A Clearinghouse for Information about Blood Clots (DVT/)PE) and Clotting Disorders (thrombophilia) provided as a public service by the University of North Carolina Blood Research Center

DVT and PE: How Long to Treat with “Blood Thinners”

What Kind of Clot did You Have?

If you have had a blood clot in your legs or your lung (pulmonary embolism=PE), you will wonder how long you should stay on a “blood thinner”. The decision depends on a number of factors which will be discussed below.

  • First, you and your doctor will want/need to know where in the extremity the clot was, as this influences management: Was it (a) a superficial clot (= superficial thrombophlebitis; surface clot) or was it a DVT (deep vein thrombosis; clot in the deep veins of the leg or pelvis)?
  • If you had a DVT you will want to know: was it in the veins below the knee (=distal DVT) or in the veins in your thigh or pelvis (= proximal DVT). The anatomy of leg veins is shown here.

This blog entry will discuss management of leg DVT and of PE.  Management of DVT of the arms and superficial thrombophlebitis will be discussed in separate blog entries.

Risk-Benefit Assessment

Whether short-term or long-term “blood thinners” should be given depends on:

  • (a) How high the risk of another clot is if the person comes off “blood thinners”, and (b) the risk of bleeding if the person remains on them. Thus, the decision to continue or discontinue “blood thinners” is a risk-benefit assessment: risk of a new clot off “blood thinners” versus risk of bleeding on “thinners”.
  • In addition, it is important to take into consideration the patient’s preference, i.e. whether he/she minds being on a “blood thinner” (fluctuating or stable INRs?; frequency of clinic visits for INR monitoring; expense of the drug and clinic visits; impact of being on blood thinners on profession and hobbies; side effects).

If the risk of another clot is low, then short-term treatment for only 3 months is sufficient. This is long enough for the present clot to heal. However, if the risk for another DVT or PE is high, then treatment for more than 3 months is appropriate. This typically means long-term treatment, i.e. for several years.  However, reevaluation in clinic once per year is appropriate to see whether continuation of the “blood thinner” is still the right thing to do.

Length of Treatment

A.  Provoked leg DVT or PE

a)      Provoked by a major temporary risk factor
3 months of “blood thinners” are typically all that is needed if a DVT (no matter whether distal or proximal) or PE was associated with a major transient risk factor, such as

  • major surgery
  • hospitalization
  • prolonged immobility (more than 3 days of bedridden state; cast or immobilizer after a bone fracture)
  • major trauma
  • long-distance airline travel (fights more than 12 hours).

Once off  “blood thinners”, the risk for future DVT or PE is low. Less than 5 % (i.e. less than 1 out of 20) of these patients will develop another clot over the next several years [ref 1].  In this situation, no wok-up for a clotting disorder (thrombophilia) needs to be done, because the treatment would still only be 3 months, even if a thrombophilia was detected.

b)      Provoked by a minor temporary/transient risk factor
Treatment decisions are more difficult if the DVT or PE was associated with a minor risk factor only, such as

  • minor trauma
  • minor surgery (e.g. arthroscopic surgery, plastic surgery)
  • birth control pill, patch or ring or other estrogen therapy
  • pregnancy
  • less than 12 hour airline travel.

In these patients treatment with “blood thinners” for 3-6 months may be all that is needed. However, the risk of another clot in this group of patients may be higher than in the group mentioned above who had a strong triggering factor. It is this “gray zone” group of patients with some intermediate risk of recurrence where length of treatment decisions are difficult. Presence of additional risk factors for recurrence (overweight, presence of postthrombotic syndrome, positive D-dimer test results, age > 65, strong thrombophilia) might argue for longer-term “blood thinners”, absence of such risk factors for discontinuation.

