atrila fibrillation

1. ATRIAL FIBRILLATION
MANAGEMENT
Ralph GHORAYEB

2. 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial
Fibrillation
http://www.uptodate.com/contents/management-of-new-onset-atrial-
fibrillation
http://www.uptodate.com/contents/atrial-fibrillation-cardioversion-to-sinus-
rhythm
Ferri's Clinical Advisor 2015

3. EKG

4. CLASSIFICATION
Multiple classification schemes have been used in the past to
characterize AF. The current classification scheme (divided into three
major types) used by the ACC/AHA guideline committee is as follows:
Paroxysmal AF—more than one episode of AF that terminate
spontaneously within 7 days (most episodes last less than 24 hr)
Persistent AF—episodes of AF that last longer than 7 days and may
require either pharmacologic or electrical intervention to terminate
Permanent AF—AF that has persisted for longer than 1 yr, either
because cardioversion has failed or because cardioversion has not
been attempted

5. CLASSIFICATION
• In addition to the previous AF categories, which are mainly defined
by episode timing and termination, the ACC/AHA/ESC guidelines
describe additional AF categories in terms of other characteristics of
the patient:
• Lone atrial fibrillation (LAF)—generally refers to AF in younger
patients (<60 yr old) who have normal echocardiographic findings
• Nonvalvular AF—absence of rheumatic mitral valve disease, a
prosthetic heart valve, or mitral valve repair
• Secondary AF—occurs in the setting of a primary condition that may
be the cause of the AF, such as acute myocardial infarction, cardiac
surgery, pericarditis, myocarditis, hyperthyroidism, pulmonary
embolism, pneumonia, or other acute disease. It is considered
separately because AF is less likely to recur once the precipitating
condition has resolved.

6. ACUTE MANAGEMENT

7. MANAGEMENT
The first step in management is to determine whether the patient is
stable or not…
-Look for any hemodynamic instability such as hypotension
-Is the patient responsive?
-Are there any mental status changes?
-are symptoms persistent and unbearable?

8. INITIAL MANAGEMENT DECISION
afib Unstable
Urgent
Cardiovert
Stable
Rate vs
rhythm
Control
Anticoagulate**

9. URGENT MANAGEMENT
Three circumstances for which urgent or emergent cardioversion may
be needed include:
●Active ischemia (symptomatic [eg, angina] or electrocardiographic
evidence).
●Evidence of organ hypoperfusion (eg, cold clammy skin, confusion,
acute kidney injury).
●Severe manifestations of heart failure (eg, pulmonary edema)

10. URGENT MANAGEMENT
Some patients’ clinical condition may improve quickly with urgent
rate control while others need to have sinus rhythm restored
immediately.
Clinical judgement is needed to determine whether rate control
should be tried or whether to proceed directly to cardioversion
Of equal importance is recognition that cardioversion in patients who
have been in AF for 48 hours or longer, or of unknown duration, is
associated with an increased risk of stroke and should not be
performed in the absence of performing transesophageal
echocardiography to screen for thrombus or at least three weeks of
anticoagulation, unless the patient is critically ill and no alternatives
to cardioversion are available

11. In a patient with any of these indications for urgent cardioversion,
and no alternative treatment options and/or failure to respond to rate
control, the need for restoration of normal sinus rhythm takes
precedence over the need for protection from thromboembolic risk.
(benefit outweighs the risk (5-7%))
Intravenous anticoagulation with heparin or administration of a newer
oral anticoagulant (eg, dabigatran, apixaban, or rivaroxaban) should
be started, but it should not cause a delay in emergent cardioversion.

