ANTICOAGULATION IN ATRIAL FIBRILLATION. Heather Kertland St Michael s Hospital University of Toronto

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1 ANTICOAGULATION IN ATRIAL FIBRILLATION Heather Kertland St Michael s Hospital University of Toronto

2 Susan A 73 year old female admitted to the general medicine ward with pneumonia. She had been feeling well, able to do her usual activities (lawn bowling, curling) with no complaints. About 3 days ago became fatigued and developed a cough. Felt feverish and lightheaded. Husband took her to the hospital. An X ray confirmed right lower lobe pneumonia and she was admitted PMH: A fib x 2 years, Hypertension x 8 years, Diabetes x 4 years, Osteoarthritis knees Current medications: ASA 81mg daily Canadasartan/hydrochlorothiazide 16/12.5 po daily Bisoprolol 5 mg daily Heparin 5000 units subcut q12h Metformin 1 g BID Gliclizide MR 30 mg daily Acetaminophen 500 mg Q8H PRN for knee pain (uses 3 days/week) Naproxen 220 mg BID prn for knee pain (uses 1/week) Ceftriaxone 1 g IV 124H Azithromycin 500 mg po q24h Serum Cr 88 umol/l Estimated CrCl 50 ml/min Is Susan on optimal therapy for her atrial fibrillation.

3 New CCS Algorithm

4 CHADS 2 Score Risk Factor Congestive Heart Failure Score Hypertension 1 Age 75 1 Diabetes Mellitus 1 Stroke/TIA/ Thromboembolism Maximum Score Stroke rate/ 100 patient yr % CHADS 2

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6 Susan Susan s cough improved, decreased sputum production. She was discharged home. However, ten days later she returns with complaints of general malaise, some followup labs showed an elevated ALT and AST. Team ordered an abdominal ultrasound which reveals some lesions in her liver. The GI service wanted to biopsy them. What would you recommend to do with her anticoagulation?

7 Perioperative Management of OAC What constitutes low, intermediate and high risk procedures for perioperative bleeding When interruption of OAC is required and when it is not How to stop new direct oral anticoagulants around the time of surgery When to restart OAC after surgery

8 Peri-Procedure/Anticoagulation Management Recommendation We recommend that, in a patient with AF/AFL, a decision to interrupt antithrombotic therapy for an invasive procedure must balance the risks of a thromboembolic event (as indicated by a higher CHADS 2 score, mechanical heart valve, or rheumatic heart disease) with those of a bleeding event (as indicated by a higher HASBLED score and procedures with higher bleeding risk). (Strong Recommendation, Low Quality Evidence)

9 CHEST guidelines Risk Stratum Indications for Oral Anticoagulation Therapy Bridging Mechanical Heart Atrial Fibrillation VTE recommended Valve High Any mitral valve prosthesis Any caged-ball or tilting disc aortic valve prosthesis Recent (within 6 months) stroke or transient ischemic attack CHADS 2 score of 5 or 6 Recent (within 3 months) stroke or transient ischemic attack Rheumatic valvular heart disease Recent (within 3 month) VTE Severe thrombophilia (eg. deficiency of protein C, protein S or antithrombin, antiphospholipid antibodies, or multiple abnormalities) Yes Moderate Bileaflet aortic valve prosthesis and one of the following: atrial fibrillation, prior stroke or transient ischemic attack, hypertension, diabetes, congestive heart failure, age > 75 year CHADS 2 score of 3 or 4 VTE within the past 3 to 12 months Nonsevere thrombophilic conditions (eg. heterozygous factor V Leiden mutation, heterozygous factor II mutation) Recurrent VTE Active cancer (treated within 6 months or palliative) Based on benefit/risk assessment Low Bileaflet aortic valve prosthesis without atrial fibrillation and no other risk factors for stroke CHADS 2 score of 0 to 2 (assuming no prior stroke or transient ischemic attack Single VTE occurred > 12 months ago and no other risk factors No

