10/14/2016

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Atrial Fibrillation UpdateDon’t Miss a Beat

ACEP2016

Corey M. Slovis, M.D.Vanderbilt University Medical Center

Metro Nashville Fire DepartmentNashville International Airport

Nashville, TN

VanderbiltEM.com

Atrial Fibrillation is Common

• # 1 sustained cardiac arrhythmia

• > 3,000,000 patients

• 1% of US population

• 9% of all those ≥ 80 yo

• AFib ED visits 33% in past 5 years

JAMA 2001;285:2370-75

JAMA 2001;285:2370-75

5 Step ED Dx - Rx

• Secure ABCs, with rate control if needed

• Beta Blocker vs Diltiazem

• Determine etiology

• Establish stroke risk (CHA2DS2-VASc)

• Cardiovert, admit or D/C on meds

Pericardium

5 Causes of Atrial Fibrillation

Myocardium

Endocardium

Pulmonary

Hypersympathetic

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There Are 5 Causes of Atrial Fibrillation

• Pericardium

• Myocardium

• Endocardium

• Pulmonary

• Hypersympathetic

Pericarditis

LVH, Myocarditis

Endocarditis, valvulardisease

PE, pulmonary hypertension

Cocaine, amphetamines, hyperthyroid, ETOH withdrawal, caffeine, beta agonists, fever, dehydration

Paroxysmal

5 Types of Atrial Fibrillation

Persistent

Long Standing

Loan AF

Recurrent

There Are 5 Types of Atrial Fibrillation

• Paroxysmal

• Persistent

• Long Standing

• Loan AF

• Recurrent

Terminates spontaneously < 7 days

> 7 days of continued AF

1 year or more

No risk factors and < 60

Repeated episodes often subclinical and not recognized

There Are 5 Routine Tests for All New AF Patients

• CBC

• BMP

• Thyroid

• CXR

• Echocardiogram (sooner or later)

Consider Additional Tests

• BNP

• Troponin

• Exercise Testing

R/O HF

R/O ACS

WPW, Inducible, ACS

Afib = Stroke Risk

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Atrial Fibrillation Equals an Increased Stroke Rate

• About 0.5-1% per year but can be higher

• 5% if no anticoagulation

• CHA2DS2-VASc – important determinant

• Silent cerebral ischemia by CT/MRI is 20-40%

• AF doubles risk of death from age 55 onward (2.2/1.42 F/M)

Always Calculate the Patient’s ScoreCHA2DS2-VASc

• CHF (1)

• Hypertension (1)

• Age ≥ 75 (2)

• Age 65 – 74 (1)

• Diabetes Mellitus (1)

• Stroke/ TIA/Thromboembolic (2)

• Vascular DSX (AMI, PVD, Aortic Plaques (1)

• Sex Female (1)

Chest 2010;137:263-272

0123456789

10111213141516

0

1.3

0 1 2 3 4 5 6 7 8 9

3.2 4.0

Stroke Risk and CHADS2 Score

9.8

6.7

15.2

2.2

6.7

9.6

JAMA 2001;285:2370-75

Alliance for Aging Research: Stroke prevention in AF; 2015

JACC 2016;68:525-68

Stroke Is The Biggest AF Risk

• 5% year if no anticoagulation

• 10% year if prior CVA or TIA

• Anticoagulation decreases CVA risk by at least 2/3

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Rate vs Rhythm Control

• Classic article, 4,060 pts, multicenter

• Average age 70 yo ± 9

• Rate controlled patients had less hospitalizations

• More adverse effects in the rhythm group

• Slightly more deaths too (p = ns; 0.08)

NEJM 2002;347:1825-37

In General: Rate Control is Superior to Rhythm Control

But maybe rate control is not always best for some ED patients

Annals of Emerg Med 2015;65:540-2

• Meta-analysis of 4 ED relevant studies

• 1438 patients with new onset AF

• Rate control if older, chronic AF

• Rhythm > rate control if < 65 yo and healthy

ED Rate vs. Rhythm Control

Younger, healthier patients do better with therapy directed at keeping them

in sinus rhythm

Older, sicker patients do better with their AF rate controlled

Rhythm Control

Rate Control

5 Step ED Dx - Rx

• Secure ABCs, with rate control if needed

• Beta Blocker vs Diltiazem

• Determine etiology

• Establish stroke risk (CHA2DS2-VASc)

