New to Coumadin and vitamin K

[Lawdog]

I have had an ON-X installed since Summer 2015. I was 40 at the time of my surgery, so I wanted the value that would allow me to remain active and to worry the least about the very real side-effects of anticoagulation therapy. Post-surgery, my physicians approved a PT/INR range of 1.5 to 2.0. Despite the lower range, I insisted on, and continue to maintain, an INR range of 1.5 to 3.0. I keep excellent records of my INR testing, and since late 2015, my actual INR results have has been as low as 1.6 and as high as 2.8. Personally, I target 2.0 and have been successful maintaining it, with occasional swings, through a healty diet and my daily 5 mgs tablet of warfarin.

 

[Protimenow]

I don't think your life would change if you maintain a range of 2.0 - 3.0. Depending on the meter you use to self-test, a reading of 1.6 may actually be 1.4 at the lab (not that labs always get it right - they don't).
If it was me, and I had an On-X instead of my now old St. Jude's valve, I'd be much more comfortable with an INR above 2.0.

 

[Keithl]

I have an On-X 15 weeks ago, surgeon said at this point I can do 1.5-2.0 which I am not comfortable with at all. I do take 81mg aspirin and 2x1400mg fish oil (1800mg Omega-3) every day so those 2 items help with lowering clotting so I am comfortable with the 2.3 - 2.6 target and the Carido has me listed as 2.0 - 3.0.
As Protimenow stated your meter will be off a little (lass on low end possibly more on high end) so give yourself some buffer space. @.0 vs. 3.0 is little if no difference in lifestyle. Also if you look at the stats for events at a particular INR the safest range is 2.5- 2.9 wither side of that and the events per 100 years increases slightly.

 

[Protimenow]

The CoaguChek XS often gives a reading that is higher than an accurate lab reading.

The Coag-Sense (I use the new model, the PT2, which I strongly recommend) usually reports slightly lower than labs. Personally, I'm more comfortable with a reading that is lower than the lab's - if the PT2 says my INR is 2.0, I am comfortable that it's between 2.0 and the 2.2 or 2.3 that a good lab will report.

A target range of 2.3 - 2.6 is too small to hit much of the time - it would be easier to go for a broader target - perhaps 2.3 - 3.0, or something like that.

As long as you continue with the same amount of Fish Oil daily, and adjust your warfarin dose for that daily dose of Fish Oil, you should be fine. If you reduce your Fish Oil intake, it's possible that you may need more or less warfarin. Be aware that sometimes our INR changes even though we haven't done anything that we know of that made it change. It just happens.

Also - if you don't already have a meter, and do weekly testing, I suggest that you start as soon as your INR is stable. (And I've already mentioned which meter I prefer, so I won't repeat it).

 

[Keithl]

Agreed. I target 2.3 to 2.6 but if I get a swing outside my target, but in my range I am fine. The fish oil has not seemed to have an impact yet, been back on it 2 weeks. I believe the NCBI study showed fish oil doses under 3 grams had no impact on INR. This is why I phased in my supplements weeks apart to give my body time to settle in to the supplements and see if any INR impact.

I love my CoagSense PT2, awesome meter and seems very accurate.

 

[dick0236]

My range is and has been, since the inception of the INR system 2.5-3.5 and I prefer staying just under 3 but anywhere in my range is OK. I haven't had a stroke since1974, years before the INR system, when anticoag management was pretty much done by "seat of the pants". I have never had an uncontrolled bleed even tho I have had a bunch of stitches over the years. I have taken 35-37mg per wk for years and seldom make more than minor adjustments. This evening, for the helluvit I pulled my recent INRs off the computer. Since 10/2012 to 8/2019 I have self-tested 406 times. 41<2.5, 38>3.5 and 327 2.5-3.5.........that's 81% in range......well within acceptable limits. BTW, there have been only 5 tests above 4.0 and only 1 test under 2.0.........and I do not let the tail (warfin) wag the dog (me). INR management is real simple......."take the pill as prescribed, test routinely and live your normal life". Over the 11-12 years I have been on this forum warfarin management gets way to much "ink".........it ain't rocket science.

