Why anti-platelet and not anticoagulant

Hello all

Just thought I should let you all know why sometime people with AF are not put on anticoagulant (warfarin) And put on anti-platelet (Asprin).

This is because if you are not at high risk of getting a blood clot in your leg then you will be put on an anti-platelet , but if you are at high risk of getting a blood clot in you leg then you will be put straight on to anticoagulant. As the both work in different ways. An anti-platelet stops the blood sticking so it will not form a clot and will be good for blood circulation. An anticoagulant thins your blood so this stops the clot altogether thats why you have to be monitored all the time as the blood can become thin and you could end up bleeding internally. So remember as we are not all the same and many of you know this on this forum. If we are at lower risk of having a clot then anti platelet is ok but if we are at a higher risk of getting a clot then yes anticoagulant it is. Both my cardiologist and pharmacist oh and doctor told me this as I was worried as to why Asprin and not warfarin. I do hope this has helped a lot of you and that it has not confused you to much. I was glad the some people took the time to explain these to me as I had google these anti-platelet's and anticoagulant's.. Plus I do have family members who are doctors and pharmacist who also found out for me.. I do hope it's helped all of you who were not sure which one is which and why one and not the other..

36 Replies

  • hello mate . well i thought if you needed and anticoag then you take an anticoag . asprin is not an anticoag .and dont work as such . and i was lead to believe everyone with a f needs an anticoagulant . and not a headache tablet . ........unless someone tells me diffrent???? ..........moggy

  • Sorry but it is not that easy. Aspirin is an antiplatelet yes and has some uses in cardiac care for those with artificial valves and such and those with restricted blood flow into the heart muscles as it allows the blood to flow more easily but to say that it stops clots is not true. Warfarin and other NOACs are anticoagulants. They do NOT thin the blood in anyway. The viscosity stays exactly the same. What they do is reduce the thrombin content of the blood which is what creates clotting and by reducing the chance of thrombii (thrombusses? ) forming protects against strokes. Since the heart during AF is not pumping properly blood can pool and clots could form in the left atria or left atrial appendage and since they are in the heart they can become much larger than say one forming in a leg vein. Should they escape from the heart they will do far more damage and should they get to the brain the resulting stroke will be much worse. 80% of the worst strokes are AF induced. This is why it is so important to assess the risk using the CHADS2 or CHADS2VASC2 system and prescribe anticoagulants rather than aspirin which is about as useful as a chocolate firegaurd in preventing strokes in AF for those at risk. Sadly many GPs and quite a few cardiologists still refuse to see this despite ample documentary proof and continue to give aspirin which is just as bad for stomach bleeds as warfarin. yet does little to protect. Britain has the second lowest number of at risk patients actually on anticoagulation in Europe and we could save 8000 strokes a year if we could change this backward thinking and save millions on NHS budgets. Suggested reading--- see fact sheets on AFA main website.


  • I asked my INR nurse about the CHADS2VASC2 scores today and pointed out that it appears to clobber all ladies over 65 and she explained that it is a means of risk assessment of the likelihood of stroke - but for people who already have AF.

    I have a score of 3 and am on warfarin.

    I do think that 'having AF' is a bit vague. It obviously affects everyone very differently. I have arrhythmia occasionally, and much more than I used to and it's probably AF but I don't think it compromises my circulation very much. It starts off a bit wild and soon settles. I go weeks or months without a problem. I function reasonably well when it's there, but don't walk up stairs two at a time. I often find I am back in NSR and have no idea when it returned. I've twice had my heart totally at sea for a few minutes and found it scary. When I described the sensation to a doctor he told me that I was describing AF, but it was far worse than my usual dodgy heartbeat. And surely, when I'm in NSR (like 99% of the time) I don't have much more risk than anyone else.

  • Rellim, I think it is obvious that if we are on this site we have or have had AF and thus the system applies to all of us.! Now I used to think that not having it any more removed the stroke risk.. (At this point we must agree that we all of us have a stroke risk but yes AF people have a five times increased risk over those who have never had AF. ) About three years ago I met a specialist who changed that view for me by explaining that AF causes changes to the inside of the atria which makes the possibility of eddy currents more likely so even if like me you have had a successful ablation or three that risk continues yes even in NSR.

