Coumadin for Afib

[axg9504]

I have had exercise intolerance for about 2 1/2 years now. Recently event  monitor testing showed tachycardia 120-160 beats per min and some burst of atrial fib during running. I have light-headedness only when doing areobic exercise and only after reaching a certain threshold level. I did have a TIA 11 years ago, but had none of these problems at that time. I have 2 Q's. Are there people who have paroxysmal Afib that occur only during exercise and never otherwise ? Would you recommend I take Coumadin when I am possibly experiencing Afib no more than a few minutes a week (on the treadmill)? I am 60, male and have a structurally sound heart and normal BP. Thanks.

[Cleveland Clinic]

axg,

I cannot recommend medicines over this forum.  

What I can tell you is that even people with paroxysmal atrial fibrillation have an increased risk for stroke and embolic complications from thier fibrillation.  The fact youve had a TIA in the past, unless it is well documented that it was not associated with fibrillation is a very big risk factor for having a complication from fibrillation.  

Coumadin tends to be markedly underused because physicians and patients tend to underestimate the benefits and overestimate the risks associated with continuous oral anticoagulation.

I would discuss your case with someone who treats fibrillation regularly to make this decision.

good luck

[dquenzer]

Sounds just like me (age 49), except my AFIB occurred when I wasn't exercising as well.

I'm not a doctor,and it will be good to read the comment, but when I had an ablation the EP did a pulmonary vein ablation and also for atrial flutter (a fast heart rate).  The atrial flutter would occur during exercise and then it would turn into AFIB.  Strangely it only occured when I was running outside in cold weather.  If you have been a runner most of your life with a low heart rate, you might have developed paroxymal AFIB from the stretching of the pulmonary veins.  That was the theory of my EP at Mayo.  He says they see lots of AFIB among runners, hockey players and basketball players.

As to coumadin there are all sorts of theories.  One cardiologist I went to said I should take it, another said an adult aspirin if I'm not getting AFIB all the time.  I decided to go the aspirin route because at age 49 I was still too active.

I am now AFIB and atrial flutter free since ablation, but I still take one adult aspirin a day.  

I think you are going to find numerous opinions on coumadin.  I think it's going to be a personal call.  Most lean toward coumadin.

I encourage you to go to an EP at a large medical facility.  You might be a candidate for an ablation.

[Erik36]

Do you think they would do PVI for a 36 year old male who has only had one sustained episode of A-Fib three years ago? My episode only lasted four hours. I have had several short runs lasting 10-15 seconds at the most. I was on coumadin for a few weeks after my Four hour episode but then my doctor switched me to aspirin which I no longer take because of acid reflux.

Do you think they would even do an EP study considering how seldom I get A-Fib? Thanks.


Erik

[pms_barbie]

Eric I seriously doubt that a dr would even consider an ep study for something that happened 3 years ago.  Not unless it occurs again.  Because what ever triggered it 3 years ago may not be present any longer.  I know how scary these arrythmias are hun and I do not be little your concern over it.  However a one time incident doesnt warrant an ep study.  Take it from some one who has had them.    There not all that horrible a procedure however there are real risk that go along with it.  Mine was for bigeminy and i mean every day bigeminy that lasted for long periods of time.  The bigeminy for the most part is gone but the pvcs remain.  I doubt they will go back in and get the spots throwing off the pvcs and I have them daily....Hope things stay good and you stay out of afib.  Stephanie

[Erik36]

Thanks for the nice comment.

[hankstar]

Just my opinion your a-fib doesn't warrant such an invasive procedure and you seem to being doing well on the meds. I don't know if you drink alcohol, but some wine , beer or mixed drink could have triggered your episode of a-fib, also high stress at the time or it might have occurred for no reason that can be identified.

On another note you seemed to a bit obssessed with rising your good choloestrol levels(no offence intended pal) I guess we are almost in the same boat regarding obsessing!!!

Be contented and reassured, your risk for a coronary heart disease seems to be quite low. One of the biggest markers regardless of choloestrol , high B/P ,inflammatory markers are a strong family history, most cardiologist will tell you this.

Of course there is always an odd ball that has the perfect family history , does all the right things and  develop heart disease, then there is those that has a bad family hitory, does all the wrong things and never develop heart disease.

All we can do is live life to the fullest and deal with the hand we are dealt regardless of what it might be and never give up or give in to what ever befalls us until we have no absolute control over it anymore.

