When to consider ablation

I have lone afib - no episodes longer than 20 hours, most in the 4-10 hour range. They were almost daily in April, then we discovered I had pneumonia. Once that was dealt with, episodes were back to the 3-4 times/month range. I've noticed lots of folks choosing the ablation path. I could see it if I were having this for more hours at a time, every day, or nonstop. But of those who have it once and a while and not for long - have you considered or had ablation?

Nancy

I've been mulling it over and I have a date for it now.

With me I tried all kinds of things, avoiding triggers, diets, vitamins. Some worked for a while. I almost thought I had the answer when I had no AF after starting Iodine suppementation, well not for 3 months anyway. Lately it's been back with a vengeance. 10 episodes in August and 10 in September. Up to about 9 months ago I'd wait until they self terminated (which they always did, mostly within 12-15 hours). But then I started the Pill in the Pocket Flecainide approach to get rid of it in a few hours.

That was getting old. So I've been checking out the risks of an ablation, asking the doc who is going to do it, and also helped by people here.

If I was getting it once every few months I'd probably not consider an ablation. But almost every day? That's hard..

Hi Nancy,

It is an individual decision. Three to four times per month would be tolerable for some people and intolerable for others. If it is not impacting your lifestyle, that "burden" is liveable (and I say this from first hand experience; I averaged about once a week for a couple of years- when the disease progressed to every other day I had a procedure).

The disease typically does progress; however it may progress very slowly, or quickly. If you are not already taking Magnesium and Potassium, you should be, and Hans' 12 step plan is a good approach. Then see where it goes from there.

One other factor that may come into play in your decision- back in the days when I was afibbing every 10 days or so, the non-afib days were very nice, however there was always this sense of dread that it was coming back. I tried all kinds of diets and supplements; I was convinced on more than one occaision that I had beaten it, then here came afib again. After a couple of years of that, it becomes mentally taxing. After my surgery, I can go to bed at night and not have fear of awaking in afib; that, like the VISA commercial, is priceless. When you get to the point that you don't want that dread anymore, go get your rockstar EP and fix it.

Best of Luck,

EB

I am a long-term board reader and am on magnesium, potassium and you name it . Fortunately once my pneumonia was under control last spring the fibs went back to the more regular 3-4 times/month (an average some months more, others less). I HATE the fibs, but also hate surgery (I have had surgeries, not bad experiences, but one on my heart gives me pause).

Anyhow, I was wondering what criteria folks here were using, and look forward to hearing from others too. Thanks,
Nancy

Nancy how is your overall health and strength? age? I had my ablation 8/21 I am 59 and fit......at this point could nopt be happier! I will not call it a non event but almost...I had no risk/side effects, no bruising......etc....my afib was infrequent for all my 7 years....just a 3 or 4 per year but one in every 4 or 5 had to be cardioverted........in July I had 3 episodes which was rare so I gave up ........I own a natural food store and tried everything.....I was never perfect at trigger avoidance though.........I am back in the gym, feel great almost done with coumadin......but......like E B said...it's a personal decision for sure.....you must have confidence in your EP....I did........and it's not a guarantee that we no longer have afib....quite the contrary.....but honestly, I, right now do not feel like afib can happen........and of course that counts for nothing.......just how I feel.......I;ve already had a little chocolate and a few 1/2 glasses of wine............

I am on the side of ablating before it becomes really frequent and or persistant ....greater odds of success too

If your EP has done hundreds or more.......I'd feel pretty confident with regards to safety......talk to others that had ablation by him!

Tom P

Tom - the other fun is that i'm in an HMO - Kaiser. Which I adore for pretty much everything. But choice of surgeon won't really be up to me. I'm 55 and not in great health (overweight) with bad knees and arthritis along spine.
Nancy



Edited 1 time(s). Last edit at 10/01/2012 08:25PM by Nancy.

Nancy,

I also have Kaiser, and feel the same way you do, although I have only had one episode in two and half years.Knock on wood. I try & read this forum daily. I have a great Kaiser Cardiologist and EP. My EP is at Stanford two days a week. If I needed an ablation, I would be concerned about the number of ablations my EP has done and success rates. Kaiser requires that you fail an anti-arrhythmic medication (Flecinaide (sp) ) before they will consider an ablation.