B.  Unprovoked DVT or PE

If a DVT of PE occurs out of the blue, without any clear triggering factor, it is referred to as unprovoked or “idiopathic” DVT or PE. The length of “blood thinner” treatment in the case of leg DVT depends on where in the leg the DVT was – distal (below the knee) or proximal (behind the knee or in the thigh or groin).

a) Distal DVT (i.e. below the knee, in the calf). Length of treatment is typically 3 months only [ref 2].

b) Proximal DVT (pelvis, thigh, and/or behind knee) or PE
At least 3-6 months of “blood thinners” are typically recommended, with a preference for long-term treatment, if the patient tolerates therapy well [ref 2,3]. There have been attempts to identify which of these patients have a higher and which have a lower risk of recurrence, i.e. in whom one can safely discontinue “blood thinners” and who clearly needs long-term therapy. Unfortunately, for some of these determinants, data from clinical studies are not very solid or too premature. Sometimes, different studies have provided discrepant results. This is a field of knowledge that is changing rapidly. Possible determinants of a higher risk for future clots are:

  1. Gender (men have a higher risk for recurrence than women)
  2. Presence of a strong clotting disorder – see table (Strong thrombophilias)
  3. Obesity
  4. Significant chronic leg swelling (postthrombotic syndrome)
  5. Positive D-dimer blood test obtained while the patient is still on the “blood thinner”
  6. Positive D-dimer blood test obtained 4 weeks after having come off the “blood thinner”
  7. A lot of left-over (residual) clot on follow-up Doppler ultrasound examination of the leg.
  8. Strong family history of unprovoked DVT or PE.
  9. In addition, patients who had a PE more likely have a PE as a recurrence and have a higher risk of dying from the recurrent clot, compared to patients who “only” had a DVT.

The image (How long to treat) shows how I approach the length of “blood thinner” therapy decision in 2011. In men with an unprovoked DVT or PE, I have a tendency to recommend long-term “blood thinners”, particularly if the clot was a PE. In women who had a DVT or PE,  it would be reasonable to consider discontinuation of “blood thinners”, if the woman is of normal weight, does not have postthrombotic syndrome, is less than 65 years old , and has a negative D-dimer.

C. Recurrent DVT or PE

If a patient has had 2 or more clots long-term “blood thinners” are not automatically needed. The decision how long to treat still depends on what triggered each of the episodes of DVT or PE.

  • The patient who had 2 episodes of DVT or PE, each associated with a major transient risk factors, such as surgery, will not need to be on long-term “blood thinners; he/she “just” needs very good DVT prophylaxis in the future after major surgeries.
  • However, the person who has had 2 episodes of unprovoked (idiopathic) DVT or PE, clearly shows that he/she “likes” to clot. In that person, long-term “blood thinners are clearly needed.

What does “Long-Term” Therapy Mean?

It means treatment for many years to come, but reevaluation once per year, to see whether continuation of “blood thinner” therapy is still the right thing to do in this patient. Things to consider and discuss with your thrombosis doctor at such an annual follow-up visit are:

  • How have you tolerated the “blood thinner” in the last year? Have you had bleeding problems or any new clots?
  • If you are on warfarin, have your INRs (blood test to measure how “thin” your blood is) been up and down and unsteady/fluctuating, or very steady? How often do you need to get your INR tested?
  • What new studies have come out that might tell us who is at low risk for a future blood clot and who is at higher risk if off “blood thinners”?
  • Is it unacceptably expensive for you to be on a “blood thinner” or getting it monitored?
  • Do you mind being on a “blood thinner” and what is your own preference regarding
  • being on it or not?
  • Have new “blood thinners” been FDA approved and are they now available? Might they be suitable for you to switch to?
  • Are there any DVT or PE studies that you could enroll into? To stay up-to-date you can sign-up for the monthly Clot Connect Newsletter, check the “research to participate in” section (in development) of the Clot Connect website or check the NIH clinical trials website.

Does having a thrombophilia (clotting disorder) mean that I should be on long-term “blood thinners”?

 

Decisions on how long to treat a patient with “blood thinners” are often independent on whether a thrombophilia is present or not. The decision is typically primarily based on the circumstances of the first clot (DVT or PE), i. e. whether it was triggered by a temporary risk factor or whether it was unprovoked (= idiopathic).  If the clot was triggered by a major temporary risk factor, such as major surgery, then 3 months of therapy are sufficient. This is also true, if a mild clotting disorder, such as heterozygous factor V Leiden or heterozygous prothrombin (=factor II) 20210 mutation, is found. In patients with unprovoked (idiopathic) DVT or PE on the other hand, long-term “blood thinners” are often recommended, and this recommendation is the same, no matter whether a thrombophilia is present or not.