Take care.

[dquenzer]

Erik,

I don't think they would based upon my experience.

At Mayo their philosophy is that you must fail two meds keeping you in rythmn.  If I only had short runs of AFIB being on meds I would still be on meds.  I would do very well on meds for awhile and then after 4 to 6 months I would "break through" and start having episodes that would last for hours (2 to 18) almost weekly.

I think that if you are only having short runs once in awhile you shouldn't even worry about it.  If you are having other irregularities other than AFIB they might consider it depending upon how symptomatic you are.  I also had atrial flutter and large numbers of PAC's.  I haven't had atrial flutter since (at least to my knowledge), and I hardly have any PAC's anymore.

Your AFIB is definitely something to keep tabs on.  I suspect (although I sure hope you don't) that as you get older (I'm 49) you will be more susceptible to longer AFIB bouts.  So when you get to that point I would definitely have the EP study.  It's great to know that there is now hope for AFIB sufferers.

[Erik36]

Thank you very much for the good information. I appreciate your comments.


Erik

[axg9504]

First thanks to the doctors on this board and the posters who provide an invaluable service. Q for Dquenzer: at what point did you decide on the ablation? Did you have frequent and prolonged bouts of Afib. Also do any of you Afib sufferers experience a clutching sensation at the throat? Before I get into the light headedness phase on the treadmill I have this sensation which is uncomfortable which starts after I've run a mile.
I am seeing an EP and he had recommended Coumadin. I am hesitating because I had tried Toprol and Rythmol for a week each and quit because they aggravated my symptoms. I am going to try Inderal next to see if it can help me run (more than a mile).
SO I hesitate to take something that will inhbit my lifestyle if the risks of not doing so are small.
Finally my EP tells me that my wrist BP monitor that shows very slow heart rates (50-60) when I have my dizziness (and for about 15 mts afterward) can't be trusted and that my true rates are probably higher. How do I tell if I'm in Afib if I am not having dizziness? My pulse seems to be steady when I take it. Thanks again to all.

[Shiloh Girl]

I am a 54 yr. old female -had afib with rapid ventricular response since 1999.  I have been on 900 mg. of Rythmol daily for the past 4 years.  Since August I have been having weekly episodes 4 to 8 hrs. in length.  My ekg's are always abnormal or borderline with abnormal T waves or R waves or P waves.  Stress test had ST depression at peak exercise with trival leakage around aortic and mitral valves.  I was sent to electrophys. who said I was a candidate for AV node ablation with pacemaker.

I do not know if I am ready for that procedure yet.  I am a school principal and this year has been very stressful.  However, I plan to retire at the end of this year so I am thinking, why zap the node and become dependent on pacemaker if stress relief of retirment will help the problem.

I am an active person and plan to become more active on retirement.  Also - I am not on coumadin, just asprin but if I get the pacemaker I will have to be on coumadin.  Is the risk of stroke just as great on the pacemaker as it is off.

Anyone in a similar situation?

[axg9504]

I think the pacemaker implant is done when the ablation results in too low a heart beat. The stroke risk from Afib is due to the possibility that blood may pool in the atrium because of the inadequate pumping action of the ventricles during an Afib episode and that this blood may then clot and make its way to the brain.
When you experience Afib, what physical symptoms do you have? Have you ever checked your heart rate with a BP monitor during Afib to see what readings you get?

[Shiloh Girl]

Many times - anywhere from 102 to 120 - very tired afterward, increased urination, some time shortness of breath.  I know the pacemaker would be the heart beat due to the fact that the atria is no longer communicating to the ventricles.

[axg9504]

Interesting - your heart rate I mean. I had been carrying my wrist BP monitor with me to the treadmill and I have seen low readings (50-60 I'm usually around 80-90 at rest) when I had my light headedness. My doc said that you can't trust a BP monitor when you are having Afib. Also I never have shortness of breath, I do get tired and light headed, but I recover in about half an hour. Good luck!

[JCB]

I don't know if either of you have used a heart rate monitor to observe you heart rates, but my heart rate monitor accurately measures my heart rate and has detected the onset and presence of A-F. I have used wrist and desktop BP monitors and the wrist monitor is more bulky than my heart rate monitor.