I have had only one surgery in my life, the birth of my daughter so having an ablation is scary for me. A-fib is progressive, and if my quality of life was diminished, I would have an ablation. For me I'm always waiting for the next episode. Ignorance is bliss, for sure.

Good Luck.

Valli

Nancy:et
Contemplate the obesity issue, the Type II Diabetes issue and the aFib issue. It is likely that all of this is masking other afflictions. I know that in my case it was a rapid downhill spiral out of control with hypothyroidism, diabetes, weight control issues, obstructive sleep apnea, etc. etc.

End result? Asides from several weeks in hospital of which almost a month was in intensive care with my wife fighting the doctors who wanted to pull the plug on me (I survived that stupidity too). I wound up with aFib. Undiagnosed incredibly but on Metoprolol to control rate but exhibiting all of the other classic signs/symptoms. Yet amongst the five specialists I had working on me... not one diagnosed aFib. Until I was at the GP office and my wife said he is always tired and short of breath.... he is right now, 'con you do an ECG for giggles and farts?'. Well, the ECG was smack on that elusive moment that aFib was rearing its ugly head and a cardiologist spotted it.

Being in Ontario and on Ontario Health Insurance Plan, it took a year before the cardiologist got around to trying a cardioversion and he did everything exactly wrong and was so embarrassed and worried that I would chase him that he referred me, as we had been requesting for months, up to Southlake in Newmarket, Ontario and to two of the best in the world. It took another six months to get in to see them and after a simple echocardiogram they told me that my left atrium had expanded from my first visit to my cardiologist quack, where it was under 50mm, to 60mm and that an ablation was not in my cards but they had a plan. Put me on TIKOSYN and keep me in NSR come hell or high water for the same year and a half it took to expand from 49ish mm. up to 60 mm. AND hopefully we would see the atrium shrink while in NSR.

Well, it is shrinking and it is, if it keeps shrinking at this rate, going to take me another year to a year and a half to get under 50mm and into the range of left atrium size where success is a good possibility. At 60mm the chance of success is hit and miss. And they would not operate due to other risk factors that the enlargement presents.

So, if I were to do it over again, PERSONALLY? I would seek out the best as fast as possible for an evaluation and I would consider ablation as FIRST LINE treatment for aFib. I would never want to go through this again due to a quack diagnosis and treatment plan. I am so very fortunate to have caring and expertise at my fingertips now. My presents EP's do about 500-800 ablations a year between them. They have cutting edge equipment and a cutting edge facility at their disposal with highly experienced staff to assist them. It doesn't get much better than this I would think.

And again, personally, I should have sought them out right away and gone the ablation route. And if not them, then Bordeaux or another expert EP and facility.

I would never, knowing what I know today, think of anything but ablation as first line therapy.

BTW, this does not mean that antiarrhymia meds are not in the picture! Far from it. My vision of the ideal attack on aFib includes these meds before, leading up to and subsequent to the surgery to improve chances for success. Even if all you are looking for is a simple electrocardioversion to keep you out of trouble for a few months, give or take, the formula for success includes antiarrhythmia meds before, during and after the ECV, along with intelligent supplementation, especially Magnesium and Potassium.

Know what you are doing when it comes to supplementation. Magnesium and Potassium are potent - very potent. Potassium is what they use to STOP the heart of criminals being executed I gather. Mind you, a MASSIVE dose is administered. But for we aFibbers it is a godsend. I have had, in the earlier days of TIKOSYN, what appeared to me to be breakthrough aFib after eating trigger foods. A good shot of Potassium (about 1.5 - 2.5 grams) would generally shut it down, especially if I had been neglecting my Potassium intake leading up to the flip-flops. White papers read about electrocardioversion and conversion in general seems to indicate that I/V Magnesium and ensuring Potassium is in the high end of the normal range tend to help ensure a successful ECV. I never had to mention a thing. They hung Magnesium from my I/V pole immediately and checked me for serum Potassium immediately. The guy next to me started on TIKOSYN and as soon as they gave him some Magnesium he converted to NSR.

This is a complex and insidious affliction that does not want to be messed about with. It gets angrier, often without any telltales. You walk in to the best EP in the country only to be told it is a shame you did not come to see him a year or two ago when your LA was small enough to be worked on efficiently. Sic.

