Anticoagulation Therapy: New Opportunities, New Challenges Russell E. Raymond, DO, FACC, FSCAI Interventional Cardiology Cleveland Clinic Foundation Disclosures Russell E. Raymond, DO, FACC, FSCAI Interventional Cardiology Cleveland Clinic Foundation New Kid On The Block Russell E. Raymond, DO, FACC, FSCAI Interventional Cardiology Cleveland Clinic Foundation Indications for Oral Anticoagulation Multiple clinical trials and guideline statements support the use of long-term oral anticoagulation for stroke prevention in high-risk patients with atrial fibrillation (AF).1–8 Long-term oral anticoagulation is also a mainstay in the management of patients with: — Mechanical heart valves — Deep venous thrombosis (DVT) — Pulmonary embolism Developmental History – Current FDA Approved Anticoagulants 1930s Heparin 1950s Warfarin 1970s 1980s 1990s 2002 2010-12 LMWHs DTIs Enoxaparin Dalteparin Tinzaparin Argatroban Bivalirudin Lepirudin Iprivask Factor Xa inhibitor DTI and Factor Xa inhibitors Fondaparinux Dabigatran Rivaroxaban Apixaban Disadvantage of Current Anticoagulants Narrow therapeutic index Need for frequent monitoring Slow onset and offset of action Route of administration Large inter-individual dosing differences Drug-Drug and drug-food interactions Genetic polymorphisms Complications of Current Anticoagulants Bleeding New Thrombosis Heparin-induced thrombocytopenia Warfarin skin necrosis Osteoporosis Warfarin embryopathy Coagulation Cascade Tissue Factor XIIa XIa VIIa IXa Xa Intrinsic Pathway Extrinsic Pathway Factor II (Prothrombin) Fibrinogen Fibrin Clot Vitamin K Sensitive Factors Tissue Factor XIIa XIa VIIa IXa Xa Intrinsic Pathway Extrinsic Pathway Factor II (Prothrombin) Fibrinogen Fibrin Clot © 2013 American College of Chest Physicians Coagulation Cascade Schematic diagram of the coagulation cascade along the tissue factor pathway and the targets of direct factor Xa and thrombin inhibitors. The vitamin K antagonist warfarin typically works on several calciumdependent clotting factors, including factors II, VII, IX (not shown), and X. Warfarin Reduces Stroke Risk in AF by 67% Warfarin Better Control Better AFASAK SPAF BAATAF CAFA SPINAF EAFT Aggregate 100% 50% Hart R et al. Ann Intern Med. 2007;146:857. 0 -50% -100% Optimal INR in AF 15 Odds Ratio Stroke Intracranial Hemorrhage 10 5 1 0 1.0 2.0 3.0 4.0 5.0 6.0 International Normalized Ratio (INR) Fuster et al. J Am Coll Cardiol. 2001;38:1231. Oden et al. Thromb Res. 2006;117:493. 7.0 8.0 CHADS2 Score for Stroke Risk Stratification in AF Annual Risk of Stroke (%) Risk Factor Score 20 18 Congestive Heart Failure (CHF) 1 Hypertension (HT) 1 14 Age > 75 years 1 12 Diabetes 1 Stroke 2 16 8.5 8 5.9 6 2 Gage BF et al. Circulation. 2004;110:2287. 12.5 10 4 0 points .......low risk 1-2 points ....moderate risk > 3 points ... high risk 18.2 4.0 1.9 2.8 0 0 1 2 3 4 Total Score 5 6 Stroke Stroke is 5 times more likely in patients with atrial fibrillation compared with those without. A CVA during atrial fibrillation is twice as likely to cause death and disability compared with non embolic strokes Stroke Risk Stratification in AF CHADS2-VASc Risk Factor Score Annual Risk of Stroke (%) 20 CHF 1 18 HT 1 16 CHADS2-VASc 15.2 14 Age > 75 years 1 Diabetes 1 10 Stroke 2 8 Vascular Disease 1 6 12 9.8 6.7 1 Sex category 1 6.7 4.0 4 Age 65-74 years 3.2 2.2 1.3 2 0 0.0 0 1 2 3 4 5 6 Total Score Lip GY et al. Am J Med. 2010;133:484. Camm J et al. Eur Heart J. 2010;31:2369. 