Atrial fibrillation resident survival guide

Jump to navigation Jump to search

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Vidit Bhargava, M.B.B.S [2]; Hilda Mahmoudi M.D., M.P.H.[3]; Priyamvada Singh, M.D. [4]; Rim Halaby, M.D. [5]

Synonyms and keywords: AF, Afib

Atrial fibrillation resident survival guide Microchapters
Overview
Classification
Causes
Management
Newly Discovered Atrial Fibrillation
Recurrent Paroxysmal Atrial Fibrillation
Recurrent Persistent Atrial Fibrillation
Permanent Atrial Fibrillation
Maintenance of Sinus Rhythm
Heart Rate Control
Anticoagulation Therapy
Pharmacological Cardioverion
Do's
Dont's

Overview

Atrial fibrillation is a supraventricular tachyarrhythmia characterized by uncoordinated atrial activation leading to an irregularly irregular rhythm and absent P waves on ECG. It can be a serious life threatening disorder as the irregular atrial rhythm may transpire into a rapid ventricular rhythm eventually leading to ventricular failure. It can occur in a heart with underlying structural heart defect or even in a structurally normal heart. It is characterized by palpitations, dyspnea, chest discomfort, syncope etc. and can be triggered by a number of conditions. A typical AF rhythm on EKG is characterized by irregularly irregular rhythm, absent P waves, atrial rate 400-700 beats/min. Treatment of a new onset AF depends on hemodynamic status of the patient. If unstable rapid DC cardioversion is attempted, else rate control and anticoagulation are the treatment of choice, followed by antiarrhythmic therapy.

Classification

Paroxysmal Atrial Fibrillation

Atrial fibrillation is paroxysmal when it lasts less than 7 days (mostly less than 24 hours) and is usually self terminating.

Persistent Atrial Fibrillation

Atrial fibrillation is persistent when it lasts more than 7 days and it usually does not terminate on its own.

Permanent Atrial Fibrillation

Atrial fibrillation is permanent when it lasts for a longer period and an attempted cardioversion has failed or promises no improvement.

Lone Atrial Fibrillation

Atrial fibrillation is said to be lone atrial fibrillation in patients more than 60 years of age and without any pre-existing cardiopulomunary diseases.

Causes

Life Threatening Causes

Atrial fibrillation can be a life-threatening condition and must be treated as such irrespective of the underlying cause.

Common Causes

Diagnosis

Shown below is an algorithm summarizing the initial approach to atrial fibrillation.

 
 
 
 
 
 
 
 
Characterize the symptoms:

❑ Asymptomatic
Palpitations
Dyspnea
Fatigue
Chest discomfort
Lightheadedness
Syncope/Presyncope
Tachycardia
❑ Weakness
Characterize the timing of the symptoms:
❑ Onset

❑ First episode
❑ Recurrent

❑ Duration
❑ Frequency
❑ Termination of the episode

❑ Spontaneous
❑ Medication use
❑ Not terminated
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Examine the patient:
Tachycardia
Hypotension - suggestive of ventricular dysfunction
Diaphoresis
Evidence of congestive heart failure
Tachycardia
Tachypnea
❑ Narrow pulse pressure
Jugular vein distention
Rales
Third heart sound (S3)
Gallop rhythm
Bilateral ankle edema

❑ Flutter waves in jugular vein
❑ Signs of embolization Pulmonary:

Dyspnea
Tachypnea
Chest pain
Hemoptysis

Arterial:

❑ Cold extremities
❑ Loss of distal pulsations
Pallor of the extremity
❑ Muscle pain/spasm in concerned area
❑ Weakness/lack of movement
Tingling and numbness

❑ Order an ECG
♦ Atrial fibrillation rhythm

❑ Irregularly irregular rhythm
❑ Absent P waves
❑ Atrial rate 400-700 beats/minute
❑ Ventricular rate 75-180 beats/minute


♦ Other signs on ECG

Left ventricular hypertrophy
Preexcitation
Bundle branch block
❑ Previous myocardial infarction
❑ Other types of arrhythmias
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

❑ Order a transthoracic echocardiogram
❑ Order blood tests (if AF has not been investigated before)

❑ Thyroid function
❑ Renal function
❑ Hepatic function
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
New onset paroxysmal AF