So, I am personally headed in the right direction (but I know now what I would have done right away) and you can rest assured that when my atria have shrunk to where the success rate is higher, I'm first in line for an ablation. No question in my mind. And as long as they tell me that I am first in line for ablation I will hold off and let the meds keep that atrium shrinking. The smaller and closer to normal in size it becomes, the greater your chances of successful ablation.

Just food for thought. Not suggesting anything more here than you take some time and read some of the studies. One I would read for sure is the one comparing ablation success to atria size. THAT was a real shocker for me.

I am now searching for ten seconds or so of aFib on an EVENT recorder to get me into a study group that will give me closer attention. And incredibly, I cannot find it. I have borrowed a portable electrocardiograph and walk around all day wired up to the EVENT record, which records the minute before and the minute after a button press when you think you are having an aFib event. And AND I am wired up to a three lead portable electrocardograph that hangs from my belt.... if I think I am feeling aFib symptoms brewing I push the button on IT and I get a thirty second strip. I can recognize an aFib or other unusual waveform from 50 yards now, but this thing is 'smart' and analyzes your waveform on the strip for various arrhythmias in ten seconds or so (much safer while driving). And THEN I push the button on the EVENT recorder to get a two minute event recording. So far, nada. Go figure. You don't want aFib, you got it. You want ten seconds of aFib, you can't find it. Just a few premature contractions or skipped beats. Sic.

Good luck to you whatever you decide. And wishing you much NSR

Murray L

--------------------------------------------------------------------------
Tikosyn uptake Dec 2011 500ug b.i.d. NSR since!
Herein lies opinion, not professional advice, which all are well advised to seek.

Murray, don't you think that your tikosyn medication is keeping you out of afib? Maybe you will have to stop the tikosyn in order to go back into afib, difficult as it may be to get back onto it. Best to you whatever you decide.

PeggyM

It is an ongoing debate in cardiology weather ablation should be considered the first line therapy for atrial fibrillation. My opinion is that there is no one answer and it really depends on the individual. First of all current ablation techniques (PVI) are highly effective only in patients who have minimal atrial fibrosis and normal left atrial diameter. Studies by Nassir F. Marrouche confirmed that if a person has less than 5% atrial fibrosis, as defined by MRI, standard PVI has almost 100% one-year success rate. Therefore, I think in patients like that ablation should definitely be considered first-line therapy. However, if a person has 5-20% atrial fibrosis the success of ablation drops to roughly 70% at one year. For a patient who has over 35% atrial fibrosis the success of ablation is less than 50%.

Therefore, when making a decision weather to undergo an ablation or what is the best time to do it, I think one must use individualized approach which relies on some quantifiable means to guide the decision making process. Getting a DE-MRI to assess the quantity of atrial fibrosis would be a good step. For a patient with minimal fibrosis, standard ablation would most likely do the trick and result in long lasting freedom from AF. However, an average AF patient has between 5-35% fibrosis, therefore the decision is not that straightforward. PVI will not work, because it can not possible modify the substrate that drives the arrhythmia. In that case, it might be wise to wait until rotor and focal beat ablation becomes the mainstream procedure.

My intention is to remain on TIKOSYN for as long as it is working for me and keeping me in NSR, etc. My LA continues to shrink; how much and how far is anyone's guess but they hope it will drop AT LEAST down below 50mm. and hopefully back to its 'normal' size.... in the 40 range. I can afford to wait as long as it is working, but regretably, it does not continue to work or cannot be tolerated indefinitely by most folks and that's the point where one starts to scratch their heads. If in 'the range' I would be thinking very seriously about ablation, even if the success rate was 50% for a single procedure. It is the path less travelled that I may be headed for and I would like to think that over the next few years progress in ablation technology will advance in leaps and bounds.

In the meantime, if I knew two years ago (or more) what I know today? If I knew that I'd be dealing with a succession of "quacks" before finding my "pro's".... I'd be having a top rated EP doing a top rated ablation in a top rated facility. No question in my mind. It was this two year wait that screwed me up. Nobody ever diagnosed or suggested the aFib word to me until my wife asked our GP to do an ECG right in his office one day. So I can add a couple of years to THAT two years most probably to give me about four years fighting aFib before getting to the right person to take care of me. And I can see, as clear as day, like a bucket of cold water poured over my head, just what the cost of misdiagnosis and mistreatment has cost me. What is the answer in Ontario? I don't know. I do know that every time I had an ECG it was NSR... but only a snapshot of one minute in a 24 hour day. A snapshot in time. It was not until I was already diagnosed, by accident, that I was even put on a Holter monitor. Go figure.

