UC SF. Division of General Internal Medicine UNIVERSITY OF CALIFORNIA SAN FRANCISCO, DIVISION OF HOSPITAL MEDICINE

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Updates in the Management of Venous Thromboembolism Margaret C. Fang, MD, MPH Associate Professor of Medicine UCSF Division of Hospital Medicine Medical Director, Anticoagulation Clinic Venous Thromboembolism (VTE) >350,000 hospitalizations and >100,000 deaths each year in the US Untreated VTE has a high recurrence rate (~50% within 3 months) Anticoagulation is the cornerstone of VTE treatment and prevention UC SF Division of General Internal Medicine UNIVERSITY OF CALIFORNIA SAN FRANCISCO, DIVISION OF HOSPITAL MEDICINE Outline Clinical prediction of PE Predicting mortality after PE Duration of anticoagulation therapy D-dimer and residual venous occlusion Thrombophilia evaluation Newer anticoagulants Case #1 A 67 y/o woman presents to your office with acute right sided chest pain and mild dyspnea. She denies recent immobility or other acute symptoms. Her only medical history is HTN. Exam: BP= 135/70, HR = 88, O2 sat=98% CV: regular, normal S1, S2, no murmurs Lungs: clear bilaterally, normal lung exam Extremities: no edema, erythema, or pain 1

What is this patient s pre-test probability for PE? 1. Low risk (~10%) 2. Intermediate risk (~30%) 3. High risk (~60%) Low risk (~10%... 52% Intermediate r... 41% 7% High risk (~60... Clinical Prediction Rules for Pulmonary Embolism (PE) Various prediction rules are available and seem to have similar accuracy Most extensively validated scores: Wells (and Simplified Wells) Score Depends in part on clinician judgment, and may therefore be subject to bias Geneva Score (and related modifications) Only validated for outpatients Ceriani et al, J Throm Haemost 2010; Kearon et al., 8 th ACCP Guidelines, Chest 2008 Clinical factor Revised Geneva Score Points Age > 65 1 Prior DVT or PE 3 Surgery or fracture within 1 month 2 Active malignancy 2 Heart rate 75-94 3 Heart rate 95 5 Pain with leg palpation + unilateral edema 3 Hemoptysis 2 Low Risk 0 3 (10% PE) Intermediate Risk 4 10 (30% PE) High Risk 11 (65% PE) Clinical factor Wells Criteria Points Clinical Signs of DVT 3 Recent surgery or immobilization 1.5 Heart rate > 100 bpm 1.5 Prior DVT or PE 1.5 Hemoptysis 1 Malignancy 1 Alternative diagnosis less likely than PE 3 Low <2 Mod 2-6 High > 6 (10% PE) (30% PE) (65% PE) OR 4: PE unlikely (12% PE) > 4: PE likely (37% PE) 2

What is this patient s pre-test probability for PE? 1. Low risk (10%) 2. Intermediate risk (30%) 3. High risk (>60%) What would be your next diagnostic step? 1. Obtain chest CT angiogram 2. Obtain a D-dimer blood test 3. Obtain lower extremity ultrasounds Obtain chest C... 16% 4. Do not obtain further work-up for pulmonary embolism Obtain a D-dim... 76% Obtain lower e... 2% 7% Do not obtain... D-Dimer Dimer Testing for PE Quantitative ELISA D-dimer High sensitivity (can rule out ) but poor specificity (cannot rule in because of false positives due to infection, malignancy, older age) Most useful when the probability of PE is low or intermediate Pre-test probability Post-test probability Low (~10%) 0.5 2% Intermediate (~30%) 5 6% High (~65%) 20 35% D-Dimer Dimer for DVT A negative D-dimer also has a high negative predictive value for DVT... IF the patient has a low pre-test probability for DVT May be less useful in patients with cancer or are acutely ill An elevated D-dimer doesn t rule-in DVT it should prompt further testing 3

PE Diagnostic Algorithm 500 ng/ml Suspected PE Wells Score 4 Wells Score > 4 Obtain D-dimer > 500 ng/ml What would be your next diagnostic step? 1. Obtain chest CT angiogram 2. Obtain a D-dimer blood test 3. Obtain lower extremity ultrasounds PE unlikely (0.5%), no further diagnostic tests PE possible (23%), obtain further imaging (e.g., CT) 4. Do not obtain further work-up for pulmonary embolism The Christopher Writing Group, JAMA 2006 Case #2 A 65 y/o man with a history of COPD presents with an unprovoked PE. He is hemodynamically stable. Past medical history is only significant for COPD. Which of the following might help you estimate his short-term term prognosis? 1. Serum troponin 2. Echocardiography 3. History and physical exam 4. BNP 5. All of the above Serum troponin 5% Echocardiograp... 14% History and ph... 23% 0% BNP 59% All of the abo... 4