❑ First Episode
❑ Lasts less than 7 days

❑ Usually self terminating
 
New onset persistent AF

❑ First Episode
❑ Lasts more than 7 days

❑ Doesn't terminate on its own
 
Recurrent paroxysmal AF

❑ Previous history of AF
❑ Lasts less than 7 days

❑ May or may not be self terminating
 
Recurrent persistent AF

❑ Previous history of AF
❑ Lasts more than 7 days

❑ Needs medical or surgical management
 
Permanent AF

❑ Fibrillation present continuously

❑ Needs constant management
 


Newly Discovered Atrial Fibrillation

Shown below is an algorithm depicting the pharmacological management of patients with newly discovered atrial fibrillation based on the 2011 ACCF/AHA/HRS updates for the management of atrial fibrillation.[3]

 
 
 
Newly discovered AF
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Paroxysmal AF
 
 
 
Persistent AF
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Accept progression to permanent AF
 
Restore sinus rhythm
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

❑ Do not administer therapy unless the patient has any of the following symptoms requiring DC cardioversion

Hypotension
Heart failure
Angina pectoris

❑ Administer long term anticoagulation therapy based on the risk of stroke

❑ Measure INR weekly initially, then monthly when stable (class I, level of evidence A)
❑ Reassess need for anticoagulation at periodic intervals (class IIa, level of evidence C)
 

❑ Administer long term anticoagulation therapy based on the risk of stroke

❑ Control the ventricular rate
 

❑ Administer anticoagulation therapy based on the risk of stroke
❑ Administer rate control therapy

THEN

❑ Attempt for cardioversion

THEN

❑ Administer short term antiarrhythmic drugs

 

Note: For the treatment of newly persistent AF, choose the therapy depending on the severity of symptoms and the risk of administration of anti-arrhythmic.

Recurrent Paroxysmal Atrial Fibrillation

Shown below is an algorithm depicting the pharmacological management of patients with recurrent paroxysmal atrial fibrillation based on the 2011 ACCF/AHA/HRS updates for the management of atrial fibrillation.[3]

 
 
Recurrent paroxysmal AF
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Minimal or no symptoms
 
Disabling symptoms in AF
 
 
 
 
 
 
 
 
 
 
❑ Administer rate control

❑ Administer anticoagulation therapy based on the risk of stroke

❑ Avoid antiarrhythmic
 

❑ Administer rate control
❑ Administer anticoagulation therapy based on the risk of stroke
❑ Administer antiarrhythmic

❑ Sustained dose
❑ Pill in the pocket
 
 
 
 
 
 
 
 
 
 
 
 
 
❑ Consider AF ablation if antiarrhythmic treatment fails

Recurrent Persistent Atrial Fibrillation

Shown below is an algorithm depicting the pharmacological management of patients with recurrent persistent atrial fibrillation based on the 2011 ACCF/AHA/HRS updates for the management of atrial fibrillation.[3]

 
 
Recurrent persistent AF
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Minimal or no symptoms
 
Disabling symptoms in AF
 
 
 
 
 
 
 
 
 
 
❑ Administer rate control
❑ Administer anticoagulation therapy based on the risk of stroke
 

❑ Administer rate control
❑ Administer anticoagulation therapy based on the risk of stroke
❑ Administer antiarrhythmic

THEN

❑ Attempt for cardioversion
 
 
 
 
 
 
 
 
 
 
 
 
 
❑ Continue anticoagulation therapy
❑ Continue antiarrhythmic
 
 
 
 
 
 
 
 
 
 
 
 
 
In case of recurrence of AF, proceed with:

Left atrial ablation
Maze procedure

AV nodal ablation and pacing

Permanent Atrial Fibrillation

Shown below is an algorithm depicting the pharmacological management of patients with permanent atrial fibrillation based on the 20011 ACCF/AHA/HRS updates for the management of atrial fibrillation.[3]

Permanent AF
 
 
 
 
 

❑ Administer anticoagulation therapy based on the risk of stroke
❑ Administer rate control


Maintenance of Sinus Rhythm

Shown below is an algorithm depicting the antiarrhythmic drug therapy for maintaining sinus rhythm in patients with recurrent paroxysmal or persistent atrial fibrillation based on the 20011 ACCF/AHA/HRS updates for the management of atrial fibrillation. Drugs are listed alphabetically and not in order of suggested use.[3]

 
 
