May 29, 2023

Venous thromboembolism is common and may recur. Several key case scenarios are discussed and CHEST 2021 Guidelines presented.

Hi everyone i’m rob adaran and in this talk we will discuss in a case-based manner how to treat dbt and pe and for how long we have come a long way since warfarin originally meant to be used as rat poison has been introduced as an anticoagulant we now have a lot of options and we also know that over the course of someone’s life the risk for inherited factors

And their relative contribution tends to diminish whereas the contribution of acquired factors increases there are numerous acquired factors that can increase the risk of venous thromboembolism and a patient may possess more than one in the case of cancer for example the malignancy itself increases the risk the insertion of intravenous ports can play a role as

Can certain agents use to treat the malignancy and there are of course a whole host of other risk factors the challenge when we’re dealing with venous thromboembolism is that of course we’re trying to counterbalance the two devils thrombosis and bleeding with anticoagulation we have the risk of bleeding which can be fatal and with cessation of anticoagulation we

Will have the risk of recurrent venous thromboembolism those advocating ongoing anticoagulation will show you diagrams such as this 10-year follow-up data demonstrating recurrent venous thromboembolism rates which are very high particularly in idiopathic or unprovoked thromboembolism proponents of anticoagulation will also point to synechia that form often after

A dvt these are permanent and these can act as a nidus for recurrent thromboembolism on the other hand bleeding can occur and it can be fatal major bleeding with anticoagulation can be in the order of one to two percent intracranial hemorrhage is possible and if there is a major bleed then the fatality from that can approach 20 and by major bleed the definitions

Include requiring transfusion of at least two units intracranial bleeding retroperitoneal bleeding spinal bleeding and fatal bleeding so to address all these various issues and scenarios the chest guidelines have been released over the years with the most recent one which is what this talk is about being released in 2021 this talk then is not so much about what

I think you should do but rather what the chess guidelines recommend and as with any clinical scenario judgment and the unique aspects of the case have to be taken into consideration so let’s look at the first scenario you have a patient with acute dvt there is iliac vein extension do you administer a anticoagulation b anticoagulation plus catheter directed

Thrombolysis or c systemic lysis and the correct answer in this setting per the chest 2021 guidelines are a anticoagulate only unless there is threatened limb this of course is largely based on the findings of the large attract trial interestingly the british national institute for clinical excellence or nice guidelines from 2020 recommend to perform cdt if

There is low bleed risk the patient has good functional status and there is one year or greater life expectancy the next scenario is in a patient with active cancer who develops venous thromboembolism in this setting do you initiate and maintain with a in oxaparin b warfarin or c doak and the new guidelines recommend douak over lower molecular weight heparins

With a few caveats for instance in luminal gi malignancies low molecular weight heparins or a pigs event might be a better choice and i will explain why in a moment now an important thing that i’d like you to appreciate is that if a patient has active cancer the studies show that the risk of venous thromboembolism or recurrent venous thromboembolism is greater

But so is the risk of major bleeding now the past recommendations to utilize low molecular weight heparin and venous thromboembolism in the setting of cancer came from studies that were done mostly in the early 2000s such as the 2003 clot trial and the 2005 light trial that demonstrated that compared to warfarin low molecular weight heparins led to lower rates of

Recurrent venous thromboembolism without significantly different bleed rates however real-life data shows that patients tend not to like to stay on low molecular weight heparins the self-injection can be problematic and in one study at six months only 37 percent were still utilizing them more recent trials compared doe x to low molecular weight heparins and these

Showed that with dou x you had lower rates of venous thromboembolism particularly rivaroxaban and apixaban however with upper gi and gu cancers there was a greater rate of major bleeding with rivaroxaban and edoxaban so the chest 2021 guidelines recommend that in venous thromboembolism and cancer doax should be utilized over low molecular weight heparins and if

The patient has luminal gi cancer low molecular weight heparins or apixaban would be the preferred agents in the next scenario what anticoagulation duration would you recommend in a patient with unprovoked venous thromboembolism that includes dvt or pe is it a three months b six months or c indefinite and per the chess 2021 guidelines the answer is c indefinite

There have been a number of studies performed over the years that have demonstrated the benefit of extended anticoagulation after unprovoked dvt i would like to show you one the patis dvt study the study took 104 patients who had received warfarin for six months these patients were then randomized to continue warfarin or placebo for a further 18 months now bear

In mind that like many studies where extended anticoagulation is evaluated if the patient had a bleed in the initial treatment phase they would be excluded from the study now what they found at the end of the 18-month extended period is that the group that received warfarin for the extended period had a recurrent venous thromboembolism rate of zero whereas in