 

[pellicle]

I have an On-X 15 weeks ago, surgeon said at this point I can do 1.5-2.0 which I am not comfortable with at all.

well just because they give you premission doest not mean you must do that. You can quite easily direct your manager to maintain your level between 2 and 3

 

[pellicle]

The CoaguChek XS often gives me a reading that is higher than an accurate lab reading.

I fixed your typo ;-)

because it give "me" a reading which is often exactly what my lab gives me

 

[Protimenow]

I didn't underline of bold the ME because I thought I was being obvious that it was a personal statement.

It's good to see that your meter agrees with your lab results - maybe our labs are just getting weird reagents - perhaps your lab is taking a shortcut and using a CoaguCheck XS for THEIR testing. (This should be easy to tell -- if they give you a prothrombin time that is expressed down to tenths of a second, they're not using a meter.)

 

[pellicle]

I didn't underline of bold the ME because I thought I was being obvious that it was a personal statement.

nor did you write ME ... which I felt was an important word to change the meaning from the infinitive to the personal.

you wrote:

The CoaguChek XS often gives a reading that is higher than an accurate lab reading.

to an ordinary reader this is not ambiguous and is not related to your experience. I challenged this as (especially you being someone who once edited science papers) its not correct and needs a qualifier which you did not provide (and then clearly forgot you didn't). As I often quote, this publication from Roche shows it can read under or over depending on reagent.

 

[Protimenow]

I must have missed the 'me.' Thanks for catching it.

And, yes, the reagent values must be accurate so the tests are accurate. I've found many labs where the INR didn't match the prothrombin time -- In the past, I've had quite a few tests where the prothrombin time on my meters matched the lab almost exactly - but the INRs were a few points off. I was thinking that if the prothrombin times matched - meter to lab - the reagent values should also be similar - and, so the INRs should match. They didn't. I assumed that the value for the lab's (or my strips) had to be different, resulting in a slightly different INR.

Fortunately, this stuff is not exact - lab nor meter - and we take the values as a range, with accuracy around 20% either way.

 

[Keithl]

Actually I referenced wrong report, it was a JAMA report that should events at a given INR range.


https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/415179
A section of that report;

The lowest incidence was found at an INR of 2.5 to 2.9: 2.0 per 100 patient-years (95% CI, 0.2-5.7). At higher INRs (≤4.5), incidence rates increased only slightly to a maximum of 2.6 events per 100 patient-years for an INR of 4.0 to 4.5. In contrast, incidence rates rose rapidly from 6.7 per 100 patient-years (95% CI, 0.6-19.4) for an INR of 2.0 to 2.4, up to 51.8 per 100 patient-years for an INR of 1.0 to 1.4, and from 4.7 per 100 patient-years (95% CI, 1.4-9.8) for an INR of 4.5 to 4.9, up to 55.3 per 100 patient-years (95% CI, 28.0-91.9) for an INR greater than 5.5.

 

[user 15848]

I have an OnX since 2015, and my target number is always 2.2; that gives me a safety fluctuation range from 1.9 to 3. Onx says you can keep it between 1.5 and 2, but i dont want the risks of low INR; Warfarin and ASA 81 is just like drinking morning expressos for me, not the boogie man i used to think 3 months before surgery ( Thanks Pellicle, you helped a lot in my valve choice decision), and i am happy to know that there is a very remote probability of needing a second OHS in my life time, i was 62 when had the OnX,

 

[tom in MO]

I have no problem maintaining an INR between 2 and 2.5, so it's possible to be in range with a 0.5 INR window.

My cardiologist put me on fish oil pre-AVR but had me go off post-AVR. He indicated it wasn't needed and is contraindicated if one is on warfarin. My cardiology group was big on fish oil for awhile, one of the members sells the stuff. They have since stopped pushing it. So if you are taking it for heart problems, per NIH's website: Research indicates that omega-3 supplements don’t reduce the risk of heart disease. However, people who eat seafood one to four times a week are less likely to die of heart disease. So I try to eat seafood at least twice a week. It's better for you than swallowing a magic pill.