I started using a heart rate monitor to track conditioning during exercising and observed that it detected occasional short runs of A-F. I upgraded to a model where my heart rate is recorded every five seconds for up to 5.5 hours (my exercise routines - tennis, running, etc. - are completed before this time runs out. I download the traces to my computer for later review and comparison.

I think the doctors don't trust the pulse rates when you are in A-F because the rates are quite variable. Mine would start as high as 200+ and gradually decrease to less than 100 bpm, but the peaks between beats would be high (+/- 20 bpm or higher) where normally the peaks would be =/- 4 bpm. One the A-F converts, the variation returns to normal.

Again, if you haven't considered this, a HR monitor may be of use.

Good Luck!

[axg9504]

I only have an Omron wrist BP monitor. Could you suggest a brand of HR monitor, perhaps the one you use. I looked at ones made by Polar but I seem to recollect that they said readings would not be reliable in the presence of Afib.

[JCB]

My heart rate monitor is a Polar Accurex Plus. This is a 1997 model with storage and downloading capability. They now have newer models with easier downloading capability (USB interfaces or wireless connections to the computer software).

I agree that the readings are not reliable because they change frequently (the signals have a lot of noise). However, the noisy signals are real, i.e. that's what your heart rate is doing. When I had the occasional run of A-F, the monitor detected it. I think most of us who have experienced this unpleasantness know when it is occurring, because I wear my monitor whenever I exercise, I have been able to capture these events and document them with recorded data. Having viewed the recorded tracings, I also know what the variations look like when I read pulse rate by looking at the display.

Again, I originally purchased my heart rate monitors to enhance my exercise routines. I have observed the effect of cardizem and other medicines (eg. demerol) on lowering of my maximum heart rate during exercise.

This may be more than you wanted to know, but Polar (I have 2) has worked for me.

[axg9504]

Thanks for the info, I have been looking at the Timex models too.One last Q. I see you are running with Afib. Do you not have problems with dizziness. I can't run (and walk) more than 1 1/2 miles. After that I get dizzy if I tried to run at a sustained pace. What symptoms do you have? Are you on a blocker? Thanks

[JCB]

I have experienced "lone afib". It occurs infrequently, and when it does, it usually converts on its own fairly quickly. My favorite sport is tennis and I have experienced an occasional (once or twice per year) bout of Afib on the courts but the conversion is quick and I haven't had to stop a match yet (40+ years of play).

However, I have had a few runs of Afib induced by cold drinks and it hasn't converted (even with vagal movements) resulting in a few visits (2 times in 4 years) to the emergency room.

Hence, I am not in Afib frequently. I have cardizem to slow the heart rate if an event occurs with the expectation that it will convert, and to date this works. I have experienced light headiness (even blurred vision) only once. This was several years ago and I had my monitor on, and my rate was irregular and near 180 bpm. This was one of the times when I went to the emergency room. I was also overweight and not exercising regularly. One of the significant changes that I observed using my heart rate monitor was that the rate of recovery (time from maximum rate to near resting rate) improved as my conditioning improved. The maximum rate at the same intensity of exercise also decreased.

Although my experience is with Polar, I expect that most of them will perform similarly.

[axg9504]

I hope I'm not misusing the board by posting too much but I never seem to get all my q's out at once. Your case is interesting to me so if you don't mind... 1. Are you taking Coumadin or Aspirin regularly? 2. What is the natural variation that one can expect in bpm. while exercising? I have no symptoms other than light headedness which occurs at an exactly predictable interval after I get on the treadmill during my fixed exercise routine. Now I can go slower and avoid it altogether. My wrist BP monitor has told me on many occasions that towards the end of my routine, my bpm is on the low side 50-60. Since I've never used an HRM and don't have any symptoms other than the light headedness (and a clutching sensation in the throat), what variation in readings would I use as a guide to tell me I might be in Afib? BTW, I was an avid tennis player too. Thanks for all your comments. Also I am thinking of buying the Timex 5C351 - it costs around $50. A data recorder is also available for about the same price.

[dquenzer]

I just read your question to me concerning the question of how I came to get an ablation.