12. STABLE PATIENTS

13. STABLE PATIENT
•Perform a complete history and physical examination, including an attempt
to obtain old records that might contain information about prior
supraventricular arrhythmias. The history is particularly helpful in the
decision to pursue a rate or a rhythm control strategy
•Risk factors for AF, as well as disease associations, may be identified. Old
records should be searched for evidence of a prior episode of AF or other
atrial tachyarrhythmias.
•Identify associated comorbidities that may place a patient at risk of stroke or
bleeding.
•A 12-lead electrocardiogram (ECG) should be performed to verify the
diagnosis of AF and assure that ongoing ischemia is not present on the ECG.
Old records should be searched for evidence of a prior episode of AF or
other atrial tachyarrhythmias.
•Order laboratory tests including electrolytes, cardiac markers

14. STABLE PATIENT
●Start a ventricular rate slowing drug for patients in whom this is
indicated.
● For patients with a rapid ventricular response, who manifest
symptoms or signs of hypoperfusion, rate control (or cardioversion)
may be needed urgently.
●Determine the need for anticoagulant therapy based on an
assessment of stroke and bleeding risks.
●Discuss with the patient the cause (if known), prognosis, and natural
history of AF.
●Consult a cardiologist or electrophysiologist (if needed).
●Schedule follow-up.

15. WORKUP
Laboratory Tests
• Thyroid-stimulating hormone, free T 4
• Serum electrolytes
• Toxicity screen
• CBC count (looking for anemia, infection)
• Cardiac enzymes—CK and/or troponin level (to investigate
cardiomyopathies or myocarditis and myocardial infarction)
• BNP (to evaluate for CHF)
• D-dimer/CT scan of chest PE protocol (if the patient has risk factors to
merit a pulmonary embolism workup)

16. RATE VS RHYTHM CONTROL
Rate Control vs Rhythm Control
**no clear survival benefit in rate vs rhythm control**

17. RATE CONTROL
For most patients with new onset atrial fibrillation (AF) and who are in
AF at the time of presentation, rate control will precede any attempt
to restore sinus rhythm; the principal exception is patients who are
hemodynamically unstable
In patients with mild to moderate symptoms, slowing the rate often
results in significant improvement or even resolution of symptoms.

18. RATE CONTROL
We believe that attempting to get the rate below 85 beats per minute
at rest is reasonable in symptomatic patients.
For patients who continue with unacceptable symptoms at this goal,
an attempt should be made to see if a lower rate goal lessens
symptoms.
For asymptomatic patients with permanent AF, a more lenient rate
control goal of <110 beats/min may be reasonable

19. RATE CONTROL
Agents:
Beta Blocker: Metoprolol and Propranolol,bisoprolol (ICU=esmolol gtt)
Non-dihydropyridine CA blockers: verapamil & Diltiazem (ICU=diltiazem
gtt)
Digoxin

20. DRUG SELECTION
The drug selected and the route of administration (oral versus
intravenous) are dictated by the clinical presentation:
•Beta blockers or verapamil or diltiazem are the preferred to digoxin in
the absence of heart failure (HF).
•Intravenous or oral amiodarone may help control rate when the other
drugs are ineffective or cannot be given.
•Digoxin is the preferred drug only in patients with AF due to HF.
Digoxin can also be used in patients who cannot take or who respond
inadequately to beta blockers or calcium channel blockers. The effect
of digoxin is additive to both of these drugs.

21. DRUG SELECTION
The choice among a beta blocker, diltiazem, and verapamil is frequently
based upon physician and patient preference, although it may be influenced
by other medical problems that are present.
As an example, beta blockers are particularly useful when the ventricular
response increases to inappropriately high rates during exercise, after an
acute myocardial infarction, and when exercise-induced angina pectoris is
also present.
Intravenous beta blockade is more effective than intravenous calcium
channel blockade for rate control , especially after cardiac surgery.
If there is a question about tolerance of the beta blocker, a drug with a short
half-life would be recommended.
On the other hand, a calcium channel blocker is preferred in patients with
chronic obstructive pulmonary disease and asthma.