One of the few times that finding a thrombophilia really makes a difference in the “blood thinner” treatment of a patient is in the following two scenarios: (a) If a patient had a DVT or PE associated with a mild risk factor (such as birth control pill), the finding of a strong thrombophilia (see table) may lead to long-term therapy with “blood thinners”; whereas finding of no thrombophilia or only a mild thrombophilia (such as heterozygous – i.e. one variant gene –  factor V Leiden or heterozygous II20210 mutation) may lead to discontinuation of “blood thinners” after 3-6 months; (b) in the patient with unprovoked DVT or PE who does not tolerate warfarin, very much dislikes being on it, or is thought to have a lowish risk of recurrence (women with DVT only) – see the image (How long to treat):  in these patients the finding of a STRONG thrombophilia would be a reason to continue “blood thinners”, while the finding of no or only a mild thrombophilia might lead to discontinuing them.

The Risk-of-Recurrence and Risk-of-Bleeding Calculator

It would be nice to have a web-based calculator into which one could enter a patient’s clinical details about the first clot, the patient’s risk factors for recurrent clot as well as for bleeding, so that the calculator would spit out a risk-benefit assessment whether this patient should remain on “blood thinners’ or come off. At present there are not enough data from good, solid, prospective clinical trials to make such a calculator reliable, but increasingly such data are being published [ref 6,7]. At some point in the future such a calculator will likely become reality.

Existing Guidelines for the Treatment of DVT and/or PE

Well respected treatment guidelines have been published for health care professionals 1,2, developed by a panel of national and international experts who reviewed all published clinical trial data and came up with evidence based treatment recommendations.

  • The comprehensive ACCP (American College of Chest Physicians) guidelines are highly valued[ref 2]. They are brought up-to-date every 3-4 years. The next update is slated to be published in 2012.
  • A brand new, very solid, yet less comprehensive guideline (does not cover DVT of the mid-thigh, or distal leg; does not cover superficial thrombophlebitis) has just been published by the American Heart Association[ref 3].
  • For many health care providers, these guidelines are a little cumbersome to use in clinical practice, due to their extensiveness and complexity. Solid down-to-the-point, practical “How-to” summaries have, therefore, been published [ref 4,5].

Key Points for the Patient

  • Know whether you had a superficial clot (superficial thrombophlebitis) or a deep vein clot (DVT).
  • If you had a DVT, know whether it was below the knee (=distal) or behind and/or above the knee (=proximal DVT).
  • If you are not sure what kind of clot you have/had and where in the leg it was, print out this leg vein anatomy drawing and ask your health care professional to mark where your clot is/was.
  • Know the risk factors that triggered your clot.
  • Ask your health care professional how long he/she thinks you should be on “blood thinners”.
  • Ask whether obtaining a D-dimer would be helpful, a thrombophilia work-up, a repeat Doppler ultrasound of the leg to look for residual clot.
  • Find out whether there are any clinical studies you could participate in.
  • If you are on long-term “blood thinners”, rethink once per year with your physician whether you should still be on it. Inquire about new studies published, new “blood thinner” drugs available.

Patient Questions /Examples – Explanations

Question #1: “I have been told that I need to be on blood thinner for life. I have factor V leiden….Is this the truth????????”

Answer #1: The questions you should ask your doctor are clear: (a) did I have a proximal DVT or PE, or only a distal DVT? (b) what were the triggering factors for my clot (immobility, surgery trauma, long-distance travel, etc)?, (c) what clotting work-up was done beside of factor V Leiden?, (d) do I have one or two abnormal genes for factor V Leiden, i.e. am I heterozygous or homozygous?. Once you have this information, you often have an inkling on whether it is appropriate to be on long-term “blood thinners” or not, based on published guidelines and, hopefully, the preceeding discussion in this Clot Connect blog entry. You should also ask your physician: (e) What is my risk of recurrent clot if I am off “blood thinners”?, (f)) how long should I be on “blood thinners”?, and you might ask: (g) is it worthwhile for me to be referred to a Thrombosis Center for specialist input?.

