Kaiser Northern California - 90% single procedure success rate

I find this amazing coming from what I would consider a non top tier program. In the article, they refer to "early" AF cases so this would presumably be paroxysmal and folks that are just several weeks into persistent. Everybody is getting better at AF ablation. I don't know how big a factor the magnetic navigation system (Niobe) plays but it probably helps significantly. This is very impressive for any hospital chain, HMO, PPO and all.

[lookinside.kaiserpermanente.org]



Edited 1 time(s). Last edit at 03/10/2016 06:45PM by researcher.

Hi researcher,

Certainly, there has been a notable improvement in ablation outcomes in the last couple years with the contact force catheters and continual advances in robotic navigation systems. And in Austin last week during two live ablations with both the Hansen system and Stereotaxis Niobe newer generation robotic catheter guidance systems, these improvements were emphasized showing the significant help they can give toward getting more consistent results with many EPs, especially so with less experienced operators and also with combined contact force sensing used as well.

However, I'm always a bit skeptical of a blanket hospital chain or medical centers claims of something like 'around 90% success' when so little criteria are spelled out that define said success, and with little to no studies referenced, especially no randomized control trial studies from a particular center making those claims and helping to validate the results. Typically, ablation success refers to one year freedom from AFIB off all AAR drugs, but too often the numbers do not include freedom from all atrial tachy-arrhythmia such as left and right atrial flutter or tachycardia ... just for no AFIB itself, and from some such reports it can be 6 months or less follow up and also include AAR drugs to pad the stats a bit especially in a promotional piece like the one above.

In addition, such not so well-defined stats often lean heavily on carefully chosen patient selection criteria too, as this one at least implies it does with the caveat of the claimed success being applicable only to 'early cases' which, as you noted above likely include just truly straight forward garden variety early stage paroxysmal AFIB and perhaps some scattered percentage of early months persistent cases.

However, usually such screened cohorts being used to pump up the results claims typically include only those meeting those two criteria who also have smallish left atrial diameters as well which also strongly helps stack the deck for more rosy outcomes than would be true when a more random cross section of all consecutive AFIB patients who came to a given center for ablations.

When reading so many reports and studies on AFIB in search of those with good reliable data behind them, I'm often struck by the rather loosely defined criteria used when success rates are being claimed.

That being said, I've no doubt too that as you noted as well researcher, overall the good news is that ablation outcomes are indeed improving significantly over the last couple years relative to prior years, particularly from more active ablation centers, both from improvement in catheter designs including the advent of CF catheters and improved mapping, as well as with advances in robotic steering systems. Further major improvements will certainly show up in the next few years too from the big jump in EPs and smaller centers finally starting to look beyond doing only PVI alone and learning how to do Non PV trigger ablations as well.

The reader should just be aware of the wide ranges of real criteria being used when quoting such stats, and thus take with a fair grain of salt such numbers quoted in particularly a promotional setting or venue. It's not that the quoted outcomes are necessarily false, but that by carefully sliding the goal posts for determining success and blurring the lines a good degree with such non-randomized reports and thus gild the lilly in ways that don't necessarily reflect a given centers real world outcome over time with consecutive all-comers being ablated in a given broad category of AFIB patients.

That's why we have to be very careful in trying to compare success results from the large high volume centers who have the research departments to more accurately track outcomes and whose patient case load include a majority of more challenging persistent and LSPAF cases that typically report on consecutive cases of the same kind of AFIB being studied over time that were ablated at their center, compared to only what sounds like great numbers from other centers who may well be cherry picking using more idealized and carefully selected subgroups of Afibbers to reflect their results in the best possible light.

A 75% to 85% two procedure success outcome over two years follow up from a more reliable high volume center looking at a large majority of persistent and LSPAF cases is far more impressive and reassuring than 90% single procedure claims from a center following only selected easy patients over an undeclared time frame and not making it clear what all entailed their definition of success.

I wish it wasn't so hard to sort out the wheat from the shaft here, but when marketing and big dollars are involved it seems to be more the norm for than the exception , especially for smaller or less high volume established centers trying to gain traction and reputation in a given technical field for them to find clever ways to pad their results as much as possible while not actually being outright deceptive about it. It forces us lay consumers to have to learn to dig deeper and read the fine print before reaching an accurate assessment of the claims.

Shannon



Edited 3 time(s). Last edit at 03/11/2016 03:52PM by Shannon.