9.6 7 8 9 Stroke Risk Stratification in AF CHADS2 Risk Factor CHF HT Age > 75 years Diabetes Stroke Score 1 1 1 1 2 Annual Risk of Stroke (%) 20 CHADS2 CHADS2-VASc 18 15.2 16 14 12 CHADS2-VASc Risk Factor CHF HT Age > 75 years Diabetes Stroke Vascular Disease Age 65-74 years Sex category 9.8 10 Score 1 1 1 1 2 1 1 1 8 9.6 6.7 6.7 6 4.0 4 3.2 2.2 1.3 2 0.0 0 0 1 2 3 Lip GY et al. Am J Med. 2010;133:484. Camm J et al. Eur Heart J. 2010;31:2369. Miyasaka, et al Circulation 2006; 114:119-125 4 5 6 7 8 9 Bleeding Risk Scores in AF ATRIA HAS-BLED Anemia 3 HT Severe renal disease 3 Age ≥ 75 years HEMORR2HAGES 1 Hepatic or renal disease 1 1 Ethanol abuse 1 2 Stroke 1 Malignancy 1 Any prior hemorrhage 1 Bleeding 1 Older age (> 75 years) 1 HT 1 Labile INR 1 Reduced platelet count or function 1 Elderly (> 65 years) 1 Rebleeding 2 Drug or alcohol use 1 HT 1 Anemia 1 Genetic factors 1 Excessive fall risk 1 Stroke 1 Abnormal renal or liver function Apostolakis S et al. J Am Coll Cardiol. 2012;60:861. Warfarin But... Effective Reversible Inexpensive Slow onset of action Needs regular monitoring Interaction with food Interacts with medications Difficult titration-regular dose adjustments Barriers to Warfarin Use Reasons why physicians don’t use coumadin: — Risk of hemorrhage: 2.0 — Risk of embolus too low: 3.4 — Patient Refusal: 3.6 — Inconvenience of monitoring: 5.2 — Impairs quality of life: 5.2 — Belief that aspirin is superior: 5.2 — Cost: 5.6 — Doubt effectiveness: 6.8 McCrory, et al. Arch Int Med, 1995 The Ideal Oral Anticoagulant Ideally, an oral anticoagulant would: Require no remote monitoring Have little interaction with food or other drugs Offer a good safety profile with regard to bleeding risk Have similar efficacy to warfarin in reducing thromboembolic events Reach therapeutic levels within several hours Oral and/or IV administration Ability to inhibit free and clot bound thrombin Availability of an antidote New Oral Anticoagulants (OACs) Tissue Factor XIIa XIa VIIa IXa Xa Rivaroxaban Apixaban Dabigatran Factor II (Prothrombin) Fibrinogen Fibrin Clot New OACs Characteristic Apixaban Dabigatran Rivaroxaban Direct factor inhibition Xa IIa Xa Bioavailability, % 80 6 80 Peak action, h 1-3 1-3 1-3 Protein binding, % 84 35 92 Renal clearance, % 25 80 33 Elimination T1/2 CrCl > 80 mL/min, h 15.1 13.8 8.3 Elimination T1/2 CrCl < 30 mL/min, h 17.3 27.5 9.5 Novel Oral Anticoagulants (NOACs) Pivotal DB, PC, RCTs vs Warfarin Dabigatran —RE-LY ALL SHOWED Non-inferiority compared with Vitamin K Antagonists (VKA) Better safety Rivaroxaban —ROCKET-AF Apixaban —ARISTOTLE —Reduced ICH Dabigatran (n=18,114) Versus Warfarin in Patients With AF (RE-LY Trial) 4.0 Dabigatran 110 Dabigatran 150 Warfarin 3.5 3.0 * 2.5 2.0 AF ≥1 risk factor 18,000 patients, 951 centers in 44 countries * 1.5 * 1.0 * * 0.5 0.0 CVA/Embolism Major Bleed Connolly S et al. N Engl J Med. 2009;361:1139. ICH MI GI Bleed Rivaroxaban (n=14,264) Versus Warfarin in Nonvalvular AF (ROCKET-AF) 4.0 3.5 14,264 patients with AF and risk of stroke Noninferiority trial Prespecified on-treatment analysis Rivaroxaban Warfarin 3.0 2.5 P < .001 P < .001 2.0 1.5 1.0 P = .02 0.5 0.0 Stroke/Embolism On Stroke/Embolism ITT Treatment Patel MR et al. N Engl J Med. 2011;365:883. Major Bleeding ICH Apixaban (n=18,201) Versus Warfarin in Patients With AF (ARISTOTLE) 4.0 3.5 P = .047 Apixaban Warfarin P < .001 3.0 2.5 2.0 P = .01 1.5 1.0 P < .001 0.5 0.0 CVA/Embolism Major Bleeding Granger CB et al. N Engl J Med. 2011;365:981. ICH Mortality New OACs: Meta-Analysis All Cause Stroke/Systemic Embolism Ischemic and Other Stroke Hemorrhagic Stroke Miller CS et al. Am J Cardiol. 2012;110:453. New OACs: Adverse Events Major Bleeding Intracranial Bleeding Gastrointestinal Bleeding Miller CS et al. Am J Cardiol. 