radionuclide scans using DSpect camera merged with contrast CT scan to give a 3D image of the GPs. Les

Les, I didn't realize you got recruited into the GP/DSPECT trial. I would be interested in seeing your full report if you are willing to share. I hope that it was a benefit for you but then trials are done to see if there is a benefit over standard of care. You were probably a more challenging case in the spectrum of cases given the unexpected size of your LA. The idea of GP ablation has been around for about 10 years now. Warren Jackman's group did the initial research on it. DSPECT finally has the tool to try to map them. There are two issues as I see it, the ability to map them and the ability to get to all of them endoscopically.

[clinicaltrials.gov]



Edited 1 time(s). Last edit at 06/25/2015 01:41PM by researcher.

ClayS Wrote:
-------------------------------------------------------
> Thanks for posting this John - I was reading it
> yesterday and it seems to be the source of the
> rumblings I'm hearing about FIRM.
>
> BUT, Topera and Narayan (and therefore Abbott
> Labs) are claiming a 78% first time success rate
> with "FIRM guided therapy". Abbott is apparently
> extremely conservative in what they put out there,
> so there appears to be a big disconnect somewhere.
>
>
> I understand that many EPs including Natale feel
> like FIRM is not proven. Proven or not, if they
> are actually showing ~80% first time success after

> a significant amount of time its a big
> improvement.
>
> So who is right?


ClayS, that figure is INCLUDING A PVI/PVAI and the quoted result are not appreciably different from the results that experienced PVI/PVAI-only operators get with paroxysmal cases alone.... Take with a grain of salt what the financial promotors of a system claim ... look instead at what the bulk of respected large center independent operators are saying from their own now extensive experience with any new and as yet unproven system.

You also need to carefully parse through and examine closely the patient selection process used .. for example... such that one arm of a study is not using a large number of long standing persistent AFIB cases with large left atriums and sleep apnea in comparison to the favored arm of the study that has a somewhat greater number of easy paroxysmal cases with small left atriums and younger overall age to pump up the numbers a little bit in their favor. (okay, Im exaggerating a little for emphasis here .. but only slightly an this kind of thing in a bit more subtle fashion happens not infrequently). Even a very subtle shift in the patient selection process can impact the relative weight of how a give side of a comparative study and appears.

I have no idea what scenario and studies Topera and Abbott used to come up with those stats and they may well be pretty accurate as they are well within the range of a good quality PVI for the right patient groups and I would expect at least some improvement in the PVI + FIRM group if nothing more than simply from addressing additional non-PV targets.

But in a couple of the early comparative studies when the initial FIRM fervor was being promoted the PVI-only wing of the comparison were absolutely abysmal level results bordering on something you might expect with the three stooges behind the catheter in the PVI-only arm of the study that was then compared with the PVI + FIRM group which had very good results, not surprisingly, and those numbers were likely pretty accurate too. I found it disingenuous and unnecessary to use such a poor range of PVI-only results to try to make their comparison as the PVI + FIRM still would have looked pretty good had they used more real world and higher quality PVI/PVAI results from a top center as well for comparison.

That really raised a red flag for me about being a bit more cautious when evaluating data around this system at the time.

But the main point gets back to what I emphasized earlier which is our long standing recommendation NOT to fall in love with any given technology or mapping system or catheter etc... Instead the wise AFIB patient will make their number one priority to choose the very best, most experienced ablationist who is widely respected across the country and world, if possible, and then trust that by choosing such an elite level operator who is constantly busy doing nothing else but AFIB/Flutter ablations and has referrals from other EPs all over the US and beyond, that they are fully capable of making the best technology choices on your behalf for your given type of AFIB and for the kind of procedure you might require, and the put your trust in that.

This is a FAR FAR wiser move in my view than getting overly enamored but some press reports and hype machine and then making the technology, mapping system, catheter or whatever, the main priority such that the EP becomes secondary as long as he will use your new favorite tool, though the patient personally likely has zero experience with any of those tools. You see what Im getting at?

If you first selected an ablationist you really like and trust and their experience level and track record makes you feel confident AND he or she said you are a good candidate for them to use a PVAI +FIRM ablation.. then fine .. go for it! The take home message from all of this discussion, and underscored from all the results Dr John thankfully shared in his new report on the rather disappointing FIRM-only results, is that just make damn sure it is not a FIRM-only ablation your are signing up for.

You may, or may not, get some added bonus from the added FIRM portion included with a solid PVI/PVAI, but as long as the EP is highly skilled and consistent with a PVAI/PVI and does a thorough job, the odds are very good for a fine outcome, especially if you don't have persistent AFIB with a somewhat enlarged LA as well.

Cheers!
Shannon



Edited 1 time(s). Last edit at 06/27/2015 01:14AM by Shannon.

Shannon,

Many thanks for your perspective. I was diagnosed in 2011 so when I started doing ablation research FIRM seemed to be the next best thing. My regular EP quoted me the 50-60% success rate that you generally see so I've been laboring under the impression that that was still the standard. I'm in Indy so talked to Dr. John Miller, who was/is on the FIRM development team, in February. He quoted an "80%-ish" first time success rate, but it was also clear that he is doing PVI/FIRM, not FIRM alone. I haven't talked to anyone who has had a FIRM only procedure - I think it is seen as an adjunct at this point and a way of identifying additonal hot spots that would be missed by PVI alone, so as you say it should provide a boost in outcomes over PVI alone. I haven't postponed anything waiting for FIRM - I'm on my first med, thankfully in NSR (but tired...) and preparing for the next step, if and when it comes. After reading all the stats I don't want to wait until I'm full-blown persistent.

So long story short, I'm going to be making a call to Austin soon.

Smart move on redoubling your effort to improve mineral relpetion but also not to wait too long when the former steps don't prove nearly totally effective and thus don't delay hooking up with the Man in Austin and getting the key elite level ablation process wrapped up too.

Once it becomes clear that it's almost certain you need to complete a top tier ablation process as a central part of your long term AFIB control program. It makes no sense at all to continue horsing around rationalizing about this possibility or that ad infinitum while underlying progression almost undoubtedly continues to become better entrenched.

The problem is you'll only ever realize that you truly DID wait too long after the fact ... when it becomes abundantly clear that your own best interest required an earlier visit to Dr Natales EPLab (or what ever top tier EP you choose), it's still not too late to act if someone dies overly procrastinate (me being Exhibit A on that count) and achieve a great long term outcome, but you may well have made for a significantly more challenging road for both yourself and for Dr Natale too...(ditto me as Exhibit A once again on this later point). We don't need anymore like me having to be living examples for other folks like yourself in the future where you can freely chime in with your own war story of how you shoulda jumped a year or two earlier than you did etc...

I'm sure you'll make the best decision for yourself Clay and we are all wishing you all the best and soon to return to permanent NSR!

Shannon



Edited 1 time(s). Last edit at 06/29/2015 10:33AM by Shannon.

Oops! I had made a small edit to the first longer reply I posted some days ago in my impression of the latest FIRM
news out of the European Heart Rhythm Conference meeting from last week when it looks like I inadvertently deleted the whole message... Anyway, the first reply to Clay pretty much sums up the main points and no time to recreate the other one ...

Have a nice Sunday everyone!

Shannon

I was searching for something else and stumbled upon the following regarding GP ablation (using Botox) as an adjunct to open heart CABG. It is germane to Les with regards to what his EP tried to accomplish. Japanese researchers did a similar study in heart failure patients undergoing open heart surgery, using cryo and not Botox.

[www.medpagetoday.com]