Stroke Prophylaxis in AFib. Anil K. Gehi, MD Associate Professor of Medicine

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1 Stroke Prophylaxis in AFib Anil K. Gehi, MD Associate Professor of Medicine

2 Case #1 72 year-old woman with high blood pressure, osteoporosis, pacemaker Noted on routine pacemaker check to have atrial fibrillation Most episodes about 10 minutes, some up to 10 hours patient unaware Takes aspirin No history of bleeding

3 Case #2 46 year-old woman with diabetes Urgent care visit for heart fluttering Found to have atrial fibrillation on EKG Episode resolved on its own within 24 hours Recalls similar episode last year lasting 2-3 hours

4 Case #3 61 year-old man Noted by primary care provider to have irregular heart rhythm Atrial fibrillation on EKG Unclear how long has been going on Patient notes increased fatigue, less energy over last few months

5 Case #4 83 year-old man with congestive heart failure, atrial fibrillation Takes apixaban (eliquis) to prevent stroke Presented to ER with weakness, low blood pressure Hospitalized for anemia, found to have bleeding ulcer Required blood transfusion

6 Five million Americans with AF by 2040 Go et al. JAMA. 2001;285:

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8 Four pillars of AF management AF prevention hypertension, heart failure, sleep apnea, obesity, etc Stroke prevention Rate control Rhythm control

9 Relative risk of stroke and mortality with AF

10 Stroke in AFib

11 Left atrial appendage blood clot (thrombus)

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13 Signs of stroke

14 Risk for stroke

15 Risk for stroke: CHA 2 DS 2 -VASc score

16 Why do AFib patients gets clots? Not so simple as stagnant blood in appendage during AFib Watson T, et al. Lancet

17 Risk not clearly dependent on AF duration

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19 Thin the blood to prevent clots

20 Occlude the left atrial appendage to prevent clots Endocardial Epicardial

21 Dr. Karl Paul Link Chemist, University of Wisconsin 1920: Outbreak of cattle deaths in Wisconsin and Canada 1941: Isolated dicumarol from coumarin molecules in the sweet clover Wisconsin Alumni Research Foundation

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23 Dr. Karl Paul Link Recognized possible medical use Started being used in humans in 1954 Early recipient: 1955 (heart attack)

24 What s wrong with warfarin? Slow onset of action Slow offset of action Multiple drug / dietary interactions Monitoring required to maintain therapeutic range Narrow therapeutic range Labor intensive for patient / health care provider / system Under-use due to fear of adverse events and complexity of management

25 What s wrong with warfarin? Only INR> 2.0 confers protection Stroke /100 pt years ICH 0 < >4.5 Hylek et al NEJM 2003;349:

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27 New developments

28 Dabigatran (2010)

29 Rivaroxaban (2011)

30 Apixaban (2012)

31 Edoxaban (2015)

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39 Advantages of new drugs over warfarin Rapid onset / offset Predictable effect with fixed dosing (no monitoring) Limited food / drug interactions Safer Possible superior efficacy

40 Current AF Guidelines Risk Profile Recommended Therapy No risk factors CHA 2 DS 2 -VASc=0 CHA 2 DS 2 -VASc=1 European guidelines Nothing NOAC>VKA US guidelines Nothing Nothing or ASA or OAC CHA 2 DS 2 -VASc >2 NOAC>VKA NOAC or VKA Mechanical Valve Warfarin: INR for aortic Warfarin: INR for mitral VKA=vitamin K antagonist ESC Guidelines: Eur Heart J. 2012; AHA/ACC/HRS Guidelines. J Am Coll Cardiol

41 Disadvantages of new drugs over warfarin No routine monitoring Cannot titrate dose Can t measure drug activity if needed Short half-life Effect declines quickly if adherence poor Poor compliance may affect efficacy more than with warfarin No fast-acting antidote* Can t use if mechanical valves Limited data in those with kidney dysfunction Cost

42 Antidotes approved! Idarucizumab (Praxbind ) FDA approval October, 2015 Target: Dabigatran Structure: Humanized antibody fragment (FAb) to dabigatran Andexanet alpha FDA approved May, 2018 Target: Rivaroxaban, Apixaban, Edoxaban Structure: FXa lacking catalytic and binding activity

43 What about patients with bleeding problems?

44 Signs, symptoms of possible internal bleeding Pale skin *Rectal bleeding bright red or black / tarry Vomiting blood bright red or dark brown coffee grounds Tender, swollen, bruised, or hard areas with bruising underneath the skin Blood stained urine Vaginal bleeding Coughing blood Headache with confusion, drowsy, faint Rapid, weak pulse

45 Risk for bleeding HAS-BLED score

46 AVERROES Study terminated early by DSMB

47 Stop other unnecessary blood thinners

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49 Endocardial (WATCHMAN)

50 Left atrial appendage occlusion

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52 Procedural success

53 Procedural safety 12% 10% 9.9% 8% Patients With Safety Event (%) 6% 4% 4.8% 4.1% 4.1% 3.8% 2.8% 2% 0% PROTECT AF 1st Half PROTECT AF 2nd Half CAP PREVAIL CAP2 EWOLUTION*

54 Bottom line Preventing strokes is critical AFib patients are at risk for clots in the left atrial appendage Use CHA 2 D 2 -VaSC to determine your risk Non-warfarin blood thinners are preferred if possible Patients who cannot take blood thinners should be considered for appendage occlusion Watch for bleeding, watch for stroke DOING SOMETHING IS MUCH BETTER THAN DOING NOTHING

55 Case #1 72 year-old woman with high blood pressure, osteoporosis, pacemaker Noted on routine pacemaker check to have atrial fibrillation Most episodes about 10 minutes, some up to 10 hours patient unaware Takes aspirin No history of bleeding

56 Case #1 CHA 2 D 2 -VaSC: 3 Rec: stop aspirin, take anticoagulant Chose apixaban

57 Case #2 46 year-old woman with diabetes Urgent care visit for heart fluttering Found to have atrial fibrillation on EKG Episode resolved on its own within 24 hours Recalls similar episode last year lasting 2-3 hours

58 Case #2 CHA 2 D 2 -VaSC: 2 Rec: take anticoagulant Chose dabigatran

59 Case #3 61 year-old man Noted by primary care provider to have irregular heart rhythm Atrial fibrillation on EKG Unclear how long has been going on Patient notes increased fatigue, less energy over last few months

60 Case #3 CHA 2 D 2 -VaSC: 0 Rec: no therapy

61 Case #4 83 year-old man with congestive heart failure, atrial fibrillation Takes apixaban (eliquis) to prevent stroke Presented to ER with weakness, low blood pressure Hospitalized for anemia, found to have bleeding ulcer Required blood transfusion

62 Case #4 CHA 2 D 2 -VaSC: 3 Episode of major bleeding (not reversible) Rec: left atrial appendage occlusion

63 QUESTIONS?