2012;110:453. Dabigatran Associated With Higher Risk of Acute Coronary Events Meta-Analysis of Noninferiority Randomized Controlled Trials Risk of MI or ACS Increased Risk: 33% Absolute Increase 0.4% Mechanism unclear Uchino K et al. Arch Intern Med. 2012;172:397. Dabigatran and Bleeding At present, the FDA is evaluating the post-marketing reports of serious bleeding in patients taking Pradaxa submitted to the Adverse Events Reporting System (AERS) database. While serious, even fatal events have been reported, the FDA is analyzing the events to determine whether the reports of bleeding in patients taking Pradaxa are occurring more commonly than would be expected Dabigatran and Postmarketing Reports of Bleeding “The Mini-Sentinel assessment suggests that bleeding rates associated with dabigatran are not higher than those with warfarin, a finding that is consistent with the results of RE-LY.” Southworth MR et al. N Engl J Med. 2013;368:14. Can the Intensity of Anticoagulation With New OACs Be Measured? Not especially well right now... Coagulation Assays Dabigatran Rivaroxaban Apixaban Prothrombin time Not useful Qualitative Not useful Activated partial thromboplastin time Qualitative Not useful Not useful Thrombin time dTT/HEMOCLOT* Qualitative Quantitative No effect No effect No effect No effect Chromogenic assays Anti-Xa† Anti-IIa No effect Quantitative Quantitative No effect Quantitative No effect *Not currently approved by the US FDA. †Needs to be calibrated for specific drug. Can New OACs Be Reversed? Variable Dabigatran Rivaroxaban Apixaban In vitro No data No data Human volunteers No data No data Hemoperfusion with activated charcoal In vitro No data No data Fresh frozen plasma Mouse model No data No data Activated factor VIIa Rat model Rat and baboon model No data No data No data No data Human volunteers Human volunteers No data Oral activated charcoal Hemodialysis 3-factor prothrombin complex concentrate (PCC) 4-factor PCC Kaatz S et al. Am J Hematol. 2012;(87 suppl 1):S141. Reversal of New OACs: Suggestions Variable Oral activated charcoal Hemodialysis Hemoperfusion with activated charcoal Fresh frozen plasma Activated factor VIIa 3-factor PCC 4-factor PCC Kaatz S et al. Am J Hematol. 2012;(87 suppl 1):S141. Dabigatran Rivaroxaban Apixaban Yes Yes Yes No Yes No Yes Possible Possible No Unclear Unclear Possible No Unclear Unclear Possible No Unclear Unclear Possible Suggested interventions for patients with bleeding due to the new OAC drugs General Measures: Access vital signs and resuscitate appropriately Withdraw the anticoagulant Periodically assess blood count and coagulation cascade Gastric lavage and activated charcoal if within 3 hours of dose Severe Bleeding: ICU and multidisciplinary team care Mechanical compression of accessible sites Surgical intervention if appropriate Hemodialysis (only Dabigatran) Nonspecific prohemostatic agents (Activated prothrombin complex concentrate 50100 U/kg IV (preferred), Recombinant factro VIIa 120 U/kg) Switching to NOAC Coumadin: —INR < 2 start immediately —2<INR<2.5 start the next day —INR > 2.5 wait and recheck INR LMWH —Start at the time of the next dose Unfractionated Heparin: —Start at the time you stop heparin Switching From NOAC To Warfarin — Start both — Monitor INR closely — Discontinue NOAC when INR>= 2 To UFH or LMWH — Start them when it is time for the next pill To another NOAC — Start it when it is time for the next pill Dual Antiplatelet Therapy (DAPT) Instead of OACs In patients who cannot take OACs In addition to OACs DAPT Versus Oral Anticoagulation Clopidogrel plus aspirin versus oral anticoagulation for AF in the Atrial Fibrillation Clopidogrel Trial with Irbesartan for prevention of Vascular Events (ACTIVE W): A randomized controlled trial1 Effect of Clopidogrel Added to Aspirin in Patients with Atrial Fibrillation2 1. ACTIVE Investigators. Lancet. 2006;367:1903. 2. ACTIVE Investigators. N Engl J Med. 2009;360:2066. ACTIVE-W: Clopidogrel Plus Aspirin Versus Oral Anticoagulation in AF 6,706 patients with AF and increased stroke risk ( 1 of: age > 75 years, HT, previous stroke or TIA, EF < 45%, PVD, aged 55-75 versus and DM or CAD) Aspirin 75-100 mg + clopidogrel 75 mg versus warfarin to INR 2.0-3.0 1° EP: composite of stroke, MI, non-CNS embolization, vascular death Primary EP Stroke Major bleeding 2.4% clopidogrel/ASA versus 2.2%/year warfarin; RR = 1.1, P = .57 ACTIVE Investigators. Lancet. 