• Cardiovert, admit or D/C on meds

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Rate Control in AF• Calcium Channel Blockers

- Diltiazem 25 mg over 1-2 minMay to 35 mg over1-2 min if inadequate response after 5 min

• Beta Blockers- Metoprolol 5 mg IV q 5 min

up to 3 doses

- Esmolol 0.5 mg/kg over 1 min0.05 – 0.1 mg/kg/mintitrate to effect

• Although cardiologists seem to prefer Metoprolol, Diltiazem is as good or better for AF with RVR

• No increased toxicity

• Be careful with dosing

• Older, frailer patients should get less

Rate Control for AF with RVRTake Homes

European Heart 2013;34:1481-88; 1489-97

• The role of Digoxin in Atrial Fibrillation is controversial – it may increase mortality or be a marker for those who will do badly regardless of its use

• In general – don’t be the one to start it

ED Rhythm Control

Cardioversion of Atrial Fibrillation

Safety of ED Cardioversion

• Very safe if no thrombus

• Risk of CVA increases over time

• TEE required if onset unknown or > 48 hrs

• New evidence suggests maybe > 12 hrs

JAMA 2014;312:647-8

0.00.10.20.30.40.50.60.70.80.91.01.11.2

< 12 12-24

0.3%

1.1%

OR=4.0

Risk of CVA S/P Cardioversion without anticoagulants0-48 hrs onset = 0.7% JAMA 2014;312:647-8

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ED Conversion of Atrial Fibrillation

• Medical followed by electrical

• Medication is effective in about 50%-80%

• Electricity is 86%-90% effective

• Not if significant underlying disease(HF, pneumonia, ACS, etc.)

• Must be less than 48 hrs of AFib

Annals Emerg Med 2011;58:517-20

Annals Emerg Med 1999;33:379-87

• 289 stable patients, new onset Afib

• Included patients with AF > 48 hrs (51/289)

• Excluded unstable patients

• Excluded underlying illness requiring admission

• Average age 64 ± 14; HR 125 ± 26

• Used Procainamide (180 pts, 62% of total)

• 500 mg then, if needed, to 1,000 mg

• 50% converted pharmacologically

• 500 mg converted 44%, 56% took 1,000 mg

• Not if prolonged Q-T or Hypotensive

Pharmacological CardioversionAnnals Emerg Med 1999;33:379-87 • This study made ED conversions for

new onset AF a viable practice option

• It is common in Canada and variable in USA

• Many centers do a cardiologist-performed TEE before cardioversion

Am J Emerg Med 2016;34:1486-90

• 236 consecutive Austrian AFib pts

• All with AFib with onset < 48 hrs

• Average age 66.8 ± 11.8; 30 day follow up

•CHA2DS2VASC ≥ 2 in 80%!!

•Mainly used ibutilide, vernakalant and flecainide

How safe and effective is pharmacological cardioversion of Atrial Fibrillation?

• All anticoagulated with LMWH pre-medication

• 72.5% converted with first medication

• Same efficacy for Ibutilide, Vernakalant and Flecainide

• One stroke within 30 days

ResultsAm J Emerg Med 2016;34:1486-90

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• 68 pts with 79.4% effectiveness