I decided to get an ablation for four basic reasons:
1)  Medications were not working.  They would work for awhile and then fail.  I was having a bout it seems every week or two for hours at a time.
2)  AFIB made me tired.  I could function, but I felt energy drain while in AFIB.  I wasn't willing to live with that. Had I not felt the energy drain I may have decided differently
3)  The EP from May looked at my history and felt very strongly that my problem was due to being a runner (particulary a track runner in high school and college).  They see lots of AFIB in highly conditioned athletes due to what they call pulmonary vein stretching.  Therefore they felt success would be very high.
4)  I did not want to be on anti-coagulants.  I wanted to live a fairly active life and coumadin if not regulated very well can be hazardous.

Much of this had to do with the aggressive nature of my cardiologist who felt that AFIB should not be tolerated and that staying in rythmn is a necessity rather than a luxury.  I think there are some who feel differently.

Hope that helps.  I would really encourage you to consider an ablation if your EP feels strongly it would help.  I have felt so good since.  I continue to run and remain active.

[axg9504]

Thanks. I am actually seeing differences of opinion between my regular (interventional) cardio. and the EP. The former is the one that seems to be more interested in finding the source of Afib. My EP indicated that at this time he would not recommend further study. He seems to feel that ablation (especially PV ablation - he is positive the irritable focus is the PV) has not yet reached a mature stage, or rather there will be better techniques available in a few years. My Afib as far as has been documented occurs only for a minute or two during exercise. I am also constrained, where I live, and by my HMO insurance plan as to who I can see.

[dquenzer]

If your AFIB only occurs briefly then I doubt they will be able to get a good ablation.  They really need to see where the foci occur.

My AFIB would occur for hours not a few minutes.  Therefore they were able to get a very good read on where it was originating and where to ablate.

I think medication is a more appropriate form of treatment if you are in AFIB for only a minute or so.

[JCB]

1. Are you taking Coumadin or Aspirin regularly?

   I have taken an 325 mg aspirin tablet everyday for 4 years. I
   also take a multivitamin and magnesium tablet. My cardio
   offered coumadin, but I declined (he wasn't emphatic about
   this).

2. What is the natural variation that one can expect in bpm.
    while exercising?

    My (emphasis on My) nominal variation is +/- 2 to 4 bpm at
    rest (eg. 60 avg, 58 to 62)or at peak (eg. 160 avg, 158 to
    162) exercise. The variation during a run of A-F can be as
    high as +/- 20 bpm (eg. 80 avg, 60 to 100 bpm).

Your nominal rates appear to be much lower than mine. When I have gotten a run of A-F, my rate goes high. When the rate returns to a low value (usually less than 60), it usually converts to normal ryhthm.

If you are familiar with the tennis rating system, I play at 4.0 to 4.5 levels, so some of the matches are quite intense. I also play in South Carolina and Miami summers. Maximum rates while exercising in intense heat is another story.

[axg9504]

Thanks for the input. I ordered a Timex with a data recorder. I am now however having PVC/PAC's. I have had them consistently only once (a month ago) for a couple of weeks. It went away when I took Rythmol to prevent Afib(which it did not and I quit). Anyway, when I went back to my interventional cardio yesterday, he agreed with me that Asprin would be OK since I have Afib only when I exercise and then only for a few minutes (although I am not sure whether I am in it now with these missed heartbeats creating a mild thud every now and then). I mentioned the HRM and he said that it won't show Afib because Afib is a rhythm and he is right. Afib is diagnosed not only through heart rate variations but an absent p-wave and other patterns on the ECG. He is going to put me on an event recorder for a month so that we can try to document whether I have Afib at rest and after moderate exercise. Still the HRM will help correlate the results of the event monitor. You are a better tennis player than I (was). I probably played at the 3.0-3.5 level mainly because I could not vary my serve and was very inconsistent. I live in SC.

[JCB]

My Cardiologist said the same thing to me several years ago when I told him about my HRM and my A-F (i.e. he needs to see rythym). However, I can "feel" the rythym while the HRM displays the (highly variable) rate. I have been told by several people that they are in A-F constantly and I don't understand this since I have never experienced it. Based on my 30+ years with this condition (some years I have had zero episodes), I would be concerned if I were in A-F constantly. My cardio attempted to put me on Meds several ago, and each one we tried caused worse arrythmias than I had experienced. I also met with an EP and concluded that I was not interested in ablations.

I have 5 years of data (4 to 5 episodes a year) and a 100% correlation between my experiencing A-F and the rates recorded by my HRM. I also have confirming data when I have gone to the emergency room (4 times) and the EKG has indicated A-F as read by the doctor after I "told" them that I was in A-F when admitted.