References

  1. Iorio A et al. Risk of recurrence after a first episode of symptomatic venous thromboembolism provoked by a transient risk factor: a systematic review. Arch Intern Med. 2010 Oct 25;170(19):1710-6. Review.
  2. Kearon C et al. Anithrombotic therapy for venous thromboembolic disease. American College of Chest Physicians evidence-based clinical practice guidelines (8th edition). Chest 2008;133:454S-545S.
  3. Jaff MR et . Management of massive and submassive pulmonary embolism, iliofemoral deep vein thrombosis, and chronic thromboembolic pulmonary hypertension. AHA A scientific statement from the American Heart Association. Circulation 2011;123:pre-published on the web.
  4. Bauer K. Duration of anticoagulation: applying guidelines and beyond. Am Soc Hematol Education Program Book 2010;210-215.
  5. Goldhaber SZ et al. Optimal duration of anticoagulation after venous thromboembolism. Circulation 2011;123:664-667.
  6. Rodger MA et al. Identifying unprovoked thromboembolism patients at low risk for recurrence who can discontinue anticoagulant therapy. CMAJ 2008;179:417-426.
  7. Eichinger S et al. Risk assessment of recurrence in patients with unprovoked deep vein thrombosis or pulmonary embolism: the Vienna prediction model. Circulation. 2010 Apr 13;121(14):1630-6

Disclosure:  I have no relevant financial conflict of interest with this blog entry.

Last updated: March 31st, 2011

Stephan Moll

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23 responses to “DVT and PE: How Long to Treat with “Blood Thinners””

  1. I was diagnosed with a PE; I was 8 weeks pregnant. Is it likely that it can just be a one time thing or should I expect more down the line? My iron was real low before I got pregnant – does low iron play a part in clotting?

  2. I had an unprovoked PE twice in a three months period and none of my ultrasounds show a clot in my legs. My doctor is suggesting a life-time blood thinner. I am 28 yrs old and I have been on blood thinner for a little more than a year now and would like to get off. What would be the smart way to get off the drug without risking another clot. A series of tests were performed and they couldn’t pinpoint any trigger for my clots. Any suggestion would help.

    • To fully understand what is going on here, one would want to know: (a) Did the patient truly have a second clot? (b) What were the circumstances of the 2nd clot – was the patient not on “blood thinners” any more?; or was the level (INR) of the “blood thinner” too low?; (c) Age of the patient; weight (body mass index); what kind of work-up for a clotting disorder was done; has malignancy (cancer) been ruled out; is there a family history of blood clots?

      In patients with one episode of unprovoked PE, the preference is to treat with long-term with “blood thinners”, if they are being tolerated well. If the patient truly has recurrent blood clots, then the patient has already shown that he/she “likes” to re-clot, and the recommendation to stay on long-term “blood thinners” is even stronger. However, before one commits a patient to long-term “blood thinners”, one would really want to be sure that what is being called a “recurrence” was, indeed, a recurrence, i.e. a second blood clot. If it was not a recurrence, then the discussion of the above blog “How long to treat with blood thinners” applies and one could discuss using the D-dimer, HERDOO-2 score, etc. for decision making.

  3. if a DVT goes from the entire leg into the inferior vena cava, does that mean it started in the IVC and extended down into the leg, or vice-versa? And if thrombosis extends into the IVC, do the typical treatments as discussed above apply, or should it be treated differently?

    • It is not clear where such extensive DVTs start – in the leg and then extend upwards, or in the IVC and then extend downwards. If the DVT is in the left leg, I wonder whether it started in the deep veins in the left pelvic due to pre-existing May Thurner syndrome. Yes, the thought process about length of blood thinner treatment decisions is similar.

  4. I had a provoked DVT in may from ACL surgery. I have also been diagnosed w/ factor V leiden heterozygote. I am a 30 year old very active male. From what I read 3-6 months of blood thinners is the recommendation, just wondering if I read that properly? My doc says 6-12 months depending but I am ready to be off them ASAP. Any ideas?