I have emailed the department there in Santa Clara and ask for clarifications regarding single procedure 90% success rate and overall success rate including more complex AF cases. I will post response if I get one.

Here is what the Kaiser Santa Clara EP department sends out to ablation patients as of 2 years ago -

[mydoctor.kaiserpermanente.org]



Edited 1 time(s). Last edit at 03/11/2016 03:49PM by researcher.

Shannon, With regards to CF catheter ablation, below some data comparing the different modalities. If one is good at it with SF, CF does not seem to add much based on current data. (See figures 1 and 2). As Vivek Reddy said though, CF certainly makes a difference for those coming up on the learning curve and he insist on fellows using CF.

[onlinelibrary.wiley.com]

Good idea researcher to ask for the specifics behind that new claim, will be interested in any data and quality thereof that you receive.

And thanks for the link to Kaisers two page overview summary of AF ablation which is a quite good overview I feel, though rather general in nature and we don't know if these are specific stats from the full Kaiser network or specific center or just using the overall stats that are so often quoted from the larger studies from the top volume centers that so many centers and operators that do not necessarily have robust research departments for AFIB like the few most high volume centers do, and thus might simply borrow the published stats on success rates from the elite center studies and report those results to give an indication for prospective patients of what the state of the art in the field is at the time.

Whether or not the actual stats apply fully to their own experience over the past years is not possible to glean from that summary, but they sound reasonable overall. Note too that the 75% to 80% claim success is for paroxysmal-only cases over two years follow-up which, by definition, also includes any follow up ablations during that two year span which makes the numbers more reasonable for a medium volume center. What we don't know is if their average number of total ablations for Paroxysmal-only patients over the two years is closer to 1.2 to 1.3 total ablations over two years as is typical for the more elite level centers, or perhaps closer to 1.8 to 2.2 and even higher total number of procedures over the same follow up time frame for progressively lesser experienced and more limited operators over a similar time span needed to achieve those decent results, or better.

And to their credit they clearly note that success rates for persistent and even worse case for LSPAF, are significantly lower and their rather optimistic quote at the time two years ago (and until recently this last fall) of 50% success for LSPAF which was the most robust Catheter ablation results published for LSPAF ablation until the Natale multi center groups ground-braking randomized control BELIEF trial presented last September in London at the large annual ESC congress showed a very impressive gain in two year success rate with 100% LSPAF cases in a rigorous RCT in which all of the cases had either moderately large LA diameters of (47mm to 49mm) to severely enlarged (above 50mm for a large number of the cases) and yet this group of LSPAF ablation cases had overall two year success after an average of just 1.2 ablations of 76% which included no atrial tachy-arrhythmia of any kind at two years and off all AAR drugs.

This was achieved using Natale's extended PVAI plus Non-PV trigger protocol plus adding empirical LAA isolation to the designated LAA isolation arm of the comparative RCT study to achieve this huge jump in efficacy for this most challenging class of patients to treat ser summary is a rather good boilerplate overview of AFIB treatment circa two years ago. However, we just don't know if that truly reflects their own in house numbers or is mostly collected from other larger high volume center RCTs done previously and elsewhere.

Its an accurate overall account very much like many of these 'AFIB Ablation 101' summaries seen on many EPs websites whether they are low to modest volume or high volume operators, so it's hard to be sure how much of those results truly reflect the person who might be the one you are considering hiring to put their hands on your catheters at such a center, and how much might be a mostly borrowed reflection of the best on average that state of the art AF ablation has to offer at that time. Without knowing that the stats are from the center one is looking at, rather than perhaps largely borrowed from elite high volume research centers, it's just hard to know for sure.

That's why we typically urge people, if there is any doubt, to take whatever steps they can arrange to put themselves in the hands of an operator who they know has a large volume of confirming history behind them. Not that others can't also do a great job for you too, but just to stack the odds in one's favor from the outset if at all possible.

Shannon



Edited 1 time(s). Last edit at 03/12/2016 05:39AM by Shannon.

With regards to the first post and subsequent inquiry to Kaiser regarding details, Dr. Charles Young responded through the author of the article.

From Dr. Young -
"The 6 month success is what is typically published in the literature and is generally lower than the 2 year success as late recurrences do occur. Our 6 month success rate that was mentioned in the article pertains to a select group of patients who have early paroxysmal atrial fibrillation and as a group, generally have better results across all centers. For these patients we use Cryoballoon ablation and the near 90% success rate refers to just this group. The break down of success for the other more complex AF patients who undergo RFA with stereotaxis guidance in our practice is generally lower depending on how persistent their AF has become. The article was not meant to be misleading but some the limitations on the format and target audience may have made it less clear towards the specifics."