I have never been diagnosed with PAC's or PVC's so I don't know how these would present on a HRM. I do know what my baseline HR looks like and that it also correlates with "official" indications that my A-F has converted. My confidence in the readings from my HRM may be due to the fact that I don't have any other complicating rythyms.

I expect that your HRM will be very revealing to you.

Take care and good luck.

[axg9504]

Your situation is very much like mine, as I probably have stated before. Meds make me worse as two Beta Blockers have already shown. Got my HRM this weekend and went out on a run with it on. My resting bpm is around 72 with +- 2 bpm as you indicated. My bpm went up quickly to 120 and then to 140 during the run fluctuating about 10 bpm and then after 7/10 mile, very predictably it plummeted to 60, and I had to stop running because resumption resulted in dizziness. In the past event monitor readings taken when I had dizziness has indicated "bursts" of atrial fib (as the EP documented it). However the EP's event monitor has no indication of low bpm. When I have a dizziness episode, the HRM tells me that my bpm stays in the 50-60 range for 5-10 mts and then kicks abruptly up to the 80's and then works its way back to normal. I will be getting an event monitor this week from my cardio to shed more light on this. Except for the light headedness after the run, which goes away in about 10 mts I am fine and have never felt like I needed help. Thanks again for your input.

[dquenzer]

Are you getting AFIB every time you run or most of the time?

Personally I wouldn't tolerate AFIB every time I exercised.  Also if you are getting lots of PAC's they are most likely triggers for your AFIB.  

I think whenever AFIB cannot be controlled by meds (which it seems like you are sensitive to) and it is taking something out of your life that would affect your enjoyment of life (exercise), then you should go to an EP and consider an ablation.

I agree with your cardio about taking a more aggressive approach to that.  In my earlier post I thought these episodes were rare, but they sound like they are exercise induced and occur most of the time.  Is that correct?

[JCB]

Your symptoms are quite different from mine. When I have had a run of Afib, my rate goes high (greater than 240 bpm), then the rapid, irregular heartbeats start. My rate remains high and irregular gradually returning to normal either within minutes or over several hours (20 hours max with visit to ER). Like you, when my rate returns to normal, I feel fine and ready to continue with whatever activity in which I was involved. However, my events are rare and I do not experience dizziness except for the time mentioned in an earlier note. I have been playing tennis on a few occasions when I have experienced a high rate. I slowed down long enough to swallow hard and convert the rhythm back to normal and continued playing.

The variation in my normal rate as measured by my HRM is also the same at low and high rates when I am exercising (+/- 2). I normally walk and run outside where my rates are noticeably noisy. However, when I exercise on a treadmill, my rates increase in nice plateaus when the intensity is increased. These may be academic observations for you with your recent experience.

Our feelings of dizziness during these events may be the result of the same effect (i.e. inefficient pumping by the heart) but the root cause appears to be different (high rate vs low rate).

I agree with dquenzer's comments and I hope you find the root cause and get well soon.

[axg9504]

Back in August I had 4 event monitor readings taken on the treadmill and sent to my EP. He came back with interpretations for 3 out of which 2 showed "bursts of Afib". All had tach.(according to the EP) of 130-160 bpm (however I was running at the limit of my current meager capacity). That's all I know at this point that has been documented. I'm going to get another event monitor this weekend to monitor runs where I don't progress to dizziness to see whether I can correlate the Afib to my physical symptoms. Yes for 2 1/2 years I have had this very predictable exercise pattern that leads to dizziness. If I run at a certain pace and walk when I get tired, after a certain point I cannot run at the same pace that I started, without getting light headed. I go home light headed and about 15 mts later I am fine. Dquenzer may be right about PAC/PVC's. When this problem first started I notice that the precursor to the dizzy stage was a clutching sensation in the throat which I now recognize as the ectopic beats. I am now having some of these even at rest but they are not bad at all and don't last very long. I will be going to a new EP next year (changed my insurance from the limiting HMO I have this year) so I can pursue ablation if that is recommended. However I am also a person that is averse to taking medicines (turned down the Coumadin recommendation of my EP).Does having an ablation mean sacrificing anything? Does it lead to a pacemaker? I wouldn't want that.