The placebo group there was an approximately 30 percent rate of recurrent dvt there were no significant differences in major bleeding the patis dvt trial further followed these patients for 24 months now what’s interesting is that if you look at time zero this is after everyone has completed six months of warfarin the patients have been randomized to further

Warfarin for 18 months or placebo and you can see that in the placebo group the rates of recurrent venous thromboembolism start to rise and they approach around 30 percent at 18 months whereas the warfarin group is a flat line it stays at zero till the 18-month mark now at the 18-month mark the warfarin group also comes off the anticoagulation and the patients

Are followed and you can see that even in that group recurrent venous thromboembolism begins to take effect so much so that by the 42 month mark the group that had received the extended anticoagulation will catch up with the placebo group so this suggests and supports the notion that anticoagulation should be longer term in patients with unprovoked dbt now

The same investigators also completed the patis pe trial in patients with unprovoked pulmonary embolism who either received six months of warfarin anticoagulation and then were randomized to placebo or they were randomized to 18 months of warfarin and you can see that at the 18 month mark as you would expect there are much lower rates of recurrent this is venous

Thromboembolism so dvt and pe in the warfarin group but once the anticoagulation was stopped in the warfarin group also there was a catch-up phenomenon so moving on to the next scenario you have a patient who completes three months of anticoagulant therapy for a dvt that was associated with orthopedic surgery do you now a stop the anticoagulant b continue for

Another three months then reassess or c perform thrombophilia screening then decide the correct answer per chest guidelines is a stop the anticoagulant because the trigger for the dbt the provocative factor is no longer present right moving on to a scenario of pulmonary embolism a 65 year old admitted with acute chest pain and dyspnea cta reveals a left-sided

Pulmonary embolism the patient’s vitals are stable do you a perform catheter lysis b systemic lysis c anticoagulation or d anticoagulation and further tests and in this scenario the correct answer would be d the further tests would include cardiac enzymes as well as an echocardiogram in this scenario the patient remains stable but the serum troponin comes back

Elevated at 2.5 and the echo reveals rv enlargement so do you now continue anticoagulation perform systemic lysis or continue anticoagulation and administer catheter directed therapy and for the chest guidelines the correct answer would be c because this is a patient with intermediate risk pulmonary embolism so you agree to bring the patient to the lab for

Catheter directed thrombolysis but while waiting for the transport the patient’s blood pressure falls and stays at around 80 over 35. do you now a continue cdt as planned b perform systemic lysis or c perform catheter-directed therapy plus systemic lysis the correct answer for chest guidelines is b because the patient now has high-risk pulmonary embolism and

Typically systemic lysis would be appropriate now there are scenarios in pulmonary embolism with shock where catheter directed therapy might be appropriate such as when the patient has high bleed risk or failed lysis or death is likely before the systemic lysis becomes effective and in those settings catheter directed thrombolysis would be reasonable but it is

A weak recommendation right moving on to the scenario of superficial thrombophlebitis do you recommend a warm compress nsaids and follow up do you anticoagulate these patients or does it depend well the chest guidelines with weak recommendations suggest that you should consider anticoagulation if the thrombophlebitis involves the great saphenous vein it’s a

Large area it is extending close to the sapphina femoral junction if the patient has active cancer it is severe or there’s a prior history of dvt or svt as you have seen there are scenarios such as in the setting of unprovoked venous thromboembolism where extending anticoagulation is appropriate but should you administer reduced dose anticoagulation and this

Is in part to reduce bleed risk and the chest 2021 guidelines suggest reduced dose anticoagulation and if done so with rivaroxaban 10 milligrams daily or apixaban 2.5 milligrams twice a day however this is a weak recommendation and the evidence has low certainty here i’m listing for you some very important takeaways from the chest 2021 guidelines one is that the

Venous thromboembolism treatment phase is typically three months this is if it’s a dvt or ape for acute venous thromboembolism the anticoagulant of choice is a douak bear in mind that when it comes to extended anticoagulation while we might be talking forever most of the data so far only goes out to four years if a patient has an isolated distal left leg dvt in

Other words below the popliteal vein then you could consider weekly imaging every two weeks over anticoagulation in the setting of anti-phospholipid syndrome and venous thromboembolism warfarin is preferable therapy this is particularly true in the so-called triple positive patients in the setting of a venous thromboembolism and a transient risk factor do not

Extend anticoagulation and if you have completed anticoagulation and are stopping consider maintaining the patient on aspirin and to summarize the 2021 chess guidelines and wrap up in the setting of provoked venous thromboembolism administer three months of anticoagulation in the setting of unprovoked venous thromboembolism indefinite anticoagulation should be

Administered but do follow bleed risk over time and the setting of venous thromboembolism and active cancer dou x are now recommended over low molecular weight heparins thank you for your attention

Transcribed from video
DVT and PE. Treatment Options. When & What. By Rob Attaran