This is good information as several have asked in the past about Kaiser ablation services. Their preferred tool for paroxysmal AF is cryoballoon ablation and they try to catch the patient while they are still in paroxysmal AF. That is a smart strategy for both patient and HMO as it minimises burden on both assuming they have found a way to reduce phrenic nerve injury to an acceptably low level, something that is of concern with cryoballoon usage at less skilled centers.

Thanks Researcher for asking for a clarification from Kaiser.

It does seem too that Dr Young was making a good faith effort to answer you inquiry and clarify the circumstances in which that 90% success claim is framed.

One thing that jumped out at me and which might well be just a slip of the tongue (so to speak) is when Dr. Young said 'The 6-month success is what is typically published in the literature and is generally lower than 2 years success as late recurrences do occur." I think he meant the reverse: ... that 2 year success rates tend to have 'lower' success rates compared to those shown at a 6-month follow-up point after the ablation in the same population group being followed and not vice versa as he indicates in your quoted excerpt of his response.

Perhaps Dr. Young may have meant to convey the reverse message. It's certainly true that the early 6 month result from most any ablation cohort will show the best looking success numbers at 6 months as compared to at 24 months when following the exact same group. Unless he is accounting for the final results at 6 months after including any and all follow up ablations to address any breakthrough arrhythmias during that 2 year period?

It's true too that some centers like to state their 6-month results as representative of their ablation success outcomes because those earlier results most often tend to reflect the better case success scenario across the total number of ablatee's being followed over time.

In his report to you did Dr Young indicate whether that 90% is limited to just freedom from AFIB alone, or does it also include freedom from all post-ablation tachyarrhythmia such as right or left atrial flutter or atrial tachycardia?Also, did their stats also possibly define whether those numbers included freedom of AFIB or all arrhythmia and off all AAR drugs as well in determining success?

thanks again for asking for the feedback researcher its good to see them respond to you so quickly. I'm glad too to see he acknowledged the report was limited in scope and format of their general education piece on their cryo-ablation and implied their comments were of a more general rather than specific and detailed in nature to address their select target audience of potential AFIB ablation patients.

I imagine that most folks reading such an info summary outline from various ablation centers are not aware of the distinctions and nuances between early paroxysmal and persistent AFIB ablation issues and the often significant difference in outcomes and strategies that are successful in these various forms of AFIB.


Cheers!
Shannon

Shannon, I was hoping that Dr. Young would answer with additional details regarding the specifics that were not addressed, ie monitoring method, frequency, on or off AADs. I am afraid this is the best I can expect for now. It is too bad I had to go through the author and not directly email Dr. Young. I would have been able to ask more follow ups. Kaiser has huge coverage in CA and many AF patients will end up using their services so I will try to find out more in the future.

Thanks again researcher for your efforts at getting the feedback you have gotten already. That is more than most such centers convey as it is, even though as you noted it leaves a lot to be desired.

When trying to see how close those 90% success projections are to real world reality over a reasonable time frame that afibbers could bank on. It's pretty clear they are referring to just the very easiest paroxysmal patients at a best case 6 month time frame post ablation as it is, so that was valuable info indeed that you solicited from Dr Young.

Apologies for the delay in my last reply as Magdalena and I are down in Phoenix the last few days for her own radio frequency ablation tomorrow ... Gratefully not for and cardiac arrhythmia issue but it's an out patient same day RF ablation of her lifter left L3 or L4 lumbar facet joint nerve with her back doctor. This is the same nagging and relentless localized low back pain she has had for about 3 years now and that originally led to discovery of her kidney tumor ( luckily which tuned out to be benign after biopsy following her rather brutal partial nephrectomy surgery in January 2015 at MD Anderson in Houston.

That MRI was looking for the source of her lower left side back pain in late 2014 that uncovered her kidney tumor and gave us both the very intense cancer scare. Hopefully after finally pin pointing the source of her pain, this much simpler and far less invasive facet nerve ablation tomorrow will finally end this long saga for her and help her get better sleep and long term relief at long last.

Although as with the kind of RF ablations we all know so well, it's not uncommon to have to repeat this type of ablation too from one or more times to get durable freedom from the nerve pain.bee should be back home on Sunday to catch up more with posts.

Be well,
Shannon