Per NIH's website: If you’re taking medicine that affects blood clotting...consult your health care provider before taking omega-3 supplements.

There is no such thing as a "target INR number." The science of anticoagulation and the accuracy of the INR test (either by lab or at home) precludes the setting of a number. It is always a target range and per my clinic a few points one way or the other is nothing to sweat about or even make an adjustment other than to test in a week to see if it is a trend. That's because it's not a target number but a target range. My cardiologist group has one doctor who specializes in anticoagulation and from my experience they do a good job.

 

[Protimenow]

Actually I referenced wrong report, it was a JAMA report that should events at a given INR range.


https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/415179
A section of that report;

The lowest incidence was found at an INR of 2.5 to 2.9: 2.0 per 100 patient-years (95% CI, 0.2-5.7). At higher INRs (≤4.5), incidence rates increased only slightly to a maximum of 2.6 events per 100 patient-years for an INR of 4.0 to 4.5. In contrast, incidence rates rose rapidly from 6.7 per 100 patient-years (95% CI, 0.6-19.4) for an INR of 2.0 to 2.4, up to 51.8 per 100 patient-years for an INR of 1.0 to 1.4, and from 4.7 per 100 patient-years (95% CI, 1.4-9.8) for an INR of 4.5 to 4.9, up to 55.3 per 100 patient-years (95% CI, 28.0-91.9) for an INR greater than 5.5.

Incidence of WHAT? (I'm editing this - this was for 'INR-specific incidence rates of all combined untoward events and their 95% CI per INR level.'

This report was on a Dutch population at a clinic, from 1994-1998. According to the paper, at that time, the recommended range for prosthetic valve patients was 3.0 - 4.0. This range was lowered based on research taht indicated a lower INR was effective.

The study conclusion said that an INR of 3.0 was optimal. The study showed the best outcome for prosthetic valve patients to be between 2.5 and 2.9. On-X valves weren't available then. Improved prosthetic valves from other manufacturers also didn't figure in.

It should be obvious that maintaining a high INR (above 4.5 or so) or an INR from 1.0 - 1.5 (actually, anything below 2.0) would be dangerous for any person with a prosthetic heart valve. INR above 4.5 would not be good for anyone - whether or not they have a prosthetic valve.

Personally, I try to keep my INR ALWAYS above 2.0, usually above 2.5, and always below the high 3's. For me, a range of 2.5-3.0 is a target - unless I need blood drained from a cyst (or something), I don't have a problem with the INR going just slightly above 3.0.

 

[Keithl]

True, but look at On-X their study was like 1100 people, not enough to convince me to go below 2.0. I like being in the mid 2’s, I don’t freak out when I hit 3.1 or 3.3 on rare occasion.

 

[pellicle]

True, but look at On-X their study was like 1100 people, not enough to convince me to go below 2.0.

nor me ... what it does suggest however is that should you find yourself at (say) 1.7 its not a "panic stations hit the heparin quick" event, but just take one dose of (say) 40% more than usual, continue on perhaps usual or perhaps 10% or so more and retest as usual next week.

 

[pellicle]

I have no problem maintaining an INR between 2 and 2.5, so it's possible to be in range with a 0.5 INR window.

its possible for YOU but may not be for everyone ... just because (even if it was) the majority have such little variation (and polls here over the years suggest otherwise) some do not. So for them its practically impossible to maintain a window of 0.5, which is why its (for them) better to shoot for their mean or "target" INR (which for Aortic position mechanical is usually 2.5 (and manage the variations as they come.

 

[pellicle]

Actually I referenced wrong report, it was a JAMA report that should events at a given INR range.

which is the source of the file I so often post here:

 

[Protimenow]

The results that were posted by Pellicle suggest that it's actually safer (fewer events) at an INR from 2.5-2.9, and is still safer at 3.0-3.4 than it is with an INR of 2.0- 2.4.

If this is the study that I think it is, the results relate to a group studied from 1994-1998. This was the days before On-X and probable improvements in the other valves since then. Still, keeping INR between 2.5 and 3.5 (or 2.0 and 3.5) is probably the most protective range.