 
 
 
 
 
 
 
 
 
 
 
 
Maintenance of sinus rhythm
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
No or minimal heart disease
 
 
 
 
 
Hypertension
 
 
 
 
 
Coronary artery disease
 
 
 
Heart failure
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
First line therapy:
Dronedarone
Flecainide
Propafenone
Sotalol
 
 
 
 
 
Substantial LVH
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Second line therapy:
Amiodarone
Dofetilide
 
Catheter ablation
 
No
 
Yes
 
Amiodarone
 
Catheter ablation
 
Catheter ablation
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Amiodarone
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Catheter ablation
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Catheter ablation
 
 
 
 
 
 
 
 



Maintenance of Sinus Rhythm
Amiodarone (100 to 400 mg)
OR
Disopyramide (400 to 750 mg)
OR
Dofetilide (500 to 1000 mcg)
OR
Flecainide (200 to 300 mg)
OR
Procainamide (1000 to 4000 mcg)
OR
Propafenone (450 to 900 mg)
OR
Quinidine (600 to 1500 mg)
OR
Sotalol (160 to 320 mg)


Note:

Heart Rate Control

Shown below is a table summarizing the list of recommended agents for control of heart rate and their dosages.[3]

Heart Rate Control in Acute Setting
Drug Loading dose Maintenance dose
Heart rate control in patients without accessory pathway
Esmolol
(class I, level of evidence C)
500 mcg/kg IV over 1 min 60 to 200 mcg/kg/min IV
Propanolol
(class I, level of evidence C)
0.15 mg/kg IV NA
Metoprolol
(class I, level of evidence C)
2.5 to 5 mg IV bolus over 2 min; up to 3 doses NA
Diltiazem
(class I, level of evidence B)
0.25 mg/kg IV over 2 min 5 to 15 mg/h IV
Verapamil
(class I, level of evidence B)
0.075 to 0.15 mg/kg IV over 2 min NA
Heart rate control in patients with accessory pathway
Amiodarone
(class IIa, level of evidence C)
150 mg over 10 min 0.5 to 1 mg/min IV
Heart Rate Control in patients with heart failure and without accessory pathway
Digoxin
(class I, level of evidence B)
0.25 mg IV each 2 h, up to 1.5 mg 0.125 to 0.375 mg daily IV or orally
Amiodarone
(class IIa, level of evidence C)
150 mg over 10 min 0.5 to 1 mg/min IV
Heart Rate Control in Non Acute Setting and Long Term Maintenance
Heart rate control
Metoprolol
(class I, level of evidence C)
25 to 100 mg twice a day, orally 25 to 100 mg twice a day, orally
Propanolol
(class I, level of evidence C)
80 to 240 mg daily in divided doses, orally 80 to 240 mg daily in divided doses, orally
Verapamil
(class I, level of evidence B)
120 to 360 mg daily in divided doses, orally 120 to 360 mg daily in divided doses, orally
Diltiazem
(class I, level of evidence B)
120 to 360 mg daily in divided doses, orally 120 to 360 mg daily in divided doses, orally
Heart Rate Control in patients with heart failure and without accessory pathway
Digoxin
(class I, level of evidence B)
0.5 mg by mouth daily 0.125 to 0.375 mg daily, orally
Amiodarone
(class IIb, level of evidence C)
800 mg daily for 1 week, orally
600 mg daily for 1 week, orally
400 mg daily for 4 to 6 week, orally
200 mg daily, orally

Anticoagulation Therapy

Shown below are tables depicting the assessment of risk of stroke and the appropriate anticoagulation therapy among patients with AF.[3]

Anticoagulation Therapy
No risk factors Aspirin 81-325 mg daily
1 Moderate risk factor Aspirin 81-325 mg daily
OR
Warfarin (INR 2.0 to 3.0, target 2.5)
Any high risk factor or
more than 1 moderate risk factor
Warfarin (INR 2.0 to 3.0, target 2.5)


Low Risk Factors Moderate Risk Factors High Risk Factors
Female gender
Age 65-74 years
Coronary artery disease
Thyrotoxicosis
Age ≥ 75 years
Hypertension
Heart failure
LV ejection fraction ≤ 35%
Diabetes mellitus
Previous stroke, TIA or embolism
Mitral stenosis
Prosthetic heart valve

