Hi Afhound99,
I do have to admit to being a bit disappointed in hearing some aspects of her talk at Qatar as noted above. But I dont doubt she is sincere and has a genuine interest in her patients and in learning to do the best for them. She is still an up and coming ablationist building her practice too and discovering what will work for her and I have hopes that her viewpoints will expand with more experience and research .. perhaps her current focus on GP ablation will open some of those doors to more extended ablation targets beyond just a PVI, even if she finds the GP centered ablation targets are some what of a variable mixed bag as so many others have found previously, but if she and Sonny Jackman can offer some added insights into how to target GPs as parts of an extended process beyond the PVI for persistent and complex paroxysmal cases then that will be great. The very skimpy evidence shown so far is a long way from demonstrating any kind of lasting repeatable and long term net positive impact, but Im all for the continued research there and see where it goes.
Alas, a recent RCT study that was released at Barcelona ESC recently and it has several key structural problems in the very set up of the trial, in my view, the purpose of which was reportedly to compare PVI-only to PVI+ CAFEs and PVI+Linear Lines as two well known more extended procedures beyond just PVI alone for persistent AFIB to see which method was really superior.
Unfortunately, they used a very odd and skewed allocation ratio arbitrarily allocating the 590 some odd persistent patients to a 1:4:4 allotment ratio with only 64 patients being assigned to the PVI-only group and 4 times that number to both the PVI +CAFEs (254) and PVI+ lines (250) groups, instead of dividing all three groups 'Even Steven' right down the middle three ways which is what they should have done if a common sense comparison of the three methods was truly desired. This is a good example of how numbers can sometimes result in a skewed outcome and interpretation, even though inadvertently and with well-meaning intention.
The implied rationale for using such a screw-ball allotment ratio was 'because we all expected the two extended groups to do better based on the fact that the prequel study they did a couple years ago did do better, and in prior studies extended ablation has consistently shown an advantage for persistent patients' ... so from this very weak rationale for messing with an even allocation, they automatically stacked the deck anyway in favor of the PVI-only group based on an up front assumption and bias of superiority for the more extensive methods, and thus they wind up taking a stab at what 'might' be a good guess as to the proper weighting to use! That is a real stretch fraught with possible built in inherent errors from the outset baked into the results.
Talk about skewing the game with loaded dice! If there was some other end point target other than a direct comparison of which of the three methods were really best, then just 'maybe' they would have slightly thicker ice to skate that odd ratio of assignment for each group out onto, based on such a preconceived assumption. But the main goal of this study was a straight-up comparison of the three methods to see which one had the best results inherently and what their respective risk burdens were... you don't stack the deck in such a case unless one is so focused on the minutia during set up of such a study and so intent on accounting for every little variable that they wind up over analyzing the issue and going way overboard as here, and thus missing the forest for all the trees.
The designers of this study then compounded that error, in my view, by recruiting a large multinational group of EPs from 48 mostly small to modest sized centers in most small to modest size countries ( which on the surface sounds reasonable if your main aim is to want to see the end result from these procedures in more typical ablationists hands that the average local afibber might run into in these moistly small countries, and if you are not looking for a clear example of the best possible state of the art examples of all three methods to determine which method is inherently superior when done with consummate skill). In addition, outside of the Southlake group in Canada and Dr Macles group, there were not a large number of centers and EPs recruited for these trial ablations who are renowned for a large track record of dedicated persistent AFIB ablation experience and prowess, and thus a minority fraction of the whole group of EPs doing all three classes of persistent AFIB ablations were what we would call 'highly skilled' previously in doing these more extended segments of a persistent AFIB ablation beyond just the PVI alone.
There were none of the bigger high volume world-renowned elite level persistent AFIb ablation centers or EPs recruited to perform the most challenging extended ablation methods in the two PVI+CAFE AND PVI+LINES groups. And yet, both of those extended techniques require real added skills beyond those implied in the PVI-only group that all the EPs were at least familiar with, even though with varying degrees of skill at doing the PVI alone as well.
But at least in the PVI portion of each group that was a common denominator in terms of general familiarity level among all three groups and the majority of ablationists in this cohort of EPs selected were, by definition, much more comfortable on the whole doing the PVI portion of the ablations required, than were those who were being asked to, in more than a few cases, stretch their skills and experience level to also include discovering and ablating a predefined and prescribed technique for CAFEs and Linear Lines in addition to the PVI, some of whom were doing the more extended segments for the first times.