    • I suggest you discuss this with your MD. Ask why he/she recommends 6-12 months, rather than the 3 months only often given for a DVT secondary to a transient (reversible) risk factor.

      • Thanks for your help and replying so promptly. I have a meeting with my Doc this week to discuss the issues I have. Is there anything on the probability or % chance that I would have another DVT if I come off the thinners? This is the only thing that concerns me. I have read that my chances to randomly form a DVT are very slim & should only be concerned if I have a trauma or another surgery. Any thoughts on this? Anything I can take/do/eat to be as proactive as possible against this. I just want to live my life without the worry. Thanks again for your help.

        Wes

      • 1. Risk of recurrence: The risk of recurrent DVT or PE in the patient who had a clot associated with surgery and who stops blood thinners after 3 or more months of treatment is low, 1.4 % over 2 years. I.e., 1 of 70 patients develops a new clot (Iorio et al. Risk of recurrence after a first episode of symptomatic venous thromboembolism provoked by a transient risk factor. Arch Intern Med 2010;170:1710-1716]. This systematic review included patients with any type of surgery associated DVT or PE, i.e. either major or minor surgery, and the 1.4 % risk of recurrence is an average of these patients. It is possible that patients with certain surgeries have a lower or higher risk of recurrence than this average, such as that the recurrence rate is higher for those whose clot was associated with minor surgery.

        2. How to minimize future risk of DVT or PE? Good DVT prophylaxis in risk situations; normalize weight; stop smoking; not delaying diagnosis if symptoms of DVT or PE occur. Long term aspirin probably is not effective; whether natural products such as (Nattokinase) are helpful in decreasing risk is not known.

  5. I was on hormonal birth control pills for over ten years before developing a blood clot (pulmonary embolism) at the age of 28. After a harrowing experience that ended up with a week in the hospital on Heperin, I was kept on Coumadin with regular testing, etc. It’s been 5 months and my doctor has said that I’ll be on the thinners for at least a year. I can’t figure out how she has made this determination; I’m thinking about getting a second opinion. (For that and other reasons; I’m not thrilled with the competency of her office staff either.)

    I’m wondering how many other people go through this… I’m generally not scared of much, but frankly the idea of stopping the drugs, as much as I want to be finished with them, terrifies me. Does anyone know what the process is for finishing the treatment? How do I know that I won’t develop another clot from some residual chemicals from the birth control pills? I know I was lucky to feel pain before the last one; it freaks me out that I could have just dropped dead from a stroke.

    Are there any general resources for information about this? A list of good doctors? It’s so frustrating to think that I have no control over what’s going to happen to me; I’m not even 30. (On a side note, anyone else think that they should monitor young women on the potential side effects of hormonal birth control? I was never told anything about what might happen when they first prescribed the Pill for me at the age of 15.)

    • 1. “Does anyone know what the process is for finishing the treatment?”
      At the end of the 3-6 months treatment with blood thinners an assessment is made what a patient’s (a) risk of recurrent clot is if he/she came off blood thinners, and (b) risk for bleeding is if he/she stayed on blood thinners. A patient’s own preference regarding staying on or coming off blood thinners is also taken into consideration. A decision is then made to stop or continue the blood thinner. If one decides to stop blood thinners, then the patient just stops taking warfarin. It will be out of the system within approximately one week. There is no need to taper warfarin. Pradaxa is out of the system in approximately 2-3 days. I always obtain a Doppler ultrasound of the legs or arms (in case of a history of leg or arm DVT), as a baseline study. The results of this study are NOT used to help in the decision process whether to stop or continue blood thinners. But it serves as a baseline study in case future problems arise, such as recurrent extremity swelling or pain. It may then be easier to determine whether a new clot is present or whether the changes seen on a Doppler ultrasound are just old/chronic changes, i.e. scar tissue. If a patient was on blood thinners for a PE, I do not routinely obtain a CT of the chest of VQ nuclear medicine study as a baseline when the patient stops the blood thinner, because of the radiation involved with the Xray study. If the patient and I decide that he/she will continue warfarin, reevaluation once every 6-12 months is appropriate, to revisit, whether the patient should still be on a blood thinner.

