Hi Clay,
Good question which brings up the issue of using a DeMRI for pre-screening prior to AFIB ablation. Certainly, a preliminary DeMRI as you apparently have had is good to see that is shows both atria with essentially zero fibrosis/scarring on MRI which is very likely a good sign you don't have much, if any, atrial fibrosis to speak of. But DeMRI is still quite controversial as a method for accurately detecting atrial scar.
This, as opposed to Venticular scar detection where the muscular ventricular walls are very thick and thus ideally suited for DeMRI scar detection. However, many MRI experts counter that the atrial tissue is too thin for DEMRI to accurately distinquish between true fibrotic scar and imagining artifacts. It does give a rough indication of presence of scar. However, trying to assign things as fine-tuned as 1% variations in scar many MRI experts say is just not possible with current tech inspite of what one center who has been pushing requiring DeMRI with a proprietary algorithm as a necessary pre-screening tool prior to any AFIB ablation to screen people with too much scar away from ablation and offer them only medical management of their AFIB.
I strongly disagree with that approach even when assuming for the sake of the debate over its true utility that DeMRI screening of atrial scar is just as accurate as its promoters imply.
The developing group for this concept at Univ. of Utah ( not to be confused with Intermountain Med Center AFIB group) created the controversial Utah IV system. It's not the active gradations between the four Utah fibrosis burden classification stages that is controversial, but rather the interprtation and recommended actions recommended for these Utah stages that have come under considerable critical scrutiny, especially controversial is their Use of Utah IV stage not as a referral tool to direct these more advanced fibrotic patients to only top volume persistent AFIB ablation centers and their highly experienced ablationists. Instead Utah IV is interpreted to be an exclusion tool to deny patients with significant fibrosis from ever having the chance from benefitting from even an expert ablation process see the Utah system become codified as official ablation guidelines and possibly adopted by insurance companies to deny advanced patients anything than being shuffled off to the ice flow with the elderly Eskimos parked on a lifetime of rate control and OAC drugs with nearly zero chance of ever seeing long term NSR again.
Alas, the premise of this extreme Utah IV Implication as a clear denial of ablation tool, simply because statistically more advanced afibbers are much less likely to be one and done at 1 year following a
SINGLE standard PVI, and also based on the fact that the group of studies used to derive this draconian ablation qualification model, don't seem show more than very modest gains on average by going to these same mostly moderately experienced EPs over and over again who, for the most part, are limited to just repeating the same minimal anatomical-only ablation protocol whenever these advanced afibbers require any follow up ablations.
This in dramatic contrast to including real world RCT results of combining an advanced Non-PV trigger detection/-ablation protocol to an extended PVAI index procedure, including when often needed in such advanced afibbers one to two max additional limited touch up procedures in order to acheive a very high percentage of long term freedom from all atrial arrhythmia.
I really got steamed when I first read that Utah classification system and it was clear that it was being proposed as a way to make a largely redundant and expensive DeMRI scan (rough average of $5,000 added to an already expensive procedure), as a prerequisite before anyone could qualify for an AFIB ablation!!
We're the Utah IV stage classification to become a requirement to qualify AFIB ablation patients, it would prevent folks like me and so many others on our site who are now enjoying long term freedom from all AT, or at least greatly reduced AT burden, from ever being offered an expert ablation based on the assumption that since folks like me with more advanced AFIB are likely to need more than one simple PVI to get long term freedom so why bother as it's more cost savings to just stash us all medical management and 'get used to your gradually progressive AFIB except in more rare cases that can make some hardware with dedicated lifestyle risk reduction too without ablation)
Keep in mind, that every single ablation using an EAM (electro-anatomical mapping system like Carto-3 or Insite) automatically will detect the degree of atrial fibrosis and scarring at the beginning of each ablation with a universally accepted gold standard accuracy at measuring atrial fibrosis/scarring in any event. And all without having to burden the whole cost structure with another $5,000 or more when incidental expenses are factored in to do a preliminary non-invasive DeMRI a few days before any ablation.
The only possible advantage of screening every patient in this way is to be able to steer those with more advanced disease to more experieced persistent AFIB ablationists and insure that the majority of zeros doing ablations on the side while primarily keeping their doors open doing ECVs, TEEs, pacers, ICDs, CRTs and some CTI flutter or SVT right sided only rather simple and quick ablations ... Basically doing the whole gamut of EP procedures, but who do not command come close enough in volume of AFIB ablation
to really advance their skill and craft much beyond decent proficiently with an anatomical-only AFIB ablation protocol.
Would not all that time and money needed to do an MRI that every EP will get an even more valid answer about the degree of fibrotic scarring any patient has from their EAM mapping before they start the actual ablation lesions in every ablation in any event be sufficient? And would not all those resources be better spent to better train a greater number of EPs in how to safely and with greater efficacy perform the more advance 'expert ablation protocols' so that far more can actually treat most every patient that might come through their doors, and not be embarrassed by suddenly finding themselves over their heads too often when a case that seemed like it might well fall within their comfort zone suddenly turns out to be more complex than a simple cookie cutter 'get in, circle the veins, and get out' anatomical ablation they were hoping for??
And it's a total travesty to suggest using UTAH IV as the 'go/no go' ultimate screening tool for cutting every advanced Afibber off from their chance at real freedom, or at least a dramatic reduction in AFIB burden, by a one, two or three step expert ablation process in the hands of a highly skilled advanced ablationist.