2006;367:1903. ACTIVE-A: Effect of Clopidogrel Added to Aspirin in Patients With AF ACTIVE A: 7,554 patients with AF and increased stroke risk deemed unsuitable for warfarin Aspirin 75 mg + placebo or clopidogrel 75 mg 1° EP: composite of stroke, MI, non-CNS embolization, vascular death Primary EP Stroke Major bleeding 2.0% clopidogrel versus 1.3%/year placebo; RR = 1.57, P < .001 ACTIVE Investigators. N Engl J Med. 2009;360:2066. Triple Therapy (DAPT plus OAC): Trifecta or Triple Threat? Patients with coronary stents require dual antiplatelet therapy (DAPT) with aspirin plus clopidogrel or prasugrel or ticagrelor Patients with AF and coronary artery disease (CAD) can have acute coronary events necessitating stenting Patients with CAD and stents can develop AF DAPT not as effective as oral anticoagulation for stroke prevention in AF Triple Therapy Increases Bleeding Risk 44.4% at 1 year in the WOEST trial, an open-label study in 573 patients on oral anticoagulation undergoing percutaneous coronary intervention (PCI) Most of the oral anticoagulation was with warfarin Little data on the combination of new oral anticoagulations with dual antiplatelet therapy DeWilde WJ et al. Lancet. 2013;381:1107. Strategies for Patients With Stents and AF Avoid drug-eluting stents when you can, especially in patients with a high-bleeding risk — Drug-eluting stents require 6-12 months of DAPT, whereas bare metal stents may only need 1 month Target INR of only 2.0-2.5 May be able to use only one antiplatelet agent In WOEST trial, clopidogrel plus an OAC had both lower bleeding risk (19.4% vs 44.4%) and lower combined event rates compared with triple therapy Putting it All Together: ACCP Guidelines Level of Risk ACCP Alternative* Not Recommended Recommendation Low risk (CHADS2 = 0) No therapy Aspirin Oral anticoagulation or combination therapy with aspirin and clopidogrel Intermediate risk (CHADS2 = 1) Oral anticoagulation Aspirin with clopidogrel Aspirin High risk (CHADS2 = 2) Oral anticoagulation Aspirin with (dabigatran vs clopidogrel warfarin) Aspirin *For patients with AF unsuitable for OACs or those who refuse them. You JJ et al. Chest. 2012;141(2 suppl):e531S. Putting it All Together: Canadian Cardiovascular Society Guidelines Assess thromboembolic risk (CHADS2) CHADS2 = 0 CHADS2 = 1 CHADS2 = 2 OAC Increasing stroke risk No antithrombotic ASA OAC* OAC* No additional risk factors for stroke Either female sex or vascular disease Age >65 years or combination female sex and vascular disease *ASA is a reasonable alternative for some as indicated by risk/benefit Skanes AC et al. Can J Cardiol. 2012;28:125. Newer agents preferred to warfarin Optimal Candidates for Warfarin Patients with renal insufficiency Patients taking stable dose of warfarin and who do not find INR testing burdensome Patients with access to self-testing machines Patients concerned about the lack of an evidencebased reversal strategy Patients concerned about the costs of therapy Optimal Candidates for New OACs Patients who find INR testing burdensome Patients who have trouble staying within target INR range Patients with normal renal function Patients who can afford the medications or can get them Who is a Candidate for the New Anticoagulants? Patients who find it cumbersome to have their warfarin (INR) monitored regularly and/or are not near an anticoagulation clinic Patients unable to achieve and maintain stable International Normalized Ratios (INR) values Patients with a potential for food or drug interactions Putting it All Together Stratify patients with AF by stroke risk Weigh bleeding risk in the balance Choose an evidence-based strategy when you can Match the anticoagulation regimen to the individual patient Thanks for your attention Questions? I would like to acknowledge ACC 2013 and the ACP for material included in this presentation