Warfarin is the gold standard for comparing the never anticogulant drugs for their therapeutic efficacies.It is time tested, efficacy established by multiple randomized trials and cost effective. Though it has narrow therapeutic range and has higher chances of IC bleeds vis a vis dabigartran, the latter is costly and not yet an established therapeutic alternative to the former.

Thanks a lot dear Mohammed Akbar Bhat ·for kindly responding me. I agree with you. Thanks a lot.

Anticoagulants Other Than Warfarin for Atrial Fibrillation

Examples

Generic Name-Brand Name

apixaban -Eliquis

dabigatran -Pradaxa

rivaroxaban -Xarelto

How It Works

Anticoagulants prevent blood clots and keep blood clots from getting bigger. They are also called blood thinners.

Apixaban and rivaroxaban block a blood clotting factor (Factor Xa) from working. Clotting factors are substances that make blood clot.

Dabigatran keeps thrombin from making a blood clot. Thrombin is a substance (enzyme) in the bloodstream that is needed for blood to clot.

http://www.webmd.com/heart-disease/atrial-fibrillation/dabigatran-for-atrial-fibrillation

Also see this paper

Article Dabigatran versus Warfarin in Patients with Atrial Fibrillation

Thanks a lot Dr. Aldallal.

The NOVEL thrombolytics are less patient intensive compared to warfarin which requires frequent monitering and adjustments plus increased bleeding risks. 

Its needs more time to asses risks and efficacy , as well as fact that most prescribers are bit reluctant with them.

Dabigatran 150 mg bid is the only NOAC proven to be superior to warfarin for the primary efficacy endpoint of stroke and systemic embolism in patients with non-valvular AF, with no significant difference in the primary safety endpoint of major bleeding. Dabigatran 110 mg bid was non-inferior to warfarin with 20% fewer major bleeds (RE-LY trial).

http://www.nejm.org/doi/full/10.1056/NEJMoa0905561

For the prevention of thromboembolism in non-valvular AF in patients with a CHA2DS2-VASc ≥ 2, the European Society of Cardiology Guidelines recommend OAC treatment with adjusted-dose VKA (INR 2-3) or a direct thrombin inhibitor (dabigatran) or an oral factor Xa inhibitor (e.g. rivaroxaban, apixaban) (Class I, Level A).

For the prevention of thromboembolism in non-valvular AF in patients with a CHA2DS2-VASc = 1, the European Society of Cardiology Guidelines recommend that OAC treatment with adjusted-dose VKA (INR 2-3) or a direct thrombin inhibitor (dabigatran) or an oral factor Xa inhibitor (e.g. rivaroxaban, apixaban) should be considered, based upon an assessment of the risk of bleeding complications and patient preferences (Class IIa, Level A).

For patients with valvular AF the recommended oral anticoagulant therapy is VKA.

http://eurheartj.oxfordjournals.org/content/ehj/33/21/2719.full.pdf

http://www.nejm.org/doi/full/10.1056/NEJMoa0905561

http://eurheartj.oxfordjournals.org/content/ehj/33/21/2719.full.pdf

Warfarin is the gold standard therapy for prevention of stroke in atrial fibrillation. As Re-Ly study showed dadigatran 150 mg bd is superior to warfarin in stroke prevention but increased risk of bleeding whereas dabigatran 110mg bd dose was non-inferior to warfarin with less risk of bleeding. So, if the patient on warfarin  is stable with expected INR  , there is no need to change to dabigatran. In our country, rivaroxaban gains acceptance to the physicians for prescribing in patients with non-valvular AF as the  INR estimation is not easy test to be done. But for AF in mitral valvular diseases , so common in our country, warfarin - time tested drug - remains the choice.

Once again, I have to agree with Mohammed Akbar Bhat and also with Guillermo Alberto Perez Fernandez. Despite its adverse events, warfarin remains the appropriate choice for two main reasons: it can be monitored through INR testing and can be counteracted by Vitamin K. This is not available for the so called "alternative drugs". They are currently fashionable but not necessarily better.

First, despite warfarin can be monitored the time in therapeutic range (TTR) is low even in patients monitored in anticoagulation clinics. Here are two recent publications on this matter

http://content.onlinejacc.org/article.aspx?articleid=1760636

http://www.ncbi.nlm.nih.gov/pubmed/26093875

Second, dabigatran has a reversal agent named idarucizumab.

http://www.nejm.org/doi/full/10.1056/NEJMoa1502000

The issue of unaffordability is slowly fading out.................however no definite guidelines on use of dabigatran in valvular af.

I prefer Dabigatran in AF treatment. 

1. There are two doses for potential usage. We can use 110 mg to decrease bleedng complication or 150 mg to increase the efficiacy.

2. Idarucizumab seems as a safe and effective agent to reverse bleeding side effects.

Dabigatran 150 bid is superior to warfarin with the same risk of bleding. 110 bid is non inferior to warfarin with less bleeding complications 

Be sure this is nonvalvular Af because warfarin is the only choice in valvular Af.

Especially considering the data of RE-LY trial, one should be careful to start dabigatran in patients pre-disposed for myocardial infarction and gastric intolerance. further,

A dose of 150mg twice daily is recommended in order to work for patients with a creatinine clearance >30 mL/min, whereas in patients with severe renal insufficiency (creatinine clearance 15–30 mL/min) the approved dose is 75 mg twice daily. There are no dosing recommendations for patients with creatinine clearance

With the reversal agent, idarucizumab, being available, dabigatran is preferable to warfarin for preventing stroke in patients with atrial fibrillation for reasons given above. However, it cannot be overemphasized that dabigatran is 85% excreted in the kidney; its dosing should be adjusted according to eGFR. For a 90-year-old patient, especially women, 110 mg QD or 75 mg BID might suffice for the purpose.