Predicting Outcomes After PE 3 month mortality rate varies: 1% 17% Factors Associated with Worse PE Outcomes Right ventricular dysfunction Occurs in ~25% of patients with PE Doubles the risk of PE-associated mortality Can identify using Echo, RV measurements on CT, elevated serum BNP Troponin I or T elevation Associated with 3-4x increased risk of 3- month mortality Torbicki, ESC Guidelines, EHJ 2008, Jimenez BJH 2010 Factors Associated with Worse PE Outcomes Note: lack of RV dysfunction and troponin elevation might help you identify patients with good outcomes (high negative predictive value) but poor at predicting patients with bad outcomes Compared to clinical factors, may not provide much additional information on short-term term prognosis Simplified Pulmonary Embolism Severity Index (PESI) Clinical factor Points Age > 80 years 1 History of cancer 1 Chronic cardiopulmonary disease 1 Heart rate 110 bpm 1 Systolic blood pressure < 100 mm Hg 1 Arterial O 2 saturation < 90% 1 0 points: 30 day mortality 1% 1 points: 30 day mortality 9-11% 5

Which of the following might help you estimate his short-term term prognosis? 1. Serum troponin Duration of Anticoagulation 2. Echocardiography 3. History and physical exam 4. BNP 5. All of the above How long would you anticoagulate this patient with PE? 1. 3 months 2. 6 months 3. 12 months 4. Lifelong 11% 64% 9% 16% Depends on Duration of Therapy Risk of VTE recurrence Risk of major bleeding with anticoagulants Patient preference 3 months 6 months 12 months Lifelong Kearon et al, 8 th ACCP Guidelines, Chest 2008 6

Risk Factors for Recurrent VTE Unprovoked VTE High recurrence rate; might be considered a chronic disease process ~10% recurrence at 1 year ~25% recurrence at 5 years ~50% recurrence rate at 10yrs Men with unprovoked VTE ~Twice the risk compared to women VTE in Patients with Cancer Patients with cancer have higher VTE recurrence rates (14% per year) but also higher hemorrhage rates on anticoagulation (10-17%) Low molecular weight heparins (LMWH) appear to be more effective than warfarin in patients with cancer Probably supports using 3 months LMWH for the initial treatment of VTE in cancer Trujillo-Santos et al., Thromb Haemost 2008; Khorana et al, J Clin Oncol 2009. Duration of Therapy Diagnosed VTE Risk Stratification for Unprovoked VTE Unprovoked VTE Female Male No Unprovoked Cancer? Yes Provoked 3 months anticoagulation Count number of risk factors: BMI >30 Age >65 D-dimer on warfarin >250 ng/ml Post-thrombotic syndrome 3 months anticoagulation; Consider indefinite therapy 3 months anticoagulation; then consider further risk stratification Kearon et al, 8 th ACCP Guidelines, Chest 2008 Indefinite anticoagulation 2 Risk of recurrent VTE 10% per yr Consider indefinite anticoagulation Rodger et al, CMAJ 2008 0 1 Risk of recurrent VTE < 3% per yr Consider discontinuation of anticoagulation after 3 months 7

Duration of Therapy Provoked DVT/PE: 3 months Unprovoked DVT/PE: treat for 3 months and consider lifelong therapy Men have a higher risk for recurrence and should consider lifelong therapy Consider further risk stratification in women Decision strongly depends on individualized risks vs. benefits How long would you anticoagulate this patient with PE? 1. 3 months 2. 6 months 3. 12 months 4. Lifelong Risk Stratification for Recurrent VTE D-dimer testing? Residual venous occlusion? Thrombophilia testing? Utility of D-Dimer Dimer Testing to Predict VTE Recurrence after Unprovoked VTE Abnormal D-dimer* after completing 3 months of therapy associated with ~2.2 times increased risk of recurrence Normal D-dimer 3.5% per year Abnormal D-dimer 8.9% per year D-dimers that are initially normal become abnormal 10-15% 15% of the time when rechecked Should probably not be used as the sole test to determine cessation of anticoagulant therapy * Normal D-dimer range varied across studies: generally, < 250-500 ng/ml Verhovsek et al, Ann Intern Med 2008; Cosmi et al, Blood 2010 8

