Low INR question

[Savymom]

Hello everyone !

I just hit one year post AvR with my onyx valve. This was my second valve, the first being tissue.

3 months ago I developed a DVT in my upper extremities. My INR at the time of the clot was 2.8 ( per lab draw). My clot was likely due to my pacemaker lead, as the clot formed in that same vein. We actually removed my pacemaker and the leads, since I’ve stopped using it completely. Theoretically I’ve removed the cause of the clot in the first place. We kept my INR between 2.5-3 for a while after the clot.

However, the acc is now trying to keep my INR between 1.5-2.0 per the onyx recommended INR . I questioned them as I had a clot at 2.8 and wondered if I should keep my INR on the higher side, as a precaution. They couldn’t answer the question and basically kept saying “it’s protocol.”

My understanding is that there is no harm in maintaining a higher ( 2.5-3.0) INR , the risk of bleeding is still low correct ?

Do those of you with onyx valves maintain a lower INR ?

Do we as patients have any say in what we want our INR to be, obviously maintaining a safe therapeutic number.

In my case, I’d prefer to stay above 2.0- just in case. And if there is no harm in that, I don’t understand why they wouldn’t approve it. I suppose I can just dose myself, which may be what I end up doing anyway.

Thanks in advance for feedback with this !

 

[tom in MO]

Yes the risk of bleeding is low. Some people routinely have that INR range due to their valve type and/or location plus other reasons such as DVT.

The clinic is managing you vs. the doctors orders and it seem to them as if you are on warfarin only for the Onyx valve. I'd check with whomever upped your INR 2.5-3 for the clot. Did they change their order for the INR range back to 1.5-2 and if you personally want it higher, will they change their order?

 

[Paul1972]

Hi savymom,sorry to hear about your troubles.Ive had a onx valve for 2 years now and my inr target is between 2-3 . The surgeon who worked on me insisted on me keeping it between 2-3 where as some of his colleagues who were alot younger wanted me to target 1.5-2 and it seemed to cause a bit of conflict. It was decided to stay at 2-3 but obviously even surgeons have different ideas. Maybe my surgeon was old school but I would rather go with track records than clinical trials so if I was you I would keep with your inr of 2.5-3 or at least 2-3. All the best Paul xx

 

[LondonAndy]

I agree with Paul1972's conclusion. When people say "it is protocol" that is the "jobsworth" answer, as we call it here. (As in "More than my job is worth to think for myself - I am only obeying orders"). It is a poor defence on its own and should be supported with an explanation. Most likely they don't actually know the answer, and are simply following standard procedure without care for those of us who might not be standard (and who also have a greater interest in avoiding complications like strokes). It is not the fault of staff at this level - they are not all Cardiologists and people end up running a production line of treatment, focused on their bit of it only. You are right to strongly argue for, nay insist, on your desired treatment

Other threads here about the On-X valve have also shown some people prefer a higher INR. For myself, my INR for my St Jude aortic valve has been set at 2.5 to 3.5, and it seems to me there are more risks to health for those of us not engaging in energetic activities (at least those that pose a greater risk of injury/bleeds) from a low INR than a high one. So I prefer to keep my INR over 3.0 and if I creep over 3.5 occasionally I am not bothered.

If I fall below the lower end of my range, on the other hand, then I am very much bothered, particularly given that much though I love my CoaguChek XS for weekly home testing and freedom from clinics, I accept there is an acceptably small degree of inaccuracy about the readings that might mean the meter shows 2.4 but could actually be 2.2

 

[Protimenow]

I agree with LondonAndy and Paul. The On-X studies that are being quoted, establishing that 'safe' range were of a small sample size, and, I believe, sponsored by the manufacturers of the On-X valve.
Being able to 'safely' maintain an INR of 1.5 - 2.0 isn't much of a selling point - it's no big deal to maintain an INR between 2.0 and 3.5 (or so), and doesn't really change the lifestyle of the person who maintains an INR from 2-3 or so.
Personally, I see no advantage of having an INR from 1.5 - 2.0 - if I had an On-X, I would feel safer to have an INR in the same range as the St. Jude valves.

As far as 'protocol' is concerned, protocols are often rather stupid. I went to an Anticoagulation Clinic a few years ago. I self tested and self managed, and when I went to the clinic, I was 'Mr. Consistent' -- because I managed my INR and knew I was in range when I went to the clinic. Because my INRs were consistent, they started to extend the time between tests - from every two weeks, to every month, to every two months. All the while, I was still testing weekly. Even testing every two weeks is ill advised - 8 weeks is extremely careless. But that recommendation was 'protocol.'

