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ACEP 2017
Atrial Fibrillation Update 2017
Don’t Miss a BeatCorey M. Slovis, M.D.
Vanderbilt University Medical CenterMetro Nashville Fire DepartmentNashville International Airport
Nashville, TN
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
Incidence of Atrial Fibrillation by Age
JAMA Cardiol 2017 Aug; ePub ahead of print
How common is occult Atrial Fibrillation?
• Stroke may be the first manifestation of AFib
• Evaluated high risk for AF pts who were in sinus(CHADS2 ≥ 3)
• Used implantable device in 385 pts
• Followed patients over 30 months
• Evaluated for runs of AFib > 6 minutes
0
10
20
30
40
50
24 mos
6.2
20.4
Incidence of Transient Atrial Fibrillation
30 d 6 mos
JAMA Cardiol 2017 Aug; ePub ahead of print
27.1
12 mos
%
30 mos
33.6
40.0 Atrial Fibrillation is more common than we previously knew in high risk patients
These episodes are unlikely to be picked up if patients only monitored for 30 days
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How many causes of Atrial Fibrillation are there?
There Are 5 Causes of Atrial Fibrillation
• Pericardium
• Myocardium
• Endocardium
• Pulmonary
• Hypersympathetic
Pericarditis
LVH, Myocarditis
Endocarditis, Valvular
PE, pulmonary hypertension
Cocaine, amphetamines, hyperthyroid, ETOH withdrawal, caffeine, beta agonists, fever, dehydration
What are the 5 steps in the treatment of ED patients who
present with either new AFib/Flutter or AFib with RVR?
Secure ABCs
5 Step ED Dx - Rx
Determine etiology
Beta Blocker vs Diltiazem for RVR
Establish stroke risk (CHA2DS2-VASc)
Cardiovert, Admit or D/C on meds
Why is Atrial Fibrillation so dangerous?
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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AFib = Stroke Risk
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
You need to calculate another score:
CHA2DS2-VASc
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 (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
Which is best for patients: Rate or Rhythm Control
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• 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
Annals of Emerg Med 2015;65:540-2
• Meta-analysis of 4 ED relevant studies
• 1,438 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
Secure ABCs
5 Step ED Dx - Rx
Determine etiology
Beta Blocker vs Diltiazem for RVR
Establish stroke risk (CHA2DS2-VASc)
Cardiovert, Admit or D/C on meds
There Are 5 Routine Tests for All New AF Patients
• CBC
• BMP
• Thyroid
• CXR
• Echocardiogram (TEE sooner or later)
Consider Additional Tests
• BNP
• Troponin
• Exercise Testing
R/O HF
R/O ACS
WPW, Inducible, ACS
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A 67 year old woman presents with atrial fibrillation with rapid ventricular
repsonse, HR between 140-160.
She has a history of HF, is very SOB, and sounds wet.
BP is 160/100
Should you always provide rate control in borderline sick patients with Atrial Fibrillation and RVR?
Annals of Emerg Med 2015;65:511-22
Is rate control for atrial fibrillation with RVR 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
0%
10%
20%
30%
40%
50% 40.7%
7.1%
Rate or Rhythm Control
Attempted
Major Adverse Complications Annals of Emerg Med 2015;65:511-22
33.6% absolute differenceRR=5.7
82% relative decrease
No rate or Rhythm Control
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0%
10%
20%
30%
40%
50%
19.0%
44.5%
Effective Rate Control (> 20 BPM)Annals of Emerg Med 2015;65:511-22
Control Attempted(Elec, Dilt, BB)
No Attempt at Control(Crystalloid, Bronchodilator)
25.5% absolute differenceRR=2.3
Electrical cardioversion was only effective in 13.3 % of
these sick patients
AF Rate or Rhythm Control in Sick Patients
Take Homes
• Rarely effective
• Dangerous
• Focus on underlying disease before attempting to control rate or rhythm
Be aggressive with fluids, oxygenation, correcting electrolyte abnormalities before using antiarrhythmics
Beta blockers first line if spontaneous conversion does not occur
Mortality from 26.1% to 61.3% if pts stay in AFib
Crit Care Med 2016;20:373-82
Study is not about acute AFib in ED septic patients….do not try to convert septic pts in ED
A patient presents with likely PSVT –is 6 mg or 12 mg adenosine better ?
Adenosine can kill patients with bypass tracks if: Wide and Irregular
Adenosine increases rapid bypass tract conduction and can result in very fast
refractory VFib
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Wide complex Afib and Adenosine =
A rapid Vfib death
Don’t Use Adenosine
• Never give if wide and irregular
• Never give if rate < 150
• Never if only slows during vagal stim
• Careful if hx of AFib, Aflutter, MAT
• Careful if hx of CHF, COPD, WPW
Rate Control in Stable PatientsAFib/AFlutter
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Rate Control in AF with RVR• 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
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 poorly regardless of its use
• In general – don’t be the one to start it
A 47 year old man presents with new onset atrial fibrillation.