Residual Venous Occlusion (RVO) AESOPUS trial compared fixed-duration duration anticoagulation* to RVO-guided duration Ultrasounds obtained at 3 months, then q6 months If no RVO, anticoagulation was discontinued Assessing for RVO resulted in a mean ~4 5 months additional anticoagulation and lower recurrent VTE rate (11.9% RVO-guided vs. 17.2% in fixed-duration) duration) Substantial rate of RVO at 21 months: 20% 30% RVO may be helpful in identifying patients who benefit from additional anticoagulation after DVT Risk Stratification for Recurrent VTE Serial D-dimer testing and assessing for residual venous occlusion (for DVTs) may have some utility in estimating a person s risk for recurrent events Benefit may come from prolonging course of anticoagulation Still needs to be validated in the setting of clinical prediction rules and outcomes *3 months for provoked VTE, 6 months for unprovoked VTE Prandoni et al, Ann Intern Med 2009 Who of the following would you test for a hereditary thrombophilia? 1. A 55 y/o man who presents with unprovoked PE 2. A 35 y/o woman who presents with unprovoked DVT 3. A 27 y/o asymptomatic woman whose 55 y/o father just developed an unprovoked PE 7% 4. None of the above 5. All of the above A 55 y/o man w... A 35 y/o woman... 20% A 27 y/o asymp... 9% 9% None of the ab... 57% All of the abo... Thrombophilia Testing A number of inherited factors are commonly found in patients with VTE ~20-30% of patients will have 1 factor Only 2.7% will have 2 factors Association is often weak and does not consistently predict recurrence of VTE Only anticardiolipin antibodies or 2 concurrent thrombophilias predict recurrence Kearon et al, 8 th ACCP Guidelines, Chest 2008 9

Thrombophilia Testing Many tests are not accurate in setting of acute VTE and/or anticoagulation therapy E.g., Activated protein C resistance, Protein C, S, and antithrombin functional assays, Factor VIII assay, antiphospholipid antibody testing Factor V Leiden mutation, homocysteine, and Prothrombin gene mutation not affected If testing, should test 2-3 weeks after discontinuation of anticoagulation When to Test? Test if it will change your duration decision Decide on what your management decision will be prior to testing for thrombophilias May affect recommendations for higher-risk risk situations (e.g., extended flights, hormone contraception, pregnancy) If results will change management, consider testing: Young patients with unexplained thromboembolism If there is a strong family history of VTE (first degree relatives who developed idiopathic VTE at age 50 years) VTE that is unusually extensive or in an unusual location (e.g.,., portal vein thrombosis) Dalen JE, Am J Med 2008 Who of the following would you test for a hereditary thrombophilia? 1. A 55 y/o man who presents with unprovoked PE 2. A 35 y/o woman who presents with unprovoked DVT 3. A 27 y/o asymptomatic woman whose 55 y/o father just developed an unprovoked PE 4. None of the above 5. All of the above Newer Anticoagulants Direct thrombin inhibitors (e.g., dabigatran) Factor Xa inhibitors (e.g., rivaroxaban, apixaban) 10

New and Investigational Agents Mechanisms Intrinsic pathway XII XI IX VIII X V II Fibrinogen VII Extrinsic pathway Tissue factor Direct FXa inhibitors (rivaroxaban, apixaban) Direct thrombin inhibitors (dabigatran) Dabigatran for VTE Dabigatran (150mg po bid) compared to adjusted-dose dose warfarin for acute VTE Patients were first treated with parenteral agents and then oral agents for 6 months Because dabigatran is renally excreted, patients with renal insufficiency (creatinine clearance < 30 ml/min) were excluded Fibrin clot Schulman et al., N Engl J Med, 2009 Dabigatran vs. Warfarin: Outcomes at 6 months after VTE Dabigatran (n = 1274) Warfarin (n =1265) Dabigatran vs. Warfarin % patients % patients HR (95%CI) VTE or related 2.4 2.1 death All cause death 1.6 1.7 Major bleeding 1.6 1.9 Any bleeding 16.1 21.9 (major + minor) Schulman et al., N Engl J Med, 2009 1.10 (0.65-1.84) 0.98 (0.53-1.79) 0.82 (0.45-1.48) 0.71 (0.59-0.85) 0.85) Rivaroxaban Rivaroxaban for DVT 15mg po bid for first 3 weeks after initial DVT followed by 20mg once daily Compared to enoxaparin 1 mg/kg bid + vitamin K antagonist (warfarin or acenocoumarol) Standard lengths of treatment (3, 6, or 12 months) The EINSTEIN Investigators, N Engl J Med, 2010 11

Rivaroxaban vs. Enoxaparin-VKA Rivaroxaban (n = 1731) Enox--VKA (n =1718) Rivaroxaban vs. Enox--VKA % patients % patients HR (95%CI) Recurrent VTE 2.1 3.0 All cause death 2.2 2.9 Major bleeding 0.8 1.2 Any bleeding 8.1 8.1 (major + minor) 0.68 (0.44-1.04) 0.67 (0.44-1.02) 0.65 (0.33-1.30) 0.97 (0.76-1.22) Newer Anticoagulants May eventually become alternatives to warfarin Most costly than warfarin Dabigatran nor rivaroxaban have not been approved by the FDA for use in VTE May require additional safety data The EINSTEIN Investigators, N Engl J Med, 2010 Summary Use clinical prediction rules followed by D- dimer testing to help guide further diagnostic testing PE severity index may be useful to identify low risk individuals But does not give clear guidance on duration of hospitalization or optimal management Duration of Therapy Several factors are associated with high recurrence rates of VTE Underlying cancer Unprovoked VTE Men with unprovoked VTE have a high recurrence risk consider lifelong therapy Women may benefit from additional risk stratification 12