Dabigatran is preferable to warfarin. 3 patients experienced with Warfarin coagulopathy were admitted in our hospital. One had Valvular AF, other patient had DVT with pulmonary embolism and the third one post mitral valve replacement and they were on warfarin. After reversing the effects of warfarin we started them on Pradaxa depending on their weight. One of the patients is on 220mg (max. dose). All of them are doing well with no bleeding manifestations, also Idarucizumab a reversal agent is available So, I suggest Dabigatran over warfarin though its costly. Dose reductions should be done in ESRD and avoid coadministration with P gp inhibitor.

I don't use the NOACS, because even now ther's not a large scale outpatient valuable method of monitoring the anticoagulant activity of these drugs. I don't believe in the common saying that " NOACS don't require monitoring of anticoagulant activity", because I'm not aware of any drug free from metabolic variability. In a so thorny and potentially dangerous therapy like anticoagulant one, I would not be sure and confident in using "blindly" an anticoagulant, particularly in NVAF. Even if TTR of Warfarin was 60-65%, it would be anyway better than the inability of exactly know the level of anticoagulant activity.  Sincerely yours   Vittorio Dall'Aglio

Anticoagulants Other Than Warfarin for Atrial Fibrillation

Examples

Generic Name               Brand Name

    apixaban                         Eliquis

   dabigatran                      Pradaxa

   rivaroxaban                     Xarelto

How It Works

Anticoagulants prevent blood clots and keep blood clots from getting bigger. They are also called blood thinners.

Apixaban and rivaroxaban block a blood clotting factor (Factor Xa) from working. Clotting factors are substances that make blood clot.

Dabigatran keeps thrombin from making a blood clot. Thrombin is a substance (enzyme) in the bloodstream that is needed for blood to clot.

Why It Is Used

Anticoagulants are used to lower the risk of stroke and blood clots in people who have atrial fibrillation.

Apixaban, dabigatran, and rivaroxaban are newer medicines than the anticoagulant medicine warfarin. Warfarin has been used for many years to help prevent stroke in people who have atrial fibrillation. If you are thinking about taking a newer anticoagulant instead of warfarin, talk with your doctor to see if it is right for you.

Reasons why you might take an anticoagulant other than warfarin include:

You cannot take warfarin safely, such as not being able to keep a safe level of warfarin in your blood (INR).

You have side effects from warfarin that are hard to live with.

You do not want to have to get regular blood tests and watch how much vitamin K you eat. Both are needed if you take warfarin.

You cannot take apixaban, dabigatran, or rivaroxaban if you have heart valve disease, an artificial heart valve, or severe kidney or liver disease.

Atrial Fibrillation: Which Anticoagulant Should I Take to Prevent Stroke?

How Well It Works

These anticoagulants lower the risk of stroke in people who have atrial fibrillation.1, 2, 3

How much your risk for a stroke will be lowered depends on how high your risk was to start with. Not everyone who has atrial fibrillation has the same risk of stroke. It's a good idea to talk with your doctor about your risk.

You will want to weigh the benefits of reducing your risk of stroke against the risks of taking an anticoagulant. Anticoagulants can help prevent stroke. But this medicine also raises the risk of bleeding. Your own risk of bleeding may be higher or lower than average, based on your own health.

Side Effects

All medicines have side effects. But many people don't feel the side effects, or they are able to deal with them. Ask your pharmacist about the side effects of each medicine you take. Side effects are also listed in the information that comes with your medicine.

Here are some important things to think about:

Usually the benefits of the medicine are more important than any minor side effects.

Side effects may go away after you take the medicine for a while.

If side effects still bother you and you wonder if you should keep taking the medicine, call your doctor. He or she may be able to lower your dose or change your medicine. Do not suddenly quit taking your medicine unless your doctor tells you to.

http://www.webmd.com/heart-disease/atrial-fibrillation/dabigatran-for-atrial-fibrillation

I just saw a paper about using human genome and genetic profiling in clinical practice and I bring that up here because I have a warafin genetic problem that makes me more prone to bleeding.   I had surgery with no problems and very little bleeding.   I was given heprin to prevent blood clots after and proceeded to interally bleed almost half my blood.   I did 23andMe about a year ago, after the surgery and recovery.   Anyway I just thought I would add that I think it is time for genetic testing to be a standard part of screening. 

I would highly recommend to read my 2 co-authored articles mentioned below. If u need the full manuscript, feel free to write to me.

Phan K, Wang N, Pison L, Kumar N, Hitos K, Thomas SP: Rivaroxaban versus warfarin or dabigatran in patients undergoing catheter ablation for atrial fibrillation: a meta-analysis. International journal of cardiology Int J Cardiol. 2015 Apr 15;185:209-13.DOI: 10.1016/j.ijcard.2015.03.102

Phan K, Wang N, Pison L, Kumar N, Hitos K, Thomas SP: Meta-analysis of dabigatran vs warfarin in patients undergoing catheter ablation for atrial fibrillation. International journal of cardiology 04/2015; DOI:10.1016/j.ijcard.2015.04.072