Utah IV, if any utility whatsoever, should be used to immediately refer said patients with that degree of atrial structural changes to the most highly experieced Advanced ablstion EP and center in their region who does a majority of such cases as their prime workload every day.
But why bother with the up front MRI in any event, as most EPs have a pretty good idea just in their own screening process already who are likely going to be the advanced cases and discriminating between those who have high odds of getting good outcomes with the more basic anatomical-only approach. Doing this kind of extra DeMRI screening would mostly be a windfall for the MRI companies funding much of this research, as well as the developing/promoting centers getting large good notoriety and increased flow of grants to continue trying to increase MRI's use in catheter ablation.
Don't get me wrong, I'm all for the research and it's all good to try to press the edge of what we know, but when we start having to create scenarios and justifications for adopting such a largely redundant process that already exists in our standard ablation process, when there are more sensible and effective means of gathering the same information and insights already built into the cost of every ablation, then trying to manufacture such a need starts looking a bit like an effort to fit a square peg into a round hole for the purpose of shoe-horning a role in the AFIB space for MRI tech (which no doubt the MRI makers are all excited about as would be the center and leaders of the effort that are hoping to see MRI scanning florish in this area where it has had limited utility up until now. And these days many of the docs helping develop new tech also wind up gaining big windfalls from large stock options, sale of patentable ideas and bonuses ... and nothing wrong with that for their hard work for sure.
But we first have to ask, just what utility is use of an existing tech like MRI in a new way going to provide a NET new benefit to both doctors and patients alike? And is there any potential for abuse of the technology even if the misuse, as in this case in my opinion, is mostly from creating an inappropriate use of Utsh stage IV as an ablation exclusion tool.
There are times when a DeMRI for atria visualization may well be warranted, but adopting this proposed Utah DeMRi fibrosis classification system as a standard screening tool for all ablations, seems the very definition of a red herring to me. And also apparently to a lot of EPs and hospital cost screeners as well as evident by the limited broad scale adoption of DeMRI screening before all AFIB ablations now even after the last four years of studies mostly originating from one overseeing center that processes all the properitary Algorithmically-adjusted DeMRI data in-house, even when the MRIs themselves were done in other centers as well.
At the very least, if they would redefine Utah stage IV to mean only that such patients should be referred to expert persistent Ablation centers, rather than excluding these patients from ever benefiting from an advanced ablation process, that would be a good start in the right direction in my view and I would have far less objection than I do now to the current language used in the Utah clasification system.
Myself and so many others on our website and forum have benefited so greatly from an advanced expert ablation processes of from 1 to 3 procedures, but who would easily be listed in Utah class III or IV and thus strongly discouraged from ever having an ablation at all! That is what makes me as steamed as a poached egg about this Utah system as originally defined.
It appears that since the first two Utah stages, and even the third Utah stage to a degree, are clearly redundant to EAM mapping, it thus would be hard to justify the investment of new MRI resources dedicated just for AF ablation prescreening, so the interpretation of Utah IV as an actual ablation exclusion tool would serve to really save the hospital a fair larger amount of money from simply denying these patients even referral to more advanced top volume centers who specialize in successful treatment of these cases every day.
The logic of the current inappropriate (in my view) Utah IV interpretation is based on the observation from looking at studies of mostly PVI-only experience that not only is such a single limited index ablation procedure not enough for high degree of long term success in more advanced patients, but that just repeating the same basic PVI-only or PVI plus posterior wall isolation-only follow-up procedures when recurrences occur over and over, only buys a little bit of added success long term. So why not use Utah IV to deny this group a chance at freedom from AT (all atrial tachyarrhythmia) and save at least most of advanced patients and doctors the frustration and time needed to redo the same exact expensive repeat procedure repeatedly, only to gain incrementally just a little improvement on average in the bargain?
The problem here is the skill of the EPs and/or the scope and effectiveness of the ablation procedures offered in the referenced studies used to build a case for Utah IV. And that it does not account for what is really possible in elite level persistent Ablatuon centers like Natale's groups, Bordeaux, Univ of Penn and others.
Finally, keep in mind, too, next time someone tells you you need a preliminary added DeMRI scan of your LA and RA before getting an AFIB ablation, that all they will learn will already be clearly seen in the beginning of your ablation anyway, and just by choosing the most experienced EP who does mostly advanced cases to begin with this whole debate instantly goes away!and you don't have to worry about possibly getting stuck with either a greenhorn or just a moderately experienced ablation EP who has yet to master Non-PV trigger detection and ablation beyond just the anatomical only PVI plus posterior wall isolation at best.
Roughly 9% of persistent and LSPAF cases ONLY have active drivers of their AFIB/AFlutter coming from their LAA and no where else in either atria. And since LAA tissue harbors almost zero fibrosis to begin with and no amont of MRI prescreening will confirm that you can get by with an anatomical-only ablationist. To a much lesser degree, the same is true for even basic paroxysmal cases who occasionly have Non-PV drivers in the coronary sinus and LAA as well as in the PVs and posterior wall, essentially guaranteeing such patients endless repeat ablations required unless, and until, they wise up and partner with a highly experienced advanced ablationist who does most only advanced non-PV trigger-based procedures in their daily practice.
Just some food for thought when considering if undergoing a DeMRI is a necessary step at all. Certainly, for those here who have already gotten the mantra about choosing the very best and most experienced ablatiomost they can possibly arrange for themselves, there is no need at all for such an added procedure at DeMRI and an hour slid heat first in most Tesla 2or 3 machine in those rather snug torpedoe tubes many of these high powered magnet MRI machines still have.
Be well,
Shannon