      2. “How do I know that I won’t develop another clot from some residual chemicals from the birth control pills?”
      The effect of the birth control pill is out of a system within a few days or weeks. Independent of that issue, if new symptoms occur – new leg swelling, pain, warmth or redness in the extremity, or shortness of breath, chest pain, unexplained cough or fast heart rate – recurrence of a DVT or PE should be considered and the patient should seek medical attention.

      3. “Are there any general resources for information about this?”
      I hope that the comments above provide some answers. Clot Connect is also in the process of writing a brochure “Newly diagnosed with DVT or PE – What to expect”, which will take reference to the issues you raise above: the time when a patient is coming off blood thinners and the months afterwards.

      4. “A list of good doctors?”
      In the “Links to Resources” part of Clot Connect’s website you will find a section: “Find a Health Care Professional”.

      5. “Anyone else think that they should monitor young women on the potential side effects of hormonal birth control?”
      Women on birth control pills should know the symptoms of DVT and PE. They should also know their personal DVT and PE risk factors beyond the pill (obesity?, Smoking?, Family history of clots?). They should know the risk factors that increase the risk for DVT and PE (hospitalization, immobility, surgery, long-distance travel, etc.) and they should make an informed decision as to (a) whether the pill is right for them, (b) which pill is the best for them (risk for clots in highest with 3rd generation pills, less with 2nd generation pills, least with progestin-only pill or injections, not increased with Mirena IUD). And, most importantly: if symptoms of DVT or PE occur, the woman should consider that she could have a blood clot and seek medical attention. Routine screening with a Doppler ultrasound or blood tests to “discover clots before they cause symptoms” would not be useful.

      • Stephan- Thank you so much for your helpful comments and advice. I truly appreciate the time involved in your reply— I hadn’t realized there was a website connected to this blog, I’m going to do what I usually do first and read up on the information already posted here!

        I agree that women on birth control pills should be aware of the symptoms… at least, I’m aware now. When I was originally prescribed the Pill they told me, “This will help with your acne, your mood swings– and, as a bonus, you won’t get pregnant!” They never mentioned potential side effects. I hope that this has changed with doctors today, and that they take time to make sure that “invincible” teenagers understand the risks.

      • Along the lines of refraining from hormonal birth control / other HRT for those with previous clots due to birth control pills / pregnancy, is there any known reason to also refrain from soy products such as soymilk, edamame, etc.? Do the estrogen-mimicking properties of soy affect clotting the same way as estrogen does?

  6. Thank you for this hugely helpful article. This should really be a hand-out for patients who have suffered a thrombus and are wondering about their future on anticoagulants!

  7. You rarely have mentioned my thrombophilia which is elevated factor VIII. What can you tell me of long term anti-coagulation treatment after a very extensive unprovoked CVST?

    • Elevation of factor VIII is a risk factor for a first clotting event. However, it is not clear whether it predicts recurrence of clots – published data have been inconsistent. Thus, factor VIII levels are NOT a helpful tool to decide how long a patient with a clot should be treated with blood thinners. Because of the lack of clinical utility I barely ever test a patient for factor VIII levels.

      For a discussion on length of anticoagulation after a cerebral and sinus vein thrombosis, please see http://files.www.clotconnect.org/Sinus_Vein_Thrombosis.pdf.

  8. A month ago I had a complete placental abruption while in labor which resulted in my son being stillborn (3 days shy of full term). A week after his birth I was diagnosed with a PE (multiple small clots in each lobe).
    I had a completely normal pregnancy with him, and also have a healthy daughter and no history of miscarriage.

    No clots were found in my legs, and the day after his delivery I had some pelvic pain that (at the time) I described as pain in my veins, so they are fairly certain the clots originated there.

    Thus far, I have not tested positive for any clotting disorders. (antithrombin III, protein s and protein c have not yet been checked). I have no family history of clots.

    The current plan is for me to be on Coumadin for 6 months, but I feel like that timeframe was very arbitrarily decided and my hematologist has not given me a clear answer on why that is the right treatment course for me.