10 High bleed risk surgery Urologic surgery (TURP, bladder resection, tumor ablation, nephrectomy, kidney biopsy) Colonic polyp resection (> 1 2 cm) Surgery and procedures in highly vascular organs such as kidney, liver and spleen Bowel resection in which bleeding may occur at bowel anastomosis Major surgery with extensive tissue injury (cancer surgery, joint arthroplasty reconstructive plastic surgery) Cardiac, intracranial or spinal surgery especially when small bleeds can have serious consequence

11 Your options are: 1. stop oral anticoagulant; no heparin bridging 2. stop oral anticoagulant; heparin bridging 3. continue warfarin

12 CCPN SPAF card **in liver biopsies hold for a minimum of 4 days

13 St Michael s PAF clinic **in liver biopsies hold for a minimum of 4 days

14 Your options are: 1. stop oral anticoagulant; no heparin bridging 2. stop oral anticoagulant; heparin bridging 3. continue warfarin

15 A guidelines based approach to AF management BRUISE CONTROL: A RCT comparing continued warfarin versus discontinued warfarin with heparin bridging in patients undergoing PPM/ICD surgery. N = 681 significant hematoma other AEs p<0.001 p=ns Birnie DH et al. N Engl J Med 368: , 2013

16 A guidelines based approach to AF management In patients at high risk of thromboembolic events it is customary to use bridging LMWH or UFH heparin during warfarin withdrawal for an invasive procedure. The wisdom of this practice has been questioned by a meta-analysis of 33 observational trials and one RCT reporting that bridging therapy is associated with: an increase in major bleeding (13.1% vs 3.4%, p<0.0001) no reduction in thromboembolic events (0.9% vs 0.6%) Ongoing RCTs PERIOP-2 and BRIDGE Siegel D et al. Circulation 126:1630-9, 2012

17 Bridge trial Age > 18 with chronic (paroxysmal or permanent) afib Warfarin > 3 months, INR 2 3 Elective operation or invasive procedure that required interruption of warfarin therapy At least one CHADS risk factors Randomized to: Stopping warfarin 5 days prior to surgery and restarting 1 2 days post-op Stopping warfarin 5 days prior to surgery and bridging with dalteparin 100 units/kg q12h Douketis JD et al N Engl J Med 2015:373:

18 Bridge trial exclusion criteria Douketis JD et al N Engl J Med 2015:373:

19 Bridge Trial Douketis JD et al N Engl J Med 2015:373:

20 Douketis JD et al N Engl J Med 2015:373:

21 Bridge Trial Douketis JD et al N Engl J Med 2015:373:

22 Recommendation We suggest that interruption of anticoagulant therapy in a patient with AF/AFL is not necessary for most procedures with a very low risk of bleeding (Conditional Recommendation, Low Quality Evidence), including cardiac device implantation (pacemaker or implantable defibrillator) (Conditional Recommendation, High Quality Evidence) Other very low risk of bleeding procedures include most dental procedures, anterior chamber eye surgery, most dermatologic procedures.

23 Peri-Procedure/Anticoagulation Management - Recommendation Recommendation We recommend that interruption of anticoagulant therapy in a patient with AF or AFL will be necessary for most procedures with an intermediate or high risk of major bleeding. (Strong Recommendation, Low Quality Evidence) When a decision to interrupt warfarin therapy for an invasive procedure has been made for a patient with AF/AFL, we suggest that bridging therapy with LMWH or UFH be instituted in a patient at high risk of thromboembolic events (CHADS 2 3, mechanical heart valve, stroke or TIA within 3 months, rheumatic heart disease). (Conditional Recommendation, Low Quality Evidence)

24 Susan her story continues Lesions were benign and ALT/AST return to normal and she feels fine. Eight months later she returns to the emergency department with complaints of GI discomfort, bloating, quickly feeling full when eating. Upon speaking with her, she has been preparing for a walking trip and she has had to use her naproxen in order to complete her preparation hiking. She has been taking two tablets twice daily x 2 weeks. She is diagnosed with NSAID induced ulcer Her hemoglobin is 90, usually it runs 125.

25 Restarting warfarin After GI bleed After intercranial hemorrhage

26 Post-GI bleed Am J Gastroenterol 2015;110:

27 GI bleed Am J Gastroenterol 2015;110:

28 Post-ICH Circulation 2015;132;

29 Post-ICH Circulation 2015;132;

30 Susan Susan s atrial fibrillation is becoming harder to manage. She was switched to a rhythm control strategy to see if this would improve her symptoms. She has tried sotalol (became very fatigued) and amiodarone (severe nausea). She has been sent for a pulmonary vein isolation (ablation) procedure.

31 Contact Force / Cryoablation Technological Advances Improved outcomes Improved sustainability Improved safety

32 AF Ablation lesion set

33 Worldwide AF Ablation ( 03-06) Type of Complication (n=14,218) No of Pts Rate% Femoral pseudoaneurysm AV fistulae Pneumothorax Valve damage/requiring surgery 11/ Tamponade Transient ischaemic attack PV stenosis requiring intervention Stroke Permanent diaphragmatic paralysis Death Atrium-esophageal fistulae TOTAL % Cappato R et al. Circ Arrhythm Electrophysiol. 2010;3:32-8

34 Comparison of North American and European Guidelines CCS Guidelines ESC Guidelines ACCF/AHA/HRS Strength Level of Evidence Class Level of Evidence Class Level of Evidence Paroxysmal* Conditional Moderate IIa (Conditional) A (High) I (Strong) A (High) Persistent* Conditional Moderate IIa (Conditional) B (Moderate) IIa (Conditional) A (High) Failed 1 drug Conditional Moderate I (Strong) A (High) Failed 2 drugs Strong Moderate st Line Conditional Low IIb (Conditional) B (Moderate) PAF / sign. structural heart disease IIb (Conditional) A (High) * Applies to patients with symptomatic AF and failed at least one anti-arrhythmic drug. Dictates ablation performed in experienced centre in patient with minimal heart disease -- Not directly addressed. Often this group is incorporated into other recommendations

35 Ablation Recommendations We recommend catheter ablation of AF in patients who remain symptomatic following adequate trials of anti-arrhythmic drug therapy and in whom a rhythm control strategy remains desired. (Strong Recommendation, Moderate Quality Evidence) We suggest catheter ablation to maintain sinus rhythm as first-line therapy for relief of symptoms in highly selected patients with symptomatic, paroxysmal AF. (Conditional Recommendation, Low Quality Evidence) Values and Preferences: These recommendations recognize that the balance of risk with ablation and benefit in symptom relief and improvement in quality of life must be individualized. They also recognize that patients may have relative or absolute cardiac or non-cardiac contra-indications to specific medications.

36 Peri-ablation anticoagulation High thrombotic risk procedure Vascular complications seen post-procedure Moving target Warfarin (oral anticoagulants) no holding Warfarin/bridge with LMWH ½ dose LMWH post-procedure May be influenced by need to cross atrial septum

37 Long term Doing well 3 months after ablation No recurrent symptoms Loop recorder shows occ. PACs but no AF Susan What would you do? 66 year old man with hypertension (CHADS 2 =1) What would you do? Continue anticoagulation Stop anticoagulation

38 1. Continue OAC 2. Stop dabigatran This is an area of intense debate and there is no correct answer! Studies of long-term monitoring have consistently shown asymptomatic episodes of AF both prior to and following ablation. Symptoms are therefore not a good guide for the presence or absence of AF. It is the standard of practice in many centers internationally to stop the OAC at this stage. However, the need for OAC after a successful ablation has not been rigourously tested in large randomized trials. These trials have been proposed. Obviously, repeat monitoring would be required to document the absence of asymptomatic AF, although documentation of complete elimination of AF may be impossible. At this stage, I would leave this decision to the electrophysiologist involved. He or she may choose to continue the OAC for a period of time in the absence of clear data. Most would agree that if the CHADS-VASc score was 0 (1 in female) OAC should be discontinued. It would not be recommended if AF were present. If the CHADS score was 2 or greater, most would continue the OAC indefinitely. A range of opinions would be expressed for intermediate scores.

39 Practical Tips AF ablation should not be considered as an alternative to oral anticoagulation. If a patient has a high thromboembolic risk profile, then the patient should continue oral anticoagulation even after successful AF ablation. Studies of long-term monitoring have consistently shown asymptomatic episodes of AF both prior to and following ablation Initiation of oral anticoagulation should also not be delayed when indicated in patients pending referral for AF ablation.