Little wonder then that the study showed no real statistical difference for any of the three methods of PVI-alone, PVI + CAFEs or PVI + Linear Lines, yet with a slight straight numerical edge to the PVI-only group ... A result which flies in the face of a number of other previous studies, including the actual prequel stage study of this very same STAR AF I trial done a few years ago in which a smaller, yet on the whole more experienced, group of EPs with collectively a greater experience level in performing these more extended persistent ablations addressing substrate targets beyond the PVI alone, which achieved just the opposite results showing that the more extended persistent ablations beyond just the PVI alone showed a significant advantage over PVI-alone in persistent AFIB ablation which is entirely in agreement with multiple other prior studies showing the very same outcome.... and also what has been clinically found to be true time and again in real world results.
In any event, it's too bad the authors of this study in their zeal to pronounce the results a major advance in our understanding went more than a bit over the top, such that they recommend now immediate abandoning of extra PV ablation and only doing PVI alone, even for persistent AFIB, simply based on the results of this one questionable study, which is another clear example of how the bright glare of being in the spot light can overshadow good common sense and a careful analysis of what these results might really suggest ... even by very smart and well-meaning physicians.
It's unfortunate, too, that one of the key members and spokesman of the trial who was one of the more experienced ablationists with extensive ablation work as well in this STAR AF II study, did not bother to even attempt to explain why this result flies so entirely in the face of not only their very own prior STAR AF I study, which was done to demonstrate the process and baseline for the study, and which even though had a smaller overall number of ablations done, still showed the very opposite results with a statistically solid advantage of the more extended approach to persistent AFIB, that has also been confirmed by most of the well done previous studies on this topic, and also confirmed by the first STAR AF I study results as noted.
Any careful analysis of this scenario and the study structure would instantly poke some holes in these results, and at least demand more confirmation before suggesting even thinking of changing guidelines.
However, one problem that may really be hard, I can imagine, for the authors to to acknowledge and admit is that they claim this was a 'highly experience group' of EPs used to do all the persistent AFIB ablations and yet they had 48 some odd small to modest size centers used in 12 mostly smaller-sized countries (China, Canada, UK and Germany being the few bigger countries with one or more centers involved).
The majority of the the EPs involved are not from centers renowned for large numbers of persistent AFIB ablations, thus its unreasonable to expect a majority of the operators in this study to be 'highly skilled' at doing non-PV ablations during their own daily practice before joining this trial. And yet, it's no secret that AFIB ablation is a very skill and experience dependent procedure, and even though much effort is being made to make it less so with new mapping technologies and contact force catheters etc, nevertheless for all the advances so far, there is still a very steep and drawn out learning curve in this very demanding procedure, all the more so with substrate ablation beyond the PVI alone.
Why on earth did they not use say the top five to ten persistent AFIB centers in the world as their source of ablationists since, by definition, they are all experts in paroxysmal PVI ablation as well? And then allow each expert to employ, and describe in detail, the exact methodology they used for the more extended non-PV ablations that they have found most successful at the cutting edge of this field.
Then they would have had a true multi-center study using genuine experts in ALL facets of the protocols being performed, and showing real world examples of the results from best practices for each method, while eliminating the major issue of operator experience as even a question mark, especially with more challenging cases beyond the anatomical-only PVI-only portion of the procedure.
In short, what they are assuming, perhaps inadvertently, in this study is that any modestly experienced paroxysmal AFIB ablationist is fully capable of achieving the same kind of results in persistent AFIB cases as can the famous Bordeaux team, or the very few Dr Natales' of the world and some of his top protege's like Drs Lakkireddy, Pinski, Burkhardt, Gibson etc and Dr. Callans and Marchlinski at U Penn etc., and quite a few others so who are well known experts in these more extended procedures that many of these operators in this study were apparently not overly familiar with doing in their daily practices, and some not at all, prior to this study. Assuming, I suppose, they the overall results should equal that of the very best in the world simply because they gave them a cookie-cutter recipe to follow step by step for the extra-PV ablation work.
That implied assumption doesn't make much sense to me.
When looking at the centers used, in the study and the EPs there is obviously a broad mix of experience and talents, and yet it is simply stretching the mark and being a bit too generous in my view when insisting the majority of these operators where 'highly experienced' with persistent AFIB cases prior to this study. Admittedly, I hold a very high standard for persistent AFIB ablation from my own, and so many others here, direct experiences over many years.