24. RHYTHM CONTROL

25. RESTORATION OF SINUS RHYTHM
• In patients with recent onset atrial fibrillation (AF), who are
hemodynamically stable (with only mild to moderate symptoms) and
whose rate has been controlled (as discussed above), a decision
needs to be made regarding the restoration of sinus rhythm.
•We believe that most patients with symptomatic new onset AF and
most patients with apparently asymptomatic AF should have at least
one attempt at cardioversion (either electrical or chemical) to sinus
rhythm.

26. RESTORATION OF SINUS RHYTHM
Circumstances in which it is reasonable to not attempt cardioversion
in a patient with new onset AF include:
●Patients who are completely asymptomatic, particularly those who
are very elderly (>80 years) with multiple comorbidities, where risks
of undergoing cardioversionand/or pharmacologic rhythm control
may outweigh the benefits of restoring sinus rhythm.

27. REASONS TO NOT CARDIOVERT
●Low likelihood of successful cardioversion or maintenance of SR
after cardioversion:
•AF has been present continuously for more than one year
•The left atrium is markedly enlarged (atrial dimension >5.0 cm;
atrial volume >40 mL/m2)
•Patients who had recurrence while taking adequate doses of
appropriate antiarrhythmic drug therapy and have recently undergone
cardioversion. Drug refractory patients may have successful
conversion to SR but are less likely to maintain SR long term.
•Cardioversion with long-term maintenance of SR is likely to be
unsuccessful if the underlying cause (eg, thyrotoxicosis, pericarditis,
and mitral valve disease) for the AF has not been corrected prior to
cardioversion.

28. TIMING
•There is a low risk of systemic embolization if the duration of the
arrhythmia is 24 to 48 hours or less and there are no cardiac
abnormalities (particularly mitral valve disease or significant left
ventricular enlargement due to a cardiomyopathy) on transthoracic
echocardiography.
• Most patients with new onset AF of longer than 48 hours duration
should have cardioversion postponed until:
 Three weeks of anticoagulation has been achieved
Or
 A transesophageal has been performed and shows no left atrial
appendage clots

29. ELECTRICAL VERSUS
PHARMACOLOGIC
CARDIOVERSION
1. The choice of electrical or pharmacologic cardioversion depends
upon the comfort of the clinician to use one or the other approach.
2. For first episodes, electrical cardioversion is preferred.
3. In some patients, antiarrhythmic drugs are administered prior to
cardioversion to increase the chance of successful reversion and to
prevent early, intermediate, and late recurrence.
4. For patients with paroxysmal episodes of AF, drug therapy is
preferred if they will have sinus rhythm maintained with long-term
antiarrhythmic drug therapy, and as patients with paroxysmal AF
will likely convert anyway with or without electrical cardioversion.

30. ELECTRICAL VERSUS
PHARMACOLOGIC
CARDIOVERSION
• In the acute setting, pharmacologic cardioversion (e.g., ibutilide,
dofetilide) is less commonly used than electrical cardioversion.
•A major disadvantage with pharmacologic cardioversion is the risk of
development of ventricular tachycardia and other serious
arrhythmias, especially due to acute prolongation of the QT interval.

31. ELECTRICAL CARDIOVERSION
●Synchronized DC cardioversion should be performed while the
patient is under the influence of procedural sedation and is having
blood pressure, heart rate, oxygen saturation, and CO2 capnography
monitored.
Generally, cardioversion should be done in a situation where airway
equipment and airway expertise are present.

32. PHARMACOLOGIC CARDIOVERSION
As mentioned before, some patients have antiarrhythmic drugs
started before direct current (DC) cardioversion
Rarely, an attempt at cardioversion with an antiarrhythmic drug alone
can be appropriate, such as those for whom the risk of anesthesia is
high.
Flecainide, propafenone, ibutilide, dofetilide, and, to a lesser
degree, amiodarone all have efficacy for pharmacologic conversion of
atrial fibrillation (AF).
Of these, we prefer flecainide or propafenone unless the duration of
AF is greater than seven days, in which case dofetilide, or, to a lesser
degree, amiodarone or ibutilide have some role for medical
conversion.