If your clinic says that you MUST keep your INR betweek 1.5 and 2.0, I urge you to refuse -- or to find another clinic, and certainly - whatever they say - try to get yourself a meter, strips and lancing device and test weekly.

Given your history, I see no reason to take the risk of a repeat TIA, and no significant problems if you keep your INR around 2.5.

 

[Keithl]

I have my On-X for 4 months now. The surgeon said 2-3 for 3 months then 1.5-2 after that with daily low dose aspirin. I met with my cardiologist and we both agree to keep me at 2-3 since even they said the data on 1.5-2 is not convincing and they have heard of strokes with that low of INR with On-X. Either way I was fine, the thought of having to reliably stay within .5-2.0 when I have had .7 swings is stupid. I float between 2.3 and 3.0 with most readings around 2.6 which is right at my personal target.

 

[pellicle]

In my case, I’d prefer to stay above 2.0- just in case. And if there is no harm in that, I don’t understand why they wouldn’t approve it. I suppose I can just dose myself, which may be what I end up doing anyway.

I concur ... if you read the On-X PROACT protocol with care you may find it seems to persuade you to stay above 2 too. https://www.jtcvs.org/article/S0022-5223(14)00010-5/abstract

If you read (fully) that (as the PDF) and pay attention to details you'll see this:

"All patients maintained with warfarin therapy were followed up using weekly home INR testing ... INR Management All patients received a home INR monitor at randomization. The INR control was maintained using weekly home testing, with warfarin dose adjustments made by the clinical sites to minimize INR variability and maximize the time in the INR target range. "​

which suggests that weekly testing is a critical component of this (and you can bet that they had the top shelf INR managers on this not some dumbo at the local clinic).

You may also find this interesting:

"One patient who experienced a minor stroke in the prerandomization period was mistakenly randomized and was immediately withdrawn from the study. "​

 

[Keithl]

I believe the 1.5-2.0 usually comes with low dose aspirin recommendation as well. My experience has been the clinic is a bunch of robots. I work direct with my doctors and my new cardio is fantastic at collaborating with me vs. just telling me what to do. It is your life and health and if they don’t work with you find someone that will. Most doctors, clinics are not used to dealing with informed patients that are actively engaged with their own health care. I seek out doctors that welcome the engagement. My old cardio was one of the best in Atlanta, but I dumped him because his attitude sucked and he could not deal with my active engagement. He was kind of an ass because I went to a level end and got a mechanical valve vs. a tissue valve. He kt questioning me if I understood what I had and what that meant. My new cardio is fantastic.

 

[user 15848]

Hello everyone !

I just hit one year post AvR with my onyx valve. This was my second valve, the first being tissue.

3 months ago I developed a DVT in my upper extremities. My INR at the time of the clot was 2.8 ( per lab draw). My clot was likely due to my pacemaker lead, as the clot formed in that same vein. We actually removed my pacemaker and the leads, since I’ve stopped using it completely. Theoretically I’ve removed the cause of the clot in the first place. We kept my INR between 2.5-3 for a while after the clot.

However, the acc is now trying to keep my INR between 1.5-2.0 per the onyx recommended INR . I questioned them as I had a clot at 2.8 and wondered if I should keep my INR on the higher side, as a precaution. They couldn’t answer the question and basically kept saying “it’s protocol.”

My understanding is that there is no harm in maintaining a higher ( 2.5-3.0) INR , the risk of bleeding is still low correct ?

Do those of you with onyx valves maintain a lower INR ?

Do we as patients have any say in what we want our INR to be, obviously maintaining a safe therapeutic number.

In my case, I’d prefer to stay above 2.0- just in case. And if there is no harm in that, I don’t understand why they wouldn’t approve it. I suppose I can just dose myself, which may be what I end up doing anyway.

Thanks in advance for feedback with this !

Hi, I got an On-X AVR in 2015, and my personal target level for the INR is 2.2, that way if for some reason goes up ( as it does some times) and goes to 3 is fine, and if for some reason goes down to 1.6 i m still within range; the only thing i always keep in mind is to take the 81mg ASA as per On-X;

 

[Protimenow]

I would want to keep it above 2.0 - and not let it slip below 2 for more than a few days. (I have a St. Jude, so I have to keep it above 2.0 - usually 2.5-3.0 or so).