TIKOSYN appears to be working very well but is toxic indeed with variable side effects that shut me down on some days for half the day or more. After 9 months on TIKOSYN I do not seem to be able to induce even ten seconds of aFib no matter what I do. I am presently in NSR solid as a rock it would appear. And waiting for my LA to shrink to be eligible for a successful ablation, although the plan is probably to remain on TIKOSYN as long as it is working and my LA is shrinking. Then again, do I really want to wait until the meds no longer keep me in NSR? Or do I want to pick my time for ablation? So like I say, going back a few years, if I knew where I was headed I would have chosen ablation by one of the best and taken it from there. But that is just me. It is very very much a personal decision.

Murray L

--------------------------------------------------------------------------
Tikosyn uptake Dec 2011 500ug b.i.d. NSR since!
Herein lies opinion, not professional advice, which all are well advised to seek.

Thanks Namor, some interesting information.
Nancy

Here is a video from Stopafib.org concerning Focal Beat and Rotor Ablation-

[www.stopafib.org]

EB

Hi Namor,

Good post above with some excellent insights. One point to add though is that t,he option now isn't only limited to a strict 'go or no go' on ablation due strictly to fibrosis percentage as Marrouche's study seems to indicate. Yes the data conveys an important reality about AFIB progression. and it seems particularly compelling compared to standard PVI done in general centers ..But the options now are not only down to either you having very little fibrosis or else having to wait until more FIRM rotor/focal ablations are confirmed and made available.

Both Haissaguerre/Jais at Bordeaux and Natale and his groups have had significant success with persistent AFIB (which by definition almost guarantees the presence of at least a moderate to significant degree of scarring/fibrosis in the left atrium), as well as a good number of patients with larger atriums.. even though it is true that the larger the atrium the more difficult the chances for one procedure to give long term success and above a certain point the risk/benefit does drop off significantly even with top ablationist.

But the reason there is already hope and another option for many who would otherwise be deemed unsuitable for ablation by these criteria,is that these more experienced groups do not limit their work to 'standard PVI', and already do address focal triggers spots as well as common anatomical regions when confirmed by mapping to be active .. also CAFEs ( complex fractionated electrograms) ... and in the process ablate rotors as well already.

Hopefully, the Topera system does provide some new and improved mapping strategies to make it easier for less experienced operators to locate and address the most offending focal/rotor triggers in addition to their anatomical PVI ablations for overall greater success with a wider range of patients beyond the really easy cohort of people with very mild AFIB and hardly any fibrosis.

But I'm still more than a little skeptical that the FIRM system represents anything really revolutionary. Certainly compared to run of the mill anatomical PVI the FIRM system may well seem like a real 'breakthrough', but some of these early study reports on FIRM have seemed to bend over backward to give a biased advantage to their system in comparison by using only anatomical PVI as the control in spite of including a large percentage of persistent AFIB patients which is guaranteed to make the anatomical-only PVI results look very dismal indeed!

Yes, if it proves out in much larger and more independent multi-center trials, that will be helpful and perhaps the Topera computer will offer another valuable tool to help more EPs do a better job the first time around. But just how effective and how reliable their data is still remains to be seen.

Nevertheless, at this point, I would hate to be one of those that are/were condemned by Marrouche's new fibrosis flow-chart to 'not being a candidate for ablation' as I surely was prior to my 2008 Natale ablation for persistent AFIB!

And yet, I have not had one second of AFIB since that day over four years ago thanks to an EP not constrained by those ideas. The same can be said for many Haissaguerre/Jais patients as well, so there are other options, notwithstanding the very valid points about fibrosis and its increasing demands on the skill of the operator as the degree of fibrosis increases, and that Marrouche's valuable study certainly underscores!

That is also another good reason not to wait too long for an ablation,even with the best operators doing the work, if all other more conservative and natural measures haven't stopped the triggering.