33. PHARMACOLOGIC CARDIOVERSION
Flecainide — Flecainide is a very effective antiarrhythmic drug for the
pharmacologic conversion of a patient with AF of short (<24 hours)).
Flecainide should not be used in patients with structural heart
disease, particularly those with left ventricular systolic dysfunction
and in those with coronary artery disease.

34. PHARMACOLOGIC CARDIOVERSION
Propafenone — Propafenone is significantly more effective in
paroxysmal as opposed to persistent AF, with rates likely
approaching those seen with flecainide
As with flecainide, we do not suggest using propafenone in patients
with structural heart disease, particularly those with left ventricular
systolic dysfunction and those with coronary artery disease.

35. PHARMACOLOGIC CARDIOVERSION
Amiodarone — Cardioversion with either intravenous or
oral amiodarone is not particularly effective and occurs several hours
later than with flecainide, propafenone,ibutilide, and vernakalant
Intravenous amiodarone may be more effective in converting AF after
it has been given for hours and days.
Oral amiodarone requires long-term loading and is effective in
converting about 25 percent of patients with persistent AF to sinus
rhythm after six weeks of loading.
Thus, we do not recommend it solely for the purpose of
cardioversion.
It is not approved by the United States Food and Drug Administration
for the treatment of AF.

36. PHARMACOLOGIC CARDIOVERSION
However, amiodarone may occasionally have value before
cardioversion in patients who will receive the drug long term for
maintenance and may be considered as adjunctive therapy to increase
the likelihood of successful cardioversion in patients who are known
to be refractory to electrical cardioversion or in those in whom there
is a concern about early relapse.

37. PHARMACOLOGIC CARDIOVERSION
Vernakalant — Vernakalant is a relatively new antiarrhythmic drug
that has not been as extensively studied as all of the above agents.
It is available in Europe in intravenous forms for the rapid conversion
(50 percent conversion within 10 minutes) of recent-onset AF (≤7
days duration for patients not undergoing surgery, and ≤3 days
duration for post-cardiac surgery patients) to sinus rhythm

41. ANTICOAGULATION

42. ANTICOAGULATION
Most patients with new onset atrial fibrillation (AF) will revert to sinus
rhythm spontaneously or undergo an attempt at cardioversion.
●For patients with AF of more than 48 hours (or unknown) duration,
we recommend at least three weeks of oral anticoagulation prior to
cardioversion, and four weeks or more of anticoagulation following
cardioversion.
For patients in whom more urgent restoration of sinus rhythm is
desirable for a variety of reasons (including hemodynamic
compromised symptoms, difficult rate control, or patient
convenience), an alternative strategy is to perform a transesophageal
echocardiogram prior to cardioversion to rule out left atrial thrombi
and proceed to cardioversion if no thrombi are detected
(anticoagulate for at least four weeks after cardioversion).

43. ANTICOAGULATION
Anticoagulant therapy should be continued for at least 1 mo after
cardioversion to minimize the incidence of adverse thromboembolic
events. It can be stopped after 1 mo as long as AF has not recurred.
(independament du CHADS score)

44. ANTICOAGULATION
●For patients with AF of less than 48 hours duration, our reviewers
have differing approaches.
Some start unfractionated heparin, low molecular weight heparin, or a
newer oral anticoagulant prior to cardioversion in all patients, while
some proceed without anticoagulation in patients with AF of very
short duration who have a low stroke risk profile.
●For patients with a first episode of AF, our experts have differing
approaches to the decision regarding long-term anticoagulation.
Most anticoagulate based on risk, as determined by the CHA2DS2-
VASc score
However, some will not anticoagulate after a first episode, particularly
if a reversible cause has been identified.

46. CHRONIC MANAGEMENT

47. RATE VS RHYTHM
Per the AFFIRM and RACE trials, either rate control or rhythm control
strategies show no difference in composite cardiovascular end points
of death, CHF, bleeding, drug side effects, or thromboembolism.
Both approaches have similar outcomes as long as appropriate
anticoagulation is maintained based on the individual’s stroke risk.