    As for what "having AF "means this is one of the big problems as it is such a mongrel condition that so few people experience it in the same way.. There are people like Ian who have permanent AF who have little if anything in the way of symptoms yet obviously are at risk. Then there will the the person who has paroxysmal AF once or twice a month who is prostrated by the thing during events. Neither is at any greater risk than the other but both are at risk.

    Ian has already used my line about drooling in a corner but for me that is a far greater fear than taking warfarin. any day.


  • Thanks, Bob, many, many thanks for this well reasoned, illuminating and most welcome reply.

    I think you've told me more in this answer than anyone else has in the last few months - and four of the GPs at the practice put their word in.

    I wish I had joined this forum earlier and understood as clearly as I do now. I had so much difficulty coming to terms with having to start taking warfarin and still don't get on with it very well.

    I'm really grateful Bob.

  • PS

    I feel you have set me on my path ahead, Bob.

  • Thanks Rellim, that is really gratifying to read. I have no medical training but have been lucky enough to be invited to sit on some committees and in meetings with some of the top people in the field over the last few years both EPs and anticoagulation specialists and have found that there is still a great reluctance in primary care to give anticoagulants despite the most recent evidence.. If your difficulty with warfarin is about staying in range then I feel sure that given time you will get used to it and it will settle down. If you have severe medical reaction to it then there are alternatives in the form of the Novel Oral Anti-Coagulants (NOACs) such as dabagatran and rivaroxaban but many primary care centres are reluctant to prescribe these due to cost.


  • Thanks, Bob. I do have trouble staying in range - have just dropped from 3.4 to 2.2 in a week, just when I was beginning to have some confidence and am now worried I will drop below 2 yet again. I have to wait two weeks before the next check. But next week will be the first Thursday this year that I have not had a surgery appointment.

  • Consistent ( but not necessarily boring)diet is important. Eat what you want so long as you do it all the time and don't have sudden binges.


  • Bob, my attention to diet has been a bit over the top, and food has beenvery dull, but what I think most influences my INR is exercise. 7 miles on the treadmill and down it goes.

  • Hi. I think you are right about exercise. I am quite active. I walk about 25 miles a week with my dogs and am on a high dose of warfarin.when I go on hols and am much less active my I.N.R. goes right up. I suppose you could say it's different food but as much as poss I do try to keep that consistent. X

  • Thanks Dedeottie, I was very careful last month when I had to have an INR over 2 in order to have an ablation. It was 2.7 the Thursday before and by Monday had shot up to 3.5 - had not eaten carelessly but had not had time for the treadmill. I think you take slightly more warfarin than I do - I'm currently at 8.3. When I walked 35 miles a week (5 a day) I kept on going down to 1.8 and was on 8.9mg warfarin.

  • Bob, would you say then that a person who is in permanent AF, rate controlled,is at a greater risk of stroke due to the cumulative effect of changes to the inside of the Atria with ongoing AF ?

  • Not as far as I know. The risk is a risk is a risk and is non accumulative.. Over a long period some people may experience enlargement of the atria which is not too good a thing but that depends on how well controlled the AF is by drugs. The bottom line is that most EPs agree that early intervention by ablation is the best way forward but sadly we need several hundred more EPs NOW and sheds loads more dosh in NHS budgets and that isn't going to happen any time in my lifetime I'm sure.


  • Bob, I was thinking more of the possible ' furring up ' of the inside of the atria . Wouldn't this be increased the longer one is in AF ?


  • From what I understand it doesn't fur up as you put it. The inside surface may develop a different texture which can cause the blood to eddy . This is finite as far as I understand and non accumulative.


  • Bob, thanks for explaining the difference so well.This should be circulated to all GP s. Sandra

  • Hi Sweetsugar

    I'm going to agree with Bob here and if you attend some of the AF conferences you will hear that some of the most common myths held by the medical profession are around asprin and warfarin and bleed risks. There is still debate around this I agree, but the evidence is now coming heavily down in favour of anti-coagulants.

    Your description of the difference in the ways that aspirin and anti-coagulants work is not correct, there is no thinning as Bob says, one works on the Thrombin and the other the Platelet, anti-platelets will not fully prevent the stroke risk of AF and that stroke risk is the very worst kind, as AF strokes are the worst forms of strokes.