One more thing - if you're testing with the CoaguChek XS, a 1.6 reading may actually be a touch higher than a lab value. I wouldn't let my INR stay that low for very long -- but maintaining your regular dose may be all that's needed to bring it into range (sometimes we do things that will drop the INR, even if we don't realize it; sometimes we do things that increase the INR, again without realizing it. Or sometimes, the INR seems to change on its own. I have to make slight adjustments of my dose every few months, without knowing what made the numbers change).

 

[pellicle]

if you're testing with the CoaguChek XS, a 1.6 reading may actually be a touch higher than a lab value.

or perhaps just simply different:

which is why we shoot for our target INR (which for Aortic Valve is INR=2.5) instead of thinking about boundaries.

 

[vitdoc]

In the real world the drug or equipment rep comes to the doctor's office provides a free lunch to the staff and then the doctor feels obligated to give the rep a few minutes to listen to their pitch.
In the case of the On-X valve the pitch would be to take out a copy of the study suggesting that a lower INR is Ok with that valve. The doctor looks at the study sees the major conclusions and goes away thinking that the valve may have some advantages. Some doctors might actually read the study but most probably don't. They are busy and the headlines will have to suffice.
So if they looked carefully at the study they would see that there was a higher rate of stoke and stroke like events with the lower INR and a higher bleed rate with the higher INR. The study concocted a statistic were they combined the stoke and INR together which showed little difference between the low or high INR groups. So as I mentioned before if your fear is stroke then a higher INR even with the On-X, would based on their study, give you a better chance of avoiding that. If your fear is bleeding then a lower INR would give you an edge. Also these studies take on all comers. So if you carefully monitor your INR you probably would do better than the study. So physicians often get the big picture but not always the fine details.
I would not be surprised if they did the same study with the St. Jude valve they results might be very similar. So for me I keep my INR between 2.5 and 3. I am a stroke adverse person. If I had some sort of bad bleeding issue maybe I would run a bit lower.

 

[Keithl]

I would want to keep it above 2.0 - and not let it slip below 2 for more than a few days. (I have a St. Jude, so I have to keep it above 2.0 - usually 2.5-3.0 or so).

One more thing - if you're testing with the CoaguChek XS, a 1.6 reading may actually be a touch higher than a lab value. I wouldn't let my INR stay that low for very long -- but maintaining your regular dose may be all that's needed to bring it into range (sometimes we do things that will drop the INR, even if we don't realize it; sometimes we do things that increase the INR, again without realizing it. Or sometimes, the INR seems to change on its own. I have to make slight adjustments of my dose every few months, without knowing what made the numbers change).

I have found that at around 2.5 and below my XSand CoagSense PT2 are virtually identical, once the CoagSense reader closer to 3 the XS starts showing .2 or more higher than the CoagSense. I trust the CoagSense fully and more than my XS.

 

[pellicle]

I would not be surprised if they did the same study with the St. Jude valve they results might be very similar.

agreed ... or indeed any of the (virtually identical) bi-leaflet pyrolytic carbon valves on the market.

 

[Protimenow]

I am DEFINITELY stroke adverse. About 7 years ago, I made the mistake of trusting the InRatio with my life. It was easier to use than my ProTime meter, and I didn't have (or see a reason to have) a CoaguChek S or XS.

My INR was fairly stable at 2.6 for quite a while. After I had my TIA (stroke), the hospital result was 1.7. My INR was below 2 for who knows how long?, and I had a stroke. Fortunately, it didnt' cause much damage.

I was committed to finding the most reliable meter, and ran tests with numerous meters - Protime Classic, Protime 3, CoaguChek S, InRatio 1 and InRatio 2 (Alere sent me an InRatio 2 after I told them of my TIA - I probably SHOULD have sued them instead), CoaguChek XS (once I had one) and a few different labs. I also had tests at an anticoagulation clinic that used the Hemoccult meter. I finally got a Coag-Sense to do testing.

According to my many months of testing, I determined that the Coag-Sense is often .2 or so below the lab results (at least, it was for the lab I was using for my tests), and CoaguChek XS was often .1 or .2 higher than the lab. The lab results were often the average of the two meters. I found that the InRatio was often higher than the lab, and at some times MUCH higher than the labs. The CoaguChek XS also, on more than one occasion, was also fairly significantly higher than the labs.

I've seen firsthand how the drug reps (detail people) 'educate' the doctors, and I'm not surprised that some doctors insist that the On-X user is safe with an INR of 1.5 - 2.0. It may take some strokes and deaths of On-X patients with INRs below 2.0 to convince the medical community that INRs below 2 really aren't safe -- even with the On-X valve. It's irresponsible of the detail people to push this valve as better than the others because the patients don't need as high an INR -- the actual impact on people having an INR of 2.5 isn't much different from that for people with 1.5. The 'benefit' argument is a false and dangerous one.

As far as being bleeding adverse - even INRs 4 and above aren't all that dangerous. Still, maintaining an INR of 2.5 plus or minus .5 is really not that big a deal.

 

[Savymom]

Wow this is all such great info! Thank you so much!

I actually missed a call today from the acc clinic director, who left a long voicemail explaining why my INR range is lower. It was all just a bunch of garbage, in my opinion. Although I appreciate him trying to explain it all- he didn’t really provide any logic behind keeping my specific INR lower, especially since I had a clot. Basically stated protocol and the uniqueness of the valve.

Interesting thing. I had been taking 12.5 mg three days and 10 mg the rest, and my INR was maintaining above 2.5. since the clot, I now take 12.5 mg daily and I’m maintaining below 2. Seems odd, maybe not correlated at all, but I don’t know.

I think the bottom line is that I’d like to self manage and talk to my cardio about keeping me above 2.0.

 

[Paul1972]

No need to be going below 2 in my eyes , you gain nothing from keeping it 1.5-2 . Aim for a target of 2-3 All the best Paul xx

 

[Protimenow]

It's best, if possible, to take the same dose daily. This way, no matter which day you self test, you don't have to worry about the dose you took three days earlier giving you a slightly higher (or lower) value. Warfarin is available in many different doses so it's fairly easy to create a daily dose, based on whole pills and half pills.

These clinics are often pretty useless, and the protocols are often stupid.

Having your own meter, supplies, and the drive to self manage is better than trusting misinformed clinics or doctors. Let them tell you the BS that the valve manufacturers sell them on, but take control of your life. An INR above 2 - with a target of 2.5, will reduce your risk of stroke.

 

[pellicle]

I think the bottom line is that I’d like to self manage and talk to my cardio about keeping me above 2.0.

Lots of good folk here to help when you start

Best Wishes

 

[tom in MO]

Wow this is all such great info! Thank you so much!

I actually missed a call today from the acc clinic director, who left a long voicemail explaining why my INR range is lower. It was all just a bunch of garbage, in my opinion. Although I appreciate him trying to explain it all- he didn’t really provide any logic behind keeping my specific INR lower, especially since I had a clot. Basically stated protocol and the uniqueness of the valve.

Interesting thing. I had been taking 12.5 mg three days and 10 mg the rest, and my INR was maintaining above 2.5. since the clot, I now take 12.5 mg daily and I’m maintaining below 2. Seems odd, maybe not correlated at all, but I don’t know.

I think the bottom line is that I’d like to self manage and talk to my cardio about keeping me above 2.0.

Rereading your first post, it appears that the reason for your stroke, the pacemaker lead, is gone, hence they want to manage your INR for your valve which is a range of 1.5-2. The fact they cured the reason for your stroke is a good thing. If it wasn't for your valve, you wouldn't be on warfarin. A lot of patients are on warfarin, then something is fixed, and they get off it.

If your clinic is like mine, it's run by people who specialize in warfarin therapy. So unlike some of the disparaging remarks made here about clinics, the clinic could actually be more "expert" than your cardiologist and probably is more expert in warfarin therapy than your surgeon. For example, with my St. Jude, the hospital and surgeon said 2-3 is the range. However, based upon historical studies, the range was lowered to 2-2.5 immediately after my surgery, thus my clinic recommended 2-2.5. The surgeon indicated that the clinic is the "expert" and to follow their range.

Warfarin therapeutic practices are discussed by cardiologists and presented in papers every few years as a consensus. They are starting points to be tailored to individual situations. This thread has a lot of opinions from people who like to run their INR higher than recommended. Not everyone believes that, especially the majority of the medical profession involved in warfarin therapy for heart valves; the expert opinion is the consensus range.

In contrast, in past years, there has been a contingent of people who wanted to run their INR as low as possible. About 5-7 years ago, everyone wanted the new Onyx valve to take advantage of the low 1.5-2 INR range. People who believed "high is good" said it wasn't possibly to keep your INR stable within a narrow range and it wasn't possible to keep it that low. This has since not been proven true, or the Onyx range would have been widened and elevated.