48. RATE CONTROL
For patients without symptomatic AF, rate-control strategy with
calcium channel blockers, beta-blockers, or digoxin is a reasonable
option.
RACE 2 trial indicates that a lenient rate control strategy, with a target
resting heart rate of <110 beats/min is non inferior for a composite
primary end point that included CV death, heart-failure
hospitalization, stroke, and other major events over a median 3-yr
follow-up as compared to a strict control strategy, with a target
resting heart rate of <80 beats/min and an exercise heart rate of
<110 beats/min.

49. RHYTHM
• In patients with symptomatic AF, younger patients, or those with
difficult to control heart rate, attempt should be made to maintain
sinus rhythm with antiarrhythmic agents.
Options of antiarrhythmic agents include amiodarone, dronedarone,
(paroxysmal atrial fibrillation only without heart failure), dofetilide,
flecainide, propafenone (contraindicated with structural heart
disease), procainamide, or sotalol.
Use of dronedarone should be avoided in patients with persistent
and/or permanent atrial fibrillation due to worsened cardiovascular
outcomes, especially in those with concomitant symptomatic heart
failure

53. ANTICOAGULATION
The decision whether to pursue long-term anticoagulation must be
made in light of the patient’s risk for a cardioembolic event versus
risk for a bleeding event. The CHA2DS2-VASc has largely superseded
the CHADS2 scoring system

54. CHA2DS2-VASC
C = congestive heart failure;
H = hypertension;
A = age (>75 years is 2 points);
D= diabetes;
S= stroke, transient ischemic attack, or thromboembolic disease (2 points);
V = vascular disease,
A = age 65-74 years; and
Sc = sex category, with females getting 1 extra point).
Patients with a CHA2DS2-VASc score of 0 are considered low risk, 1 to 2 are
considered moderate risk, and >2 are considered high risk and would
benefit from long-term anticoagulation (e.g., warfarin).

55. ANTICOAGULATION STRATEGY
Anticoagulation with warfarin is generally not recommended in
patients with CHADS-VASc score of >1 (other than for female), there
is mounting evidence of benefit for anticoagulation.
Increasing amounts of evidence now show that aspirin likely does not
protect a person from stroke in AF and has recently been dropped
from the European Atrial Fibrillation guidelines.
Target INR for patients with a CHADS-VASc score of >2 is 2 to 3 and
should be diligently monitored to avoid risk of stroke versus
bleeding.
Patients with hypertrophic cardiomyopathy or thyrotoxicosis with AF
also have a high risk of stroke and should be anticoagulated
irrespective of their CHADS-VASc score.

56. COUMADIN
For CHAD2S2-VASc- score 2 or greater
Goal INR= 2 to 3
Must monitor INRs regularly
Can be dangerous if fall risk or bleeding risk high

57. DABIGATRAN
Direct Thrombin Inhibitor
RE-LY Trial showed superior to warfarin in preventing ischemic and
hemorrhagic CVAs with reduced risk of life threatening bleeding but
higher risk of GI bleeds
No lab monitoring*
No reversal agent available for major bleeding events

58. RIVAROXABAN
Oral factor Xa inhibitor
Seems to be equivalent in efficacy to warfarin for CVA prevention and
no difference in major bleeding events
Demonstrates a reduction in intracranial hemorrhage
Note: risk of thrombotic events increased for 28 days after stopping
drug so may need to bridge with another anticoagulant during this
time.

59. CASE VIGNETTE
This is a 65 y/o M who presents to the ED with dizziness, shortness
of breath, and palpitations which began approximately two hours ago
when he was playing catch with his grandson. No syncope or chest
pain.
On exam: He is afebrile with a BP=110/55, HR=110-162 bpm, and
respiratory rate of 25. A&Ox4 w/ NAD. Cardiac exam reveals
tachycardia with an irregularly irregular rhythm.
How would you approach the initial management of this patient?