    In terms of "internal bleed" the research shows some comforting and some not so comforting facts depending on who you read. In general warfarin out-performs aspirin in preventing stroke, that seems a solid fact, however the risk of "major" internal bleeed is higher with warfarin, but note the "major", it would seem that the risk of bleed is generally higher with aspirin, but that these bleeds are usual the less severe but potentially more longer term problematic gastro intestinal ones.

    I completely agree we are not all the same, and if your CHADS2VACS score is less than 2 it's your choice currently, however mine is 0 and I still want to be anti-coagulated, as has often been said, you can stop taking drugs, but you cannot undo a stroke, and they thought of ending up drooling in the corner is enough to ensure I take warfarin

    I highly recommend this site for you


    Finally the choice is of course yours, as it is with every patient with AF, but I doubt you will find a single EP (and they are the AF specialists after all) who would support the view that aspirin is sufficient.

    Be well


  • Hi Sweetsugar I agree with Bob and Ian because I was also at the AFA patient day where the leading expert in the UK gave us a very in depth lecture on blood coagulation and very firmly said that the term 'blood thinners' should not be used as the blood viscocity is not affected by either aspirin nor warfarin.

    As Bob says it isn't the leg DVT we AFibbers should be concerned with as much as the clots that form in the heart. I am appalled that you have been so misinformed.

  • Despite being considered low risk of stroke by my GP, this did not stop me having one and him regretting not putting me on anti coag sooner. Hindsight is a wonderful thing but preparation and precaution are even better when it comes to a/f and stroke risk. I wonder how long it will take before all medical professionals will take this on board? Anne

  • Hi Sweetsugar,

    Another one that definitely agrees with Bob and Ian. I've had TIA's prior to being on warfarin, when I had been prescribed aspirin, which as Bob says was as useless as a chocolate fireguard. I now look on warfarin as my friend since I don't want another TIA. The aspirin also caused a lot of stomach problems and the last time I took it caused me severe breathing dificulties.


  • Hi Sweetsugar

    My cousin had a series of TIAs at my age so although my risk score is 1 I opted for anti-coagulation (warfarin). I was on aspirin for a short while, but my GP actually agreed with me when I waved a newspaper article at him that said it wasn't useful in preventing AF-related strokes. It may help with other types, like leg DVT, I don't know, but I would back Bob and Ian here and say anticoagulants are the thing for AF.


  • Definitely agree with Bob. I had very low risk of stroke they said apart from being female so aspirin it was. Then...3 T.I.A.s and guess what? Yep warfarin.I wish they had prescribed warfarin straight away as the T.I.A.s left me feeling very anxious. I love warfarin as it is my ticket to a full life. Even when I'm having a bad A.F. attack at least I know a stroke is unlikely. I eat most things but have given up booze although there is no need to just because you are on warfarin. Moderation is the key. Hope this is helpful.x

  • Just to say the newNICE guidelines for AF do not recommend aspirin for af. If any one is having problems with gp's / specialists refer them to these.


  • I think it's scary that there are doctors out there who are still not clued up on this. People on here get to now more about their illness than their GPs!

  • Thank you all for this input and you have all frightened the living day lights out of me and even I am so confused why I am on a anti-platelet and not an anticoagulant. I don't know anymore I will ask my doctor when I see her next week. Although like I said I was told I have proximal AF last September and have been on bisoprlol and clopidegrel and been fine may be I am different. But after the post I put up I am frightened and very confused.. But thank you all very much all of you for such an amazing in put on this matter. I was already worried about booking a holiday to Florida in November this year as I had to cancel the one last year due to been diagnoses with PAF. But now after all these comment I am even more frightened of booking a holiday although my consultant did say it is ok as long as I have travel insurance which I do now. I don't think I can get on a flight now so scared and frightened......... I wonder if I will ever be able to get on a flight now.

  • You will! It doesn't hurt to be a little bit scared to start with as it puts you in fighting spirit to get what you need. Once you have ensured your safety all will be fine. It's good that we all look after each other on this forum.x

  • Hi Sweetsugar

    We don't want you frightened, that's not going to help anything, and may I say that the additional information that you are on clopidegerel does amend things a little.

