Atrial fibrillation resident survival guide: Difference between revisions
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== Management== | == Management== | ||
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{{familytree | {{familytree | | A01 | | A01=<div style="text-align: left; width: 27em; padding:1em;"> '''Characterize the symptoms:'''<br> | ||
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<tr class="v-firstrow"><td>❑ Asymptomatic </td><td>❑ [[Palpitations]]</td><td>❑ [[Dyspnea]] </td></tr> | <tr class="v-firstrow"><td>❑ Asymptomatic </td><td>❑ [[Palpitations]]</td><td>❑ [[Dyspnea]] </td></tr> | ||
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❑ Frequency | ❑ Frequency | ||
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{{familytree | {{familytree | | B01 | | | B01= <div style="text-align: left; width: 27em; padding:1em;"> '''Identify possible triggers:'''<br> | ||
<table> | <table> | ||
<tr class="v-firstrow"><td>❑ [[Infection]]</td><td>❑ [[Caffeine]]</td><td>❑ [[Alcohol]]</td></tr> | <tr class="v-firstrow"><td>❑ [[Infection]]</td><td>❑ [[Caffeine]]</td><td>❑ [[Alcohol]]</td></tr> | ||
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<tr><td>❑ [[Pumonary embolism]]</td><td> [[Coronary thrombosis]]</td><td> [[Trauma]] </td></tr></table> | <tr><td>❑ [[Pumonary embolism]]</td><td> [[Coronary thrombosis]]</td><td> [[Trauma]] </td></tr></table> | ||
</div>}} | </div>}} | ||
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{{familytree | {{familytree | | C01 | | C01= <div style="text-align: left; width: 27em; padding:1em;"> ❑ Examine the patient <br> ❑ Order an [[EKG]] </div>}} | ||
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Revision as of 17:51, 5 March 2014
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]
Definitions
Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia, characterized by uncoordinated atrial activation and improper atrio-ventricular mechanical function.
Primary AF is classified as shown below:
Term | Definition |
---|---|
Paroxysmal | AF lasting < 7 days (most last < 24 hours). Usually self terminating. |
Persistent | AF lasting > 7 days. Usually does not terminate on its own. |
Permanent | AF lasting for a longer period, where in attempted cardioversion has failed or promises no improvement. |
Lone AF | AF in patients > 60 years, without any pre-existing cardiopulomunary diseases. |
Causes
Life Threatening Causes
Life-threatening causes include conditions which may result in death or permanent disability within 24 hours if left untreated.
- Congestive heart failure
- Dehydration
- Electrolyte disturbance
- Hypothermia
- Hypoxia
- Myocardial infarction[1]
- Myocarditis
- Pericarditis
- Pheochromocytoma
- Pulmonary embolism[2]
- Uremic pericarditis
Common Causes
Management
Characterize the symptoms:
Characterize the timing of the symptoms: | ||||||||||||||||||
Identify possible triggers: | ||||||||||||||||||
❑ Examine the patient ❑ Order an EKG | ||||||||||||||||||
Newly Discovered Atrial Fibrillation
Shown below is an algorithm depicting the pharmacological management of patients with newly discovered atrial fibrillation:
Newly discovered AF | |||||||||||||||||||||||||||||||||||||||||||
Paroxysmal AF | Persistent AF | ||||||||||||||||||||||||||||||||||||||||||
❑ Look for the presence of one of these severe symptoms:
Severe symptoms absent: Severe symptoms present: ❑ Attempt direct-current cardioversion | Anticoagulation: ❑ Consider anticoagulation as needed based on the risk of stroke ❑ Click here for the risk of stroke and anticoagulation therapy Heart rate control: ❑ Control heart rate as an initial method to manage AF, and regulate ventricular output Click here for pharmacological agents and doses used to control heart rate | ||||||||||||||||||||||||||||||||||||||||||
Anticoagulation: ❑ Consider anticoagulation as needed based on the risk of stroke ❑ Click here for the risk of stroke and anticoagulation therapy ❑ Recommended in all cases except lone AF (I A) ❑ Measure INR weekly initially, then monthly when stable (I A) ❑ Reassess need for anticoagulation at periodic intervals (IIa C) | Antiarrhythmic therapy: ❑ Consider antiarrythmic therapy for maintenance of sinus rhythm Click here for recommended pharmacological agents used for maintenance of sinus rhythm | ||||||||||||||||||||||||||||||||||||||||||
Cardioversion: ❑ Attempt cardioversion ❑ Click here for drugs and doses used for pharmacological cardioversion ❑ If patient hemodynamically unstable or tachycardic attempt electric cardioversion ❑ If pharmacological cardioversion fails attempt electric cardioversion | |||||||||||||||||||||||||||||||||||||||||||
❑ Do not treat with long term antiarrythmic therapy, unless indicated. | |||||||||||||||||||||||||||||||||||||||||||
Recurrent Paroxysmal Atrial Fibrillation
Shown below is an algorithm depicting the pharmacological management of patients with recurrent paroxysmal atrial fibrillation:
Recurrent paroxysmal AF | |||||||||||||||||||||||||||||||||
Minimal or no symptoms | Disabling symptoms in AF | ||||||||||||||||||||||||||||||||
Anticoagulation: ❑ Consider anticoagulation as needed based on the risk of stroke ❑ Click here for the risk of stroke and anticoagulation therapy Heart rate control: ❑ Control heart rate as an initial method to manage AF, and regulate ventricular output Click here for pharmacological agents and doses used to control heart rate | Anticoagulation: ❑ Consider anticoagulation as needed based on the risk of stroke ❑ Click here for the risk of stroke and anticoagulation therapy Heart rate control: ❑ Control heart rate as an initial method to manage AF, and regulate ventricular output Click here for pharmacological agents and doