Clot Be Gone

February 4, 2008 11:38 AM

I've been diagnosed with deep vein thrombosis (DVT) -- a blood clot -- and I have questions about current best practices for treatment...

Doppler ultrasound has shown a clot that begins in my calf and continues behind my knee and half way up my thigh. I've mostly gotten over the freaking-out part, and am focused on optimizing my chance for complete recovery. I'm 41, and have lots of living still to do.

I'm currently undergoing "the usual" treatment... twice-daily injections of heparin and increasing doses of warfarin with the target of getting my blood's INR to the range of 2.0 to 2.5. I'm nearly there, and the heparin will end soon as I reach the INR, and warfarin will continue for a minimum of 6 months. Since the actual cause of the blood clot itself is an unknown, we're also doing various screening panels to see if there may be other disease factors that may have resulted in DVT.

I'm reading various medical reports of a relatively new treatment called "rapid lysis" which uses a spray of clot-dissolving stuff and a vacuum nozzle -- both delivered via catheter -- to quickly eliminate or reduce the clot, resulting in fairly immediate relief from pain, and more important, from risk of pulmonary embolism and long-term effects of PST (post-thrombotic syndrome) which can result in damaged valves in veins, scarring and the like. Is this more widely in use than my doctor seems to believe?

Finally, I find it curious -- and a bit maddening -- that on completion of the current course of treatment my doctor doesn't plan a follow-up scan (ultrasound or otherwise) to see that the clot has been suitably reduced, subsumed, etc. but instead intends to trust that the treatment has done as intended. Me, I'm a believer in "trust, but verify".

I'm asking all the same questions of my doctor (I'm a fairly assertive patient, I guess) and hope to augment my understanding with that of the hive mind.

Thanks!

posted by anonymous to health & fitness (14 answers total)

Has your doctor provided you with any explanation for his unwillingess to do a followup scan other than "nope, we're not going to do it?" Don't be afraid to ask questions.

One possible explanation: is your insurance or national health-care system willing to pay for a follow-up scan? That could be what's driving your doctor's decision.
posted by deadmessenger at 12:32 PM on February 4, 2008

Long time ingester of sodium wafarin (Coumadin) here. Not a doctor. This is based on my own personal experience...

Recovery from your specific DVT is more or less a certainty so don't let it get in the way of living. I had my first incident 17 years ago discovered only because I was hacking up congealed blood. Definitely do the panels and screenings but don't get too enthused about finding a problem unless there is a family history or you've undergone some obvious physical trama. I've had four instances of unexplained DVT since the first and after three inconclusive rounds of tests they've decided I'm just going to be eating wafarin for the remainder of my days as a precaution. If they do find the cause, then it's likely you'll be eating wafarin for the remainder of your days, but at least you'll know why.

If they find nothing, you'll likely be removed from wafarin after six - eight months and that's all you'll ever know. The six - eight months is already a safe bet given your body will reabsorb the clot in the first couple of months or so. It's just cheaper to monitor your INR and feed you wafarin than to schedule and conduct an ultrasound.

If you are experiencing full-on pain instead of a vague discomfort, you should definitely pursue some of the more recent treatment modalities. If the pain is bearable, your doctor is likely to forgo the invasive treatments because the cost to benefit ratio isn't that great. Dropping in via catheter brings along its own risk of shifting the clot and bringing on some serious emboli.

All things considered, doing rat poison (sodium wafarin == the active ingredient in Decon which is a fun bit of trivia) is pretty easy on the list of chronic problems. The only big drawbacks are having to refrain from participating in high energy contact sports, not being able to pound Excedrin (or anything but 1 regular strength tylenol) for any pain/headache, and moderating your alcohol intake.

Like I said, been doing this for well-near a decade and still going strong. If you've got any other questions or want to chat there's always Mefi Mail...
posted by Fezboy! at 12:39 PM on February 4, 2008 [2 favorites]

Not a doctor or a clotter...

My mom had a clot in arm which was related to a PIIC line she needed temporarily. I know she was scanned after the course of blood thinners. That may have been because her family doctor botched her initial diagnosis. The specialists were all being extra careful so we didn't sue for malpractice. (We didn't. Thankfully, my mom recovered.) I had a strong sense that my mother was on some special "don't eff this up any more than her family doctor already did" doctor's protocol.

Instead of asking your doctor, why don't you get a second opinion. It doesn't sound as though you have a lot of trust in your physician.
posted by 26.2 at 1:28 PM on February 4, 2008

FYI You are not alone. It seems absurd that the doc won't do a 2nd scan. That's like pissing on an inferno and trusting that the fire is out.
posted by Gungho at 1:58 PM on February 4, 2008

Sorry - I bumblefingered that. It was a PICC line. Carry on.
posted by 26.2 at 2:34 PM on February 4, 2008

I had two DVTs in two separate countries before hitting twenty-five. None of the umpty-tumpty doctors I saw did a second scan. It's easy to get really freaked out by getting a DVT and to stay that way for a long time, particularly when you're young and there's no real explanation of why you had the DVT. (It does lead to one of my favorite My-Medical-Emergency-In-The-Republic-of-Georgia stories, though, which involved a showdown between my irate host mother and the world's craziest gynecologist.) Doctors in particular, in my experience and that of my friends, tend to take DVTs a lot more casually than the patients do, which is infuriating when you have a giant blood clot, which could kill you (it won't now that it's diagnosed, but you're probably not thinking like that-- God knows I wasn't, even with my second), in your leg and the doctor is just like "here, inject yourself with some heparin and shut up." With my first DVT, which was much worse than the second, I was prescribed compression stockings to avoid post-phlebitic symptoms; I wore them off and on for the next year or so. This seems to have been mostly successful.

My understanding is that surgery is reserved for particularly dangerous cases or those where the thrombosis is particularly deep. It was never suggested to me or any of my friends who have had DVTs, although my doctors in Georgia did seem under the impression that it was more common in the US than in Georgia. (This was in the context of "We care about you more than those US doctors ever could and are taking much better care of you than they would!" so I would take it with a grain of salt. Ironically, their opinion later proved correct.) If you're still in serious pain, talk to your doctor. In Georgia I got periodic injections of God only knows what when the pain was really awful, and in the US they handed me a bottle of vicodin "for if you really need it," despite the heparin- and warfarin-induced restrictions on pain medication. After treatment progressed the pain was definitely more bearable. I think the compression stockings helped.
posted by posadnitsa at 3:53 PM on February 4, 2008 [1 favorite]

I'm told that clot-busting agents are risky. If your clot dissolved nicely, that'd be great. If your clot broke up in an irregular way and a large portion floated off you could get a PE and be dead in 60 seconds. If you go into the vein from above you could of course but in an IVC screen/suction. That's also kind of a pain since you're anti-coagulated and would bleed profusely from wherever they stuck you.
posted by a robot made out of meat at 5:43 PM on February 4, 2008

Standard therapy is the heparin or warfarin. Sometimes people will have an IVC filter placed (see indications), but lysis of a clot is invasive and my general understanding from the interventional radiologists or surgeons generally requires the patient to have a life-threatening pulmonary embolism. The lysis would get rid of the current clot, but the reason you're kept on warfarin for 6 months is to keep your blood thin so you don't start developing any NEW clots (ones that might be unstable and dislodge and go to your lungs and kill you).

(This is education, not medical advice. You are not my patient, I am not your doctor, I am not a doctor.)
posted by gramcracker at 6:27 PM on February 4, 2008 [1 favorite]

You are right to want to verify that the treatment worked when you are dealing with a condition that's in the "potentially life-threatening" category.

(Are you carrying a card or medical alert type of thing so that in case something happens they know you are on Heparin and rat poison and suffering from DVT? I would, just in case.)

Good luck!
posted by gjc at 6:40 PM on February 4, 2008

So let me answer the easier question first and the harder question second.

Rapid lysis for deep vein thrombosis is definitely not considered a standard of care type procedure and is not practiced commonly for routine DVT. The best indication for lysis therapy is something know as phlegmasia cerulea dolens which basically refers to DVTs with such an extreme clot burden that there is intractable leg swelling, possible compromise of the blood supply to the leg, and major loss of function. These aren't the case in the vast majority of DVTs. There is some soft data to suggest that thrombolysis does in fact reduce the risk of postphlebitic syndrome, but in most experts' opinions, this potential benefit is far outweighed by the risk of major bleeding. Some estimates of "major bleeding" after thrombolytics are in the neighborhood of 20% with maybe 3% risk of a catastrophic intracranial hemorrhage. This is why thrombolysis is generally considered a no-no outside of severe cases of DVT or pulmonary embolism. Even in the case of the latter, thrombolysis is reserved in most cases for patients who are at high risk for obstructive shock and death.

Now to the harder issue... There is considerable variation on how DVTs are managed long term. A 6 month course of anticoagulation is pretty standard. What happens after that is up for more debate. Studies (see the PREVENT and ELATE trials if you want too much info) suggest that the risk of recurrent thromboembolic disease after 6 months is on the order of about 8 episodes per 100-patient-years if therapy is stopped whereas the rate is 1 or fewer episodes per 100-patient-years for continued therapy at a goal INR of 2-3. Though it hasn't become widespread practice yet at least in primary care clinics, there is considerably good data that shows that patients who have ultrasonographic evidence of residual clot or elevated serum D-dimer levels at the end of a 6 month course of therapy can predict a higher risk of recurrence. We do still need more data, but either of the above may make you 2-3 times more likely to have recurrence.

The things is, you're basically faced with two options at that point: continued treatment for an undetermined period of time or discontinuation. Some doctors simply abhor the idea of indefinite anticoagulation unless there is a damn good reason for it, so some of the data I mentioned above hasn't completely sunk in with people in practice. My personal feeling, especially with a patient as astute and thoughtful as yourself, is that competent patient's can be told the statistical risks and options available and make an educated decision based on these risks. Some may say they hate coumadin and want to be off of it regardless. Others are paranoid/concerned enough to want to stay on indefinitely. Still others might actually want things like D-dimer testing or follow-up ultrasound to help make the decision of how long if at all to continue therapy with anticoagulation. Now ask yourself if you are the type of person who falls into one of the first two categories. If so, forget the ultrasound and other tests as it won't change a thing. But if you fall into the third group, definitely let it be known to your doctor. And if they aren't receptive to working with you to make a decision that respects your autonomy, then find another doctor.
posted by drpynchon at 7:51 PM on February 4, 2008 [3 favorites]

The answers posted here have been every bit as thoughtful, helpful and authoritative as I could have hoped for... and so I feel compelled to "out" myself as the anonymous poster to thank y'all.

By way of follow-up, apparently my body laughs in the face of warfarin (my latest INR is *down* from 1.9 to 1.5) so I'm continuing heparin for the next several days while upping my daily warfarin dose to 9mg. I meet again with my doc in a couple days.

Is it possible that INR numbers not quite so "normalized" as they're made out to be?
posted by deCadmus at 8:50 PM on February 4, 2008

Extra servings of leafy green veggies the night before? It is also important to be consistent about the time you take your meds and the time of day you are tested to get an accurate reading. I always get tested in the mornings and take my meds with dinner.
posted by Fezboy! at 3:22 AM on February 5, 2008

Warfarin interacts with pretty much every drug (not literally true) and lots of herbals. One particularly aggravating episode had a guy taking ginseng for months and denying it up and down. Since it's a vitamin k antagonist, if you eat an especially vit k rich meal, it will not work as well.
posted by a robot made out of meat at 8:16 AM on February 5, 2008

Unless you eat the exact same thing every day you are going to see some whacked out INRs. I you are going to be on coumadin for a long time or have high co-pays for blood work, you might want to consider getting your own testing machine. You can get one for about $1500.
posted by ryanissuper at 3:00 PM on February 5, 2008