    Yes it's still an anti-platelet, but it's usually only prescribed for two reasons, a) if you are allergic to aspirin, which I think you would have said and b) if they think you have other cardio vascular challenges other than just AF. And maybe that is the case, I am not sure. Anti-platelets do have a valid place alongside anti-coagulation when you have other cardio challenges I take both for example, but the aspirin does not prevent strokes the warfarin does.

    Can I suggest that before you do anything, take an online CHADS2VACS2 test just google it and you will find it easily, that's the stroke risk indicator for those of us with AF, and usually 2 or above you must be on anti-coagulant, 1 is the hard choice, and for doctors 0 usually means they do not prescribe, although increasingly EPs (the specialists) are saying you should be on anti-coags whatever your score.

    You will have read here stories from lots of people who literally have had strokes because their doctors prescribed aspirin, what you will not have read is stories of major bleeds, in fact in the 2 years ish I have been on this forum with now 1309 members I can only remember 2 stories of them. People who have had strokes? maybe 20 or 30, and that for me tells the story.

    You got some great advice about ringing the AFA, they will be able to talk you through your particular issues and give you advice, and they are very very helpful 01789 451837 ring them Monday morning.

    Re travel, there is no reason whatsoever not to travel, being on an anti-coagulant is not notifiable to the insurance company, so go for it and enjoy your holiday we all need a break and to get away from all the challenges and relax, you'll feel a lot better for it.

    Lastly you talk about your consultant, strong advice is that you need an EP and not a Cardio, as Bob so aptly says, why would you ask a plumber to fix your electrics? Think about that and discuss with your GP.

    Be well, and we are here for you between 1309 of us we have probably been there, done it and got the scars and the T Shirts so take advantage of us and ask away


  • Just a point Ian, every travel insurance company I applied to asks whether or not I am on an anti-coagulant which requires a blood test. As I am on one the NAO's I can truthfully answer no, but I have friends were it has caused a difficulty with some companies. I would suggest getting a quote with the ones that specialise in declared chronic conditions such as AF, they seem much more clued up and do not bump up the charges as much when you answer yes to the above question.

  • One more comment: people with general arteriosclerosis having coronary heart problems or stroke benefit from antiplatelet therapy (aspirin or other types of med) BUT the treatment for af generated stroke is anticoagulation as Bob and others have said. Some of us may, however, have both conditions and maybe need both treatments if severe problems

  • Sweetsugar, if you are classified as low risk, 0 or 1, your risk of af related stroke is considered so low that your dr didn't recommend warfarin. Although you have clopidogrel (antniplatelet drug) so maybe you have some other condition, which needs to be treated with that. Be calm and discuss with your dr once more.

  • Hi Sweetsugar before you go see your Dr I would suggest that you ring the AFA and have a chat with them, they are so helpful in this sort of situation. They have also produced loads of leaflets which you can download and print out so that you can go see your GP well informed, I found that when I did that I got a completely different story!

    My cardiologist suggested aspirin because my CHADS score was 0 - you can check yours on line before you go to GP - but as soon as I saw an EP he said anticoagulant, the EP's are the electricians of the heart and their specialist knowledge is the only opinion I go by.

    Good luck, you we have all been were you are now and are here to support you, you can travel safely...... Good luck and take care.... X

  • I forgot to say, my GP now acknowledges that I may know more than he when it comes to AFib!

  • Aawww thank you all so much for the lovely support and help and Varina8 I was told by my EP I have no other condition as all scans were clear, but he said that clopidrogel will be ok for me. And that's why even he did not put me on warfarin. So my PAF is fine and like I said I have not had another episode since last September. It did leave me feeling very anxious though in the beginning. Now I am ok and I was discharged from the cardio clinic at the beginning of February 2014 by my EP. He thinks it's the menopause that is giving me palpertations that set my AF off. But now fine with the beta-blockers. So hopefully I will get on that flight. Although have got a very busy year as my son Is getting married in August. Then looking forward to a lovely holiday in November. But thank you all you all are like my AF family. :)

  • hi sweetsugar

    my chad score is 0 and my cardio took me off warafrin and put me on aspirin four months ago.the more i read the more i get confused. i feel its about time that someone from the top end of the medical profession came on this site and put to bed this very serious issue once and for all. i cannot believe that my professor cardiologist would be totally ignorant to the point of putting me at risk of a stoke.

  • Why do you say blood clot in your leg as opposed to anywhere else ?

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