    I want to take medicine for as long as I need to, and not a second longer. My husband and I would like to pursue getting pregnant again and feel like the hematologist is completely disregarding that in discussing my options. Without reason, he will not discuss this until summer.

    In your experience, how long after a PE do women need to wait before pursuing pregnancy? I know that Lovenox or other treatment would likely be in my future with pregnancy, which also makes me wonder if there is a decreased risk coming off the Coumadin given I would then start Lovenox.

    We are not yet ready to face another pregnancy, but absent the PE we would have liked to considered pursuing another pregnancy 3 or 4 months out. I want to set myself up for a successful pregnancy, but with my hematologists current ‘plan’ (or lack thereof since he doesn’t listen to anything we have to say and doesn’t explain himself) it will be nearly a year before we can start trying. I am trying to determine if this is a standard timeframe after a PE.

    • (a) 3-6 months of blood thinners are often chosen for a DVt or PE associated with a trasnient risk factor such as pregnacy – https://clotconnect.wordpress.com/2011/03/30/dvt-and-pe-how-long-to-treat-with-%e2%80%9cblood-thinners%e2%80%9d.

      (b) There are no good data to tell us whether one should wait 6 months or 12 months after a pregnancy-associated clot until a woman tries to get pregnant again. Often the period during which a patient is considered to be at higher risk of recurrent clot is the first 3 months after the initial clot; 3-12 monhts is an intermediate risk period; 12 months or longer is the lower risk period. So, if a woman can wait, I would also say that waiting 12 months would be a good choice and approrpriate. However, if she cannot wait, then I’d likely be o.k with her attempting pregnancy at 6 months. She would need to be on blood thinners during the next pregnancy.

  9. My husband was in hospital and they inserted a “picc” line in his left arm. Unfortunately a blood clot, DVT developed. He is on the generic version of Aritrixa. Our question is what types of foods should be avoid so that no complications occur? He should only have to be on this injection for two more months. Thank you for any assistance you can give us.
    Best regards, Debra Wilmington

    • There are no dietary interactions with Fondaparinux. Thus, husband can eat whatever he wants.

  10. I have a provoked distal DVT (posterior popliteal vein) with a resultant small PE in the R lower lobe. I just started Lovenox and Coumadin and just reached the therapeutic INR of 2. My risk factors for the DVT/PE was 2 weeks prior to the DVT I was immobile working 12-14 hours per day sitting at my desk and then took a multi-leg flight (total 8 hours) and drove another 3-5 hours. Furthermore, I have a 20 week size uterus in need of a myomectomy which may or may not have contributed and I have a BMI of 36. I am in the health care field so when the muscle ache (that;s what it felt like in my L leg BELOW the calf) didn’t go away and I was scheduled to travel…I took the time to get ruled out for a DVT in which it and a small PE were ruled IN. No chest pain or SOB.

    I am working on the modifiable risk factors (obesity, planning a myomectomy in 6 months after anticoagulation) and increasing physical activity (no more sitting at my desk for 12-14 hours working on projects. I am concerned for the Factor V Leiden and Antithrombin II is negative. The rest of the workup will be performed at a later date. If my thrombophilia workup is negative, I lose the weight, and increase physical activity do I need to be anticoagulated for life? This is what I was told that I may need to be on Coumadin for life and when I chose to have a baby..despite the small DVT and PE I will have to take Lovenox for the entire pregnancy plus 6 weeks post partum. Please advise and is there anyone out there with a similar issue.

    • a) Correct terminology first: There is no “posterior popliteal vein”. There is either a “popliteal vein”, which is considered a proximal deep vein, or a “posterior tibial vein”, which is a distal deep vein. Leg vein anatomy and terminology are discussed in another Clot Connect blog.

      b) I think is is appropriate that this person asks whether it might be appropriate for her to come off anticoagulation after 3-6 months, particualarly if she modifies her risk factors. The blog above discusses the thought process that goes into determining who should and who should not be on longer-term anticoagulation.

      c) Regarding pregnancy in a woman with previous DVT or PE: discussed in detail in another posted Clot Connect blog.