He has well controlled hypertension and no history of AFib.
He felt his heart start to beat “funny” a few hours ago after running?
Can you safely convert rate stable Atrial
Fibrillation and Flutter?
Safety of ED Cardioversion
• Safe if AF is acute
• 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
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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
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 admission-requiring illnesses
• 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
• 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
• 1,091 pts, mean age 63.9 years, 2010-2012
• 6 academic centers, 84.7% AFib, 15.3%Aflutter
• Clear history of onset ≤ 48 hrs
• Clear 7d history and no thrombus by TEE
Ann Emerg Med 2017;69:562-71
Is Canadian “aggressive care” with cardioversion effective and safe?
• Study excludes patients with other primary diagnoses or complaints including:
- ACS- CHF- Pneumonia- PE- Sepsis and/or SIRS criteria
Ann Emerg Med 2017;69:562-71
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Rapid ED CardioversionInitial Therapy
• Rhythm control in 72.8%
- 39.1% electrocardioversion first
- 33.7% rhythm converting drug first
• Just rate control in 17.8%
- Metoprolol 65.1%
- Diltiazem 32.2%
Ann Emerg Med 2017;69:562-71
PharmacologicRhythm Control
• Procainamide used in 85%
• Converted 52.2% of patients
• Use 35-50 mg/min (up to 20 mg/kg)
• Can go faster - but careful!
Synchronized Cardioversion Effectiveness
• 90.0% successful electrical conversion
- Mean max energy 148 joules
- 1.4 mean shocks required
Ann Emerg Med 2017;69:562-71
Electrical Conversion
• AHA recommends 120-200J biphasic
• 50-100J for flutter
• My bias: Use highest recommended: 200 or more
• 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
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• 80.1% conversion to sinus rhythm
• 1 stroke and no deaths at 30 days(89 yo F on coumadin who had spontaneously converted in ED)
Ann Emerg Med 2017;69:562-71
Is Canadian “aggressive care” with cardioversion effective and safe?
Do patients you see in new AFib need to be
anticoagulated…?How about if you can
convert them?
• 0
• 1
• 2
• 0
• NOAC or discuss
• NOAC or Warfarin
JAMA 2015; 314:291-2
CHA2DS2-VASc AgentNon-vitamin K anticoagulants now endorsed in ACC/AHA guidelines.
Check carefully for use/dosage in CRF, valvular disease, obese, and
s/p cardioversion
Non-Vitamin K AnticoagulantsNovel 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• 76,354 pts
• Compared each non-vit K drug to Warfarin
• Apixaban lowered stroke risk 33% vs Warfarin
• Apixaban and dabigatran lowered GI bleed risk
• All decreased risk of intracranial bleeding
J Am Heart Assoc 2016;5:e003725
Are the non-vitamin K oral anticoagulants safer than Warfarin?
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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 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
If you don’t discharge a patient on a non-vitamin K antagonist when
indicated, it can take weeks-months for it to be started…and allow a
preventable stroke to occur• Two populations: CHADS2 ≥ 2 and CHA2DS2VASc ≥ 2
• 38.2% of 210,380 CHADS2 ≥ 2 got only ASA
• 40.2% of 294,642 CHA2DS2VASc ≥ 2 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!
Non-vitamin K oral anticoagulants are here
Become expert in using one• 5,738 pts from the ORBIT-AF II Registry
• Routine lab evaluation not required with NOACs
• Considered safer than Warfarin
• Some patients require dosing modifications
JACC 2016;68:2597-604
Are we dosing non-vitamin K antagonists correctly?
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• 87% being dosed correctly
• 9.4% underdosed
• 3.4% overdosed
• Renal disease was # 1 cause of dosing errors
• More strokes, bleeds, AMIs & hospitalizations
Results JACC 2016;68:2597-604
Take HomesNon Vitamin K Oral Anticoagulants
NOACs
• 1 in 8 AF patients are dosed incorrectly
• Under and over dosing increases morbidity and mortality
• Do not discharge patients with renal impairment on a NOAC without working with an ED or hospital pharmacist and/or an AFib focused cardiologist
Summary
Secure ABCs
5 Step ED Dx - Rx
Determine etiology
Beta Blocker vs Diltiazem for RVR
Establish stroke risk (CHA2DS2-VASc)
Cardiovert, Admit or D/C on meds
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 half
200 Joules biphasic works 90%
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