Shannon

I look at the interview with Sanjiv Narayan at UCSD and sure, it gives me some pause, if I can get 15 mins of ablation versus an hour or two to fix the AF ! . But as I'm already scheduled, I'm reluctant to postpone it and wait for months or years for this technique to get into general use, if it holds up. The interview makes PVI seem kind of old-fashioned almost

Shannon, I would like to add Dr. Hocini in on the list of all stars. Although my so far successful 3rd ablation done in Bordeaux by Hocini is only 6 months old I feel strongly that it will be successful for some time to come. I perhaps waited too long to have and ablation because my paroxysmal afib had turned into persistent/permanent by the time of my first ablation. The first and second were done here in Edmonton by two different Dr.'s. I was on a waiting list for the third when I decided to pay the money to see the best. I don't feel short changed for not seeing Haisseguerre or Jais. Just Sayin.

Thanks for all your well crafted informative posts. They are a pleasure to read.

Adrian

Hi Murray,

Iv'e been thinking about you a lot lately. Don't worry, all my thoughts are good ones.
I have a fellow afibber friend who lives in Kelowna B.C. Like many of us, he has been battling afib for a long a time. There comes a time with most of us, when we choose the
ablation route.
My friend is off to Bordeaux in early November for an ablation. I really don't think it matters wether you have Pro. Haissaguerre, Pro. Jais or Dr. Hocini operate on you. They
are without doubt three of the best in the world.
Even if over time your left atrium remains enlarged, I would bet that If you sent all of your info to Bordeaux they would say lets set a date.
I was there in Sept. 2005 and at that time I was told they had an 80% success rate after the first ablation. and an even higher success rate if a touch up was required. In
hindsight I wish I would have stayed around a few more days for a touch up. As it turned out I got four wonderful years of being afib free.
Last April I had a touch up done in Vancouver. They re ablated my left pulmonary veins which had become active again. I have had six two hr. or less afib events so far. On
the bright side, my heart has been relatively calm for the last six weeks, with no afib. Fingers crossed.
If I don't get a successful outcome here I will definitely consider returning to Bordeaux. I have been in contact with them and even after seven years they will still give me a
reduced rate.
In 2005 it cost me $25,000 which includes every expense. At that time it cost $1.56 Canadian for one euro. Today a euro would cost $1.26, which makes it a lot more
affordable. You would also receive around $5,000 back at tax time.
There is a big light at the end of the tunnel for you, so don't ever give up hope.
If you ever need info on Bordeaux let me know. I am sending off some maps and an info package to my friend in Kelowna.

Best wishes from Langley B.C.

Lou

Yep Adrian, Dr Hocini is definitely in the top EP list with her long training under, and close work with, both Haissaguerre and Jais as a very important member of the Bordeaux team.

Thanks for the shout out for her!

Shannon

Thanks for that information Lou. Encouragement is always appreciated.... and shared by all who read it. I have an appointment with my EP in November after wearing an event monitor for two weeks that is set to autodetect aFib and has an EVENT button in the event of racing pulse or palpatations, etc., so they can see what is happening. In the study that I am trying to get into they do the same every 3 months I believe to keep a closer eye on how things are going and hopefully I will get off the TIKOSYN at some point and have an ablation by Dr. Khaykin or Verma at Southlake. I'd really like to see what NSR feels without these toxic drugs which are beginning to have side effects that are 'growing'. Morning nausea (not pregnant, sic), fuzzy head, etc.

Murray L

--------------------------------------------------------------------------
Tikosyn uptake Dec 2011 500ug b.i.d. NSR since!
Herein lies opinion, not professional advice, which all are well advised to seek.

Some more food for thought. Dr. Verma said to me on my first visit that at 60mm. I was playing with fire. The odds for a successful ablation were greatly reduced at that size; and the smaller the left atrium the greater the chance of successful ablation. There were other risk factors that increased significantly at that size and the ablation became much more difficult. The atrium wall became very thin as well. I am down to 56mm after 6 months in NSR mostly.... and the hope is that it will continue to shrink. Under 55mm. Drs. Verma and Khaykin will consider an ablation. In the 40's chances of success greatly increase and at normal (40ish) you have as good a chance as you will ever have.

Not sure where you are located Lou, but note shawcable.... so assume it is Canada, like me. In Ontario, the whole shebang is covered by OHIP. Get the ablation done outside of Ontario and unless you make a VERY compelling case you get not a plug nickle unless it was done as emergency surgery and even then, you get paid the Ontario rate and are stuck with the rest of the bill. Not that $25K is anything to sneeze at but I think we have two of the best just up the road here in the persons of Drs. Verma and Khaykin. A little confusion still reigns.