Pharmacological Cardioversion

Shown below is a table summarizing the pharmacological cardioversion for atrial fibrillation of a duration less or more than 7 days.[3]

Pharmacological Cardioversion for Atrial Fibrillation of a Duration Up to 7 Days
Drug Dosage
Dofetilide
(class I, level of evidence A)
Oral dose depends on creatinine clearance (ml/min):
> 60: 500 mg, BID
40 to 60: 250 mg, BID
20 to 40: 125 mg, BID
< 20: contraindicated
Flecainide
(class I, level of evidence A)
Oral: 200 to 300 mg
▸ Intravenous: 1.5 to 3.0 mg/kg, over 10 to 20 min
Ibutilide
(class I, level of evidence A)
Intravenous: 1 mg over 10 min, repeat 1 mg if necessary
Propafenone
(class I, level of evidence A)
Oral: 600 mg
▸ Intravenous: 1.5 to 2.0 mg/kg, over 10 to 20 min
Amiodarone
(class IIa, level of evidence A)
Oral:
Inpatient
1.2 to 1.8 g per day in divided dose until a maximum of 10 g
Followed by a maintenance dose of 200 to 400 mg per day or 30 mg/kg
Outpatient
600 to 800 mg per day divided dose until a maximum of 10 g
Followed by a maintenance dose of 200 to 400 mg per day

Intravenous:

5 to 7 mg/kg, over 30 to 60 min
Followed by 1.2 to 1.8 g per day continuous IV
OR
5 to 7 mg/kg, in divided oral doses until a maximum of 10 g
Followe by a maintenance dose of 200 to 400 mg per day
Pharmacological Cardioversion for Atrial Fibrillation of a Duration More Than 7 Days
Drug Dosage
Dofetilide
(class I, level of evidence A)
Oral dose depends on creatinine clearance (ml/min):
> 60: 500 mg, BID
40 to 60: 250 mg, BID
20 to 40: 125 mg, BID
< 20: contraindicated
Ibutilide
(class IIa, level of evidence A)
Intravenous: 1 mg over 10 min; repeat 1 mg when necessary
Amiodarone
(class IIa, level of evidence A)
Oral:
Inpatient
1.2 to 1.8 g per day in divided dose until a maximum of 10 g
Followed by a maintenance dose of 200 to 400 mg per day or 30 mg/kg
Outpatient
600 to 800 mg per day divided dose until a maximum of 10 g
Followed by a maintenance dose of 200 to 400 mg per day

Intravenous:

5 to 7 mg/kg, over 30 to 60 min
Followed by 1.2 to 1.8 g per day continuous IV
OR
5 to 7 mg/kg, in divided oral doses until a maximum of 10 g
Followe by a maintenance dose of 200 to 400 mg per day

Do's

Rate Control

Antithrombotic Therapy

Cardioversion

Dont's

References

  1. Zimetbaum, PJ.; Josephson, ME.; McDonald, MJ.; McClennen, S.; Korley, V.; Ho, KK.; Papageorgiou, P.; Cohen, DJ. (2000). "Incidence and predictors of myocardial infarction among patients with atrial fibrillation". J Am Coll Cardiol. 36 (4): 1223–7. PMID 11028474. Unknown parameter |month= ignored (help)
  2. Goldhaber, SZ.; Visani, L.; De Rosa, M. (1999). "Acute pulmonary embolism: clinical outcomes in the International Cooperative Pulmonary Embolism Registry (ICOPER)". Lancet. 353 (9162): 1386–9. PMID 10227218. Unknown parameter |month= ignored (help)
  3. 3.00 3.01 3.02 3.03 3.04 3.05 3.06 3.07 3.08 3.09 3.10 3.11 Fuster, V.; Rydén, LE.; Cannom, DS.; Crijns, HJ.; Curtis, AB.; Ellenbogen, KA.; Halperin, JL.; Kay, GN.; Le Huezey, JY. (2011). "2011 ACCF/AHA/HRS focused updates incorporated into the ACC/AHA/ESC 2006 guidelines for the management of patients with atrial fibrillation: a report of the American College of Cardiology Foundation/American Heart Association Task Force on practice guidelines". Circulation. 123 (10): e269–367. doi:10.1161/CIR.0b013e318214876d. PMID 21382897. Unknown parameter |month= ignored (help)


Template:WikiDoc Sources