Risk Stratification Serial D-dimer testing and ultrasounds for residual venous occlusion might become useful in estimating recurrence risk, but more studies on how to use them are still needed Thrombophilia testing usually recommended only for selected individuals and only if management will change based on the results Newer Anticoagulants Direct thrombin inhibitors and Factor Xa inhibitors may become viable alternatives to warfarin in the future Bibliography Thank you! 1. Ceriani E, Combescure C, Le Gal G, et al.: Clinical prediction rules for pulmonary embolism: a systematic review and meta-analysis. analysis. J Thromb Haemost 2010; 8(5): 957-970. 970. 2. Christiansen SC, Cannegieter SC, Koster T, Vandenbroucke JP, Rosendaal FR: Thrombophilia, clinical factors, and recurrent venous thrombotic events. JAMA 2005; 293(19): 2352-61. 3. Cosmi B, Legnani C, Cini M, Guazzaloca G, Palareti G: D-dimer levels in combination with residual venous obstruction and the risk of recurrence after anticoagulation withdrawal for a first idiopathic deep vein thrombosis. Thromb Haemost 2005; 94(5): 969-74. 4. Cosmi B, Legnani C, Tosetto A, et al.: Usefulness of repeated D-dimer testing after stopping anticoagulation for a first episode of unprovoked venous thromboembolism: the PROLONG II prospective study. Blood 2010; 115(3): 481-488. 488. 5. Dalen JE: Should patients with venous thromboembolism be screened for thrombophilia? Am J Med 2008; 121(6): 458-463. 463. 6. Jimenez D, Aujesky D, Moores L, et al.: Simplification of the Pulmonary Embolism Severity Index for Prognostication in Patients With Acute Symptomatic Pulmonary Embolism. Arch Intern Med 170(15): 1383-1389. 1389. 7. Jimenez D, Yusen RD, Otero R, et al.: Prognostic Models for Selecting Patients With Acute Pulmonary Embolism for Initial Outpatient Therapy. Chest 2007; 132(1): 24-30 8. Kearon C, Kahn SR, Agnelli G, Goldhaber S, Raskob GE, Comerota AJ: Antithrombotic Therapy for Venous Thromboembolic Disease. Chest 2008; 133(6 suppl): 454S-545S. 545S. 13

Bibliography 9. Khorana AA, Streiff MB, Farge D, et al.: Venous Thromboembolism Prophylaxis and Treatment in Cancer: A Consensus Statement of Major Guidelines Panels and Call to Action. J Clin Oncol 2009: JCO.2009.22.3214. 10. Prandoni P, Prins MH, Lensing AW, et al.: Residual thrombosis on ultrasonography to guide the duration of anticoagulation in patients with deep venous thrombosis: a randomized trial. Ann Intern Med 2009; 150(9): 577-585. 585. 11. Rodger MA, Kahn SR, Wells PS, et al.: Identifying unprovoked thromboembolism patients at low risk for recurrence who can discontinue anticoagulant therapy. CMAJ 2008; 179(5): 417-426. 426. 12. Schulman S, Kearon C, Kakkar AK, et al.: Dabigatran versus Warfarin in the Treatment of Acute Venous Thromboembolism. New England Journal of Medicine 2009; 361(24): 2342-2352. 2352. 13. The EINSTEIN Investigators: Oral Rivaroxaban for Symptomatic Venous Thromboembolism. New England Journal of Medicine 2010; 363(26): 2499-2510. 2510. 14. Trujillo-Santos J, Nieto J, Tiberio G, et al.: Predicting recurrences or major bleeding in cancer patients with venous thromboembolism. Findings from the RIETE Registry. Thrombosis and Haemostasis 2008; 100(3): 367-368. 368. 15. Verhovsek M, Douketis JD, Yi Q, et al.: Systematic Review: D-Dimer Dimer to Predict Recurrent Disease after Stopping Anticoagulant Therapy for Unprovoked Venous Thromboembolism. Ann Intern Med 2008; 149(7): 481-490. 490. 16. Writing Group for the Christopher Study I: Effectiveness of Managing Suspected Pulmonary Embolism Using an Algorithm Combining Clinical Probability, D-Dimer Dimer Testing, and Computed Tomography. JAMA: The Journal of the American Medical Association 2006; 295(2): 172-179179 14