A relatively smaller number of the EPs in this study do have a solid body of experience in such extended ablation work previously, but the majority were, by no means, 'highly experienced' extensive persistent AFIB ablationists in their daily practice with large numbers of such cases under their belts. At least not with my criteria for being 'highly experienced' in such challenging cases.
But even looking beyond the issue of operator experience per se, the limitation of a fixed CAFE and Linear lines protocol that had to be repeated exactly if any
Regardless, actual results reported in this study were quite mediocre in any event and yet a few have been trumpeting the study as proof, at last, of their 'less is more' mantra when it really shows just the opposite when honestly looking at all the variables and built in 'gotchas' in the study design.
After two procedures allowed and still 11% on AAR drugs at the 18 month mark with no more AF/Flutter or AT (atrialtachycardia) only 60% of the PVI-only group met that end point.. this includes all those who needed a second ablation and those requiring still ongoing anti-arrhythmics! Freedom from all arrhythmias at 18 months for the PVI +CAFE group was 50% with 12% still on AAR drugs and 48% for the same conditions for the PVI +Linear Lines group with 12% on AAR drugs at 18 months. Those results are nothing to write home about.
Those are not very impressive results at all, even if fairly typical for less than the top persistent AF centers including the more elite level high volume operations who do a lot more of this kind of work. But for the most experienced persistent ablationists, given two procedures for those who need a touch up in the first year, the best operators achieve in the 80% to 85% and off all AAR drugs at 1 year for even long standing persistent AFIB and a bit higher for straight persistent AFIB when accounting for the second touch up procedure when needed.
Just look at the many anecdotal reports over the years here on our site from Bordeaux and Dr Natale as reflected in the overwhelmingly positive long term outcomes from those patients just coming through our site alone who have gone to France or to Dr Natale, or selected proteges of his groups over the years, for complex ablations and who have frequented our forum for so long. These major centers have a wealth of experience and long term results over the years demonstrating the constantly evolving positive long term outcome from venturing beyond just the PVI alone when dealing with persistent AFIB.
All efforts to make those non-PV targets more effective and efficient as Dr Ernst was discussing, and that all the top persistent EPs are constantly pressing the envelope forward on, are very welcomed and these efforts are ongoing developments from Texas to France to the UK a like, and many points in between.
What this study really does, in my view, is serve is a solid confirmation of what he have preached here for years, that when it comes to persistent and more challenging long standing persistent cases there is little substitute for choosing the most experienced ablationist you can find.
In closing, though, i want to reiterate that I feel Dr Ernst is a solid EP with a very bright future in the field. This is a very challenging field and there are many new developments and discoveries yet to be made and so I applaud her dedication to the this work and appreciate many of her insights on other key issues in this field.
Yet in light of my strong support for her as a local alternative for UK patients based mostly on the input from a couple of EPs, and from reading her excellent book I purchased on 'Cardiac Anatomy for Electrophysiologist' , I now must temper that enthusiasm a bit after hearing her viewpoints on the specific topics mentioned in the beginning of this threads video clip George posted from the otherwise very interesting Qatar talk.
Primarily its just the too broad of a brush used to paint those concerns about the specific complications in what amounts to a fairly small number of ablation patients, most of whom had too many overlapping ablations over time, and the exaggerated implication that these kind of complications are found commonly in more extensive ablation process is where I have my disagreement. Hopefully that will change in the future and that I will find good reason to once again support a more open ended approval for the whole gamut of ablations done there. I will try to seek her out at the upcoming large conference in the beginning of the year and get a more nuanced impression of her views on this controversy.
Regardless though, I feel certain that Dr Ernst would be an excellent follow up EP in the UK as it is, or for doing paroxysmal ablation which I trust she is very capable and skilled at performing. She may well still be my number one choice for persistent AF in the UK if there is no way circumstances would allow a British patient to travel to Bordeaux for ablation. However, when UK patients do have the option and ability to go to Professors Jais or Haissaguerre for persistent or challenging ablation cases, that would be my strong preference and recommendation still at this time.
This reply was dictated last night into the big sized new iPhone 6 I picked up last week, and did so just before bed (BTW, this new Iphone works great with AliveCor app too), but I simply wont have time to address this issue much more until after Oct 8th to 9th, give or take a day or two, after which I will have the latest AFIB Report finished and out to press.
Shannon