[axg9504]

I think Afib can have different effects on the ventricular rate. It can either go up or go down (as in my case). However I have not seen very high (160+) yet before I go the low rates. My bpm picks up quickly at the first sign of exercise. Walking at 4 miles per hour brings it to about 120. Running at 7mt pace for about 1/10 to 2/10 mile will bring it up to 140+.

[dquenzer]

There are definitely associated risks with an ablation, but under skilled hands they are minimized.  

You will hear many of the horror stories when it comes to ablations because those will be posted most often.  It's kind of like the news.  Bad news is heard more than good.   The greatest risk of an ablation is not that you will have a pacemaker, but more likely that of bleeding at the entry points.

When you get your insurance changed my suggestion is that you look at large medical facilities that have a long history of doing ablations.  Now is not the time to let a rookie be your primary EP.

I happened to go to Mayo.  I think I had one of the best EP's in the country.  He was incredibly skilled.

By the way you will need to take coumadin for about 3 months after an ablation.

[axg9504]

I believe I did read your note on your ablation at Mayo in another thread. I live in the Charlotte NC area. We have some good EP's here. I can even go to Cleveland when my insurance switches over next year. However I don't think I'm a candidate for ablation yet with my intermittent exercise induced afib.

[va_tony]

Concerning your question as to when it's advisable to take coumadin:

Recently, researchers from the Washington University of Medicine in St. Louis have devised a simple model to help doctors and patients decide whether anticoagulation therapy is warranted for people who have afib. The model - called the CHADS model - assigns a score from 0 to 6, based on the patient's age and other medical conditions. You get 2 points if you've had a prior stroke, 1 point if you have congestive heart failure, 1 point for high blood pressure, 1 point for diabetes, and one point if you are age 75 or older.

Those with scores of 0 don't require coumadin, an aspirin a day will do. Those with 2 or more points should definitely be on coumadin. One point is iffy. I have one point (high BP) but my cardiologist was concerned because I have also mitral valve regurgitation and an enlarged atria, so wants me to take it. You can read more about this at the following URL: http://heartdisease.about.com/library/weekly/aa080601a.htm . They discuss the odds of getting a stroke when you have afib and depending on your score and treatment(w/aspirin, w/coumadin, etc.). For example, with a score of two and taking nothing, you have a 4% chance of getting a stroke in one year's time (this translates to about a 50/50 chance over ten years - - scary huh?). The coumadin reduces that to about a third of those values (50-50 over 30 years). It's up to you to decide if you want to take the chance.

BTW.  The duration and frequency of the afib doesn't effect your score.  Basically, once you start having PAF, you're considered to have the same long term risk as someone who is in continuous afib.

Best wishes,

Tony

[axg9504]

Actually, if one can assume that the risk of a stroke is 0.4 in each year (assumes that each year is independent of the other), the probability of a stroke in 10 years is 0.277 or 28% and in 20 years it is 37%.

[va_tony]

Aha! So you insist on a PRECISE calculation of the probability? LOL!

Sorry to say but I think you are wrong as well!

Your 10 year 0.277 number indicates that you are assuming a binomial distribution with an event probability of p=0.04, N=10 trials,  and an exact oucome of K=1 stroke.  Sites like http://www.ciphersbyritter.com/JAVASCRP/BINOMPOI.HTM#Poisson provide a calculator for plugging in numbers like that. But I don't really need it. Where you err is that you are ASSUMING ONE and ONLY ONE stroke during that time.  You can theoretically have up to 10 successes (strokes) in 10 trials.  The proper way to calculate having AT LEAST one stroke is to first calculate the probability of having NO strokes (i.e., 0.96 to the 10th power or 0.6648) and subtract that probability from one.  The correct 10 year number is actually 0.335.  The 20 and 30 year numbers are 0.55 and 0.706.

As you can see, as a physics major, I took probability and statistics in college too. LOL.

Best wishes,

Tony

[axg9504]

Yes you are right I was assuming independent trials and using the Binomial distribution and calculating the prob. of one success (or failure!!. )I didn't consider more than one, because I hope I would learn a lesson before then and do something! I still wonder how they actually assign that probability though. The trials can't be independent, if I am sitting on a powder keg, the odds get worse each year. I am no biostatistican although I have had some stat long ago (I'm embarassed to talk about my academic background because I have never used any of it). They had 1700+ patients in that study, and there are some 4 factors involved. Did all of them have a stroke in the study? and so on. Good to hear from you! Thanks