The TIKOSYN is a wonder drug, but considering that it only takes 100 - 200 MICROgrams to radically slow down things and normalize NSR, it is, as my doctor friends suggest, a very very toxic drug. I am on the max of 500 micrograms twice a day, of which 80% is filtered out and goes down the drain within TWO HOURS, leaving me with about 200 MICROgrams a day working on my system.

The side effects are not terrible now but are dibilitating for a few hours in the morning until my head clears and the nausea subsides. I can do nothing. If the effects increase I am going to have to stop taking the TIKOSYN or at least plan for ablation while taking it with a view to cessation of TIKOSYN therapy at the earliest opportunity. I have heard of folks who have had much much more dramatic side effects to the point of seeing pink elephants.... I don't want to go there.

So, we know we have some options and that is reassuring to be certain. I'd like to try and stay in Ontario and save that big bill for the trip to Bordeaux, although I'd like a vacation in France.

I'd like very much to get into this study group and will have to just wait until my appointment with Dr. Verma in 3 or 4 weeks in order to find out if the event monitor picked up any signs of aFib. I am thinking it picked up a load of PAC/PVC's, skipped beats, etc. The strange thing is that even when my heart was racing at 120 bpm (and that is with 25mg Metoprolol b.i.d.!) the rhythm seemed to be regular viewed on a pulse oximeter. On the other hand, I am pretty sure that what I am seeing on the pulse oximeter is VENTRICULAR and not ATRIAL action. I do see a 'ragged' pulse from time to time when racing and at other times, a perfect sine wave pulse indication. Skipped beats, PVC/PAC's are obvious as it simply flatlines for a moment.

The portable mini ECG is hard to read as it is only three leads; the Q wave is lost in the noise mostly, but I can read the peaks clearly and for the most part they are regular... am hoping that the event monitor has picked up otherwise as I cannot monitor using the ECG all the time obviously. It is worth having, but only if one is prone to longer strings of aFib that can be seen in time. Mine are disappearing withing seconds. Feels like trying to break through but not lasting more than a minute, unlike when I first started the TIKOSYN and they would last up to a half hour when I ate trigger foods in error. Even with trigger foods ingested today? NADA. Even MSG, caffeine, cold drinks, glucose overload, etc., etc. NADA. The most I am seeing or feeling is the odd run of palpatations for a bit (say 20 - 30 seconds generally).

Go figure. When you want aFib for 30 seconds it eludes you. When you don't want aFib but rather NSR, THAT eludes you. Sic.

Murray L

--------------------------------------------------------------------------
Tikosyn uptake Dec 2011 500ug b.i.d. NSR since!
Herein lies opinion, not professional advice, which all are well advised to seek.

Hi Murray,

I live in Langley B.C. which is about 50 kilometers east of Vancouver. I'm pretty sure Hans put out a list of Electrophysiologists available in Canada a while back, and I believe Dr. Khaykin was on it. I know it is next to impossible to get financial assistance from the government when travelling out of country for an ablation. I do know of one individual who went to Bordeaux, and received financial help. I want to have some options other than a return to Bordeaux. I've been retired for three years now and really don't want to disrupt my retirement income unless I absolutely have to. I haven't looked into the possibility of going to another province for an ablation. I am sure there would be a lot of red tape involved.
Keep us posted on the study group and how your atrium is doing.
Positive thoughts to you Murray,

Lou

Nancy - I don't know which Kaiser you belong to and whether they will refer you out to another region's specialty center. Kaiser in Santa Clara is probably the highest volume AF ablation center in California and they have an experienced crew there. There was a fellow here that posted on his (successful?) experience in Kaiser LA as well.

Regarding waiting for FIRM and Topera. The computation step takes about half and hour per mapping and it is not automatic. You need real time access to computer programmer and i assume a mathematician the last time I checked which was a few months ago. Not very scalable at this stage for routine usage and not sure when "prime time" will happen following the evaluation of the beta testing now happening. The computation is a huge stumbling block. I don't know what methods they are using to solve the PDEs (partial diff equations) but if I were them. I would look at other approaches and get the computational step down to 1 minute or less. There is another company working a a multi-electrode vest that worn on the outside of the body. I am pretty sure computation is the stumbling block there too.