• 2.1% toxicity; 1 hypotension, 1bradycardia, 1 AMS

• A new potential non-electrical effective therapy

Vernakalant ResultsAm J Emerg Med 2016;34:1486-90

Electrical Conversion

• AHA recommends 120-200J biphasic

• 50-100J for flutter

• My bias: Use highest recommended

• AP or AL – your choice

• Switch positions if unsuccessful

Cardioversion for Fib/Flutter

Acad Emerg Med 2014; 21:717-26

• Meta-analysis 13 studies

• 836 AP pts vs 856 AL pts

• Trend toward AL > AP if biphasic

Neither A-P nor A-L Pad Placement is Superior

• TEE all others

• If no TEE = 3 weeks pre cardioversion

Anticoagulation Pre Cardioversion

If CHA2DS2-VASc = 0 not needed pre or post

• Transesophageal (TEE) not Transthoracic

• Used to R/O thrombus pre cardioversion

• Mandatory if sx > 48 hrs or unknown

• May be used if > 12 hrs or older pts

• Not required in younger healthy pts if onset is acute and heralded by specific symptoms

Who Needs an Echo in AF

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Annals Emerg Med 2011;58:517-20

“We conclude that it would be within the standard of care to discharge home stable

patients with AFib after cardioversion with adequate follow-up”...“The return rate for

relapsed AFib is 3%-17%”

JACC 2016;68:525-68

• 0

• 1

• 2

• 0

• NOAC or discuss

• NOAC or Warfarin

JAMA 2015; 314:291-2

CHA2DS2-VASc Agent JACC 2015;65:643-4

• Increasing evidence for anticoagulation if CHA2DS2-VASc = 1

• Yearly strokes = 2.75% (m), 2.55% (f)

• Incremental risk if age 65-74

• Do not D/C unless you, patient and cardiologist have all agreed on plan

NOACs now endorsed in ACC/AHA guidelines.

Check carefully for use/dosage in CRF, valvular disease, obese,

fluid and s/p cardioversion

NOACs, DOACsNovel Oral AnticoagulantsDirect Oral Anticoagulants

• Apixaban

• Dabigatran

• Edoxaban

• Rivaroxaban

Eliquis anti-xa

Pradaxa direct antithrombin

Savaysa anti-xa

Xaralto anti-xa

Apixaban

Dabigatran

Edoxaban

Rivaroxaban

Eliquis anti-xa

Pradaxa direct antithrombin

Xaralto anti-xa

Savaysa anti-xa

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BMJ 2016;353:i2868

Is apixaban safer than warfarin in complicated patients on multiple other medications?

• 18,201 Afib pts, apixaban vs warfarin

• Divided pts into ≤ 5 drugs, 6-8, ≥ 9 drugs

• Average age 69

• Converted with 3 mg/kg of vernakalant over 10 min

• More drugs = worse outcomes

Stroke or Systemic Embolism

Major Bleeding NOAC vs WarfarinTake Homes

• 21% less strokes with apixaban(1.27 % per yr vs 1.60%)

• 31% less major bleeding(2.13% per yr vs 3.09%)

• 11% lower mortality(3.52% / yr vs 3.94%)

Older pts with Atrial Fibrillation will have increased morbidity & mortality…but higher

with warfarin than a NOAC

Warfarin use is decreasing and is becoming relegated to mainly those

patients with:

Mechanical Heart Valves

Mitral Stenosis

Chronic Renal FailureLancet 2014;383:955-62

Anticoagulation for AFib• Warfarin:

• Apixaban:

• Edoxiban:

• Dabigatran:

• Rivaroxaban:

INR 2-3; not < 2

5 mg BID2.5 mg BID < 60 kg, > 80 y, Cr > 1.5

60 mg QD > 60 kg30 mg QD > 30 kgNot for pts CrCl > 95

150 mg BID if CrCl > 30

20 mg / d15 mg / d if CrCl 30-49

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• Two populations: CHADS2 ≥ 2 and CHADS2VASC ≥ 2

• 38.2% of 210,380 CHADS2 ≥ 2 got only ASA

• 40.2% of 294,642 Chads2VASC ≥ got only ASA

JACC 2016;67:2913-23

How often do we not follow current recommended anticoagulation guidelines for

high risk Afib patients?

• More than 1 in 3 high risk for stroke AF pts treated below the standard of care!

Anticoagulation and ED Discharge

Annals Emerg Med 2013;62:557-65 Annals Emerg Med 2013;62:566-8

Annals Emerg Med 2015;65:1-12 Annals Emerg Med 2015;66:347-54

• EM MDs need to pay close attention to CHA2DS2-VASc scores

• Anticoagulants started in ED increase compliance and decrease stroke risk

• Don’t discharge patients without considering the need to begin anticoagulation

Should you always provide rate control in borderline sick patients

with Atrial Fibrillation?

Annals of Emerg Med 2015;65:511-22

Is rate control for atrial fibrillation always the best strategy?

• 416 patients with AF

• All patients had “complex” AF

• Complex = an acute underlying illness

• 2 Canadian University affiliated EDs

Annals of Emerg Med 2015;65:511-22

• Shock requiring vasopressors

• Intubation or NIPPV

• Bradycardia requiring pacing or meds

• Stroke or embolic complication

• CPR or death

Major Complications

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0%

10%

20%

30%

40%

50%

Rate or RhythmControl

Attempted

No Rate orRhythm Control

40.7%

7.1%

Major Adverse Complications Annals of Emerg Med 2015;65:511-22

33.6% absolute differenceRR=5.7

0%1%2%3%4%5%6%7%8%9%

10%11%12%13%14%15%

Rate or RhythmControl

Attempted

No Rate orRhythm Control

14.1%

19/135

1.1%

3/281

Total Adverse Events Annals of Emerg Med 2015;65:511-22

13% absolute differenceRR=11.7

0%

10%

20%

30%

40%

50%

ControlAttempted

No Attempt atControl

19.0%

44.5%

Effective Rate Control (> 20 BPM)Annals of Emerg Med 2015;65:511-22

(Elec, D;1+, BB) (Crystalloid, Bronchodilator)

25.5% absolute differenceRR=2.3

Annals of Emerg Med 2015;65:511-22

• 60% (9/15) had cardiovascular complications

• 26.7% (4/15) had medication complications

• 19.0% had pulse reduction of 20 BPM with medical control

• 20% (3/5) had successful electrical conversion

Complication Rate vs. Effectiveness

Trying to Control AF in Sick PatientsTake Homes

• Rarely effective

• Dangerous

• Focus on underlying disease before attempting to control rate or rhythm

In Closing

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AF Rate Control in Complex PatientsTake Homes

• Treat the underlying disease(s)

• It’s dangerous to try to control rate immediately

• Beware underlying sepsis, dehydration, HF

• Beta blockade + HF = ETI

Older pts and higher CHADS2 scores often denote who has an underlying cause of AF with RVR

JACC 2014;64:2246-80

• Definitive recommendations from AHA-ACC

• 201 references, up to 2014

• Every possible table & resource

The Best Single Current Cardiology Reference

Annals of Emerg Med 2015;65:532-9

• Authoritative review

• ED focused

• 48 references including from 2015

The Best Single Current EM Reference

Always Calculate the Patient’s ScoreCHA2DS2-VASc

• CHF (1)

• Hypertension (1)

• Age ≥ 75 (2)

• Age 65 – 74 (1)

• Diabetes Mellitus (1)

• Stroke/ TIA/ Thromboembolic (2)

• Vascular DSX (AMI, PVD, Aortic Plaques (1)

• Sex Female (1)

Chest 2010;137:263-272

5 Step ED Dx - Rx

• Secure ABCs, with rate control if needed

• Beta Blocker vs Diltiazem

• Determine etiology

• Establish stroke risk (CHA2DS2-VASc)

• Cardiovert, admit or D/C on meds

NOACs are here

Become expert in using one

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Atrial Fibrillation is common

Summary

Stroke is high risk

Always calculate CHA2DS2-VASc score

Anticoagulate if indicated

2 = yes, 0 = no, 1 = yes or discuss

Treat underlying conditions

Summary

Dilt or BB for rate control

Cardioversion can be safe < 12-48 hrs

Antiarrhythmics convert 50-80%

200 Joules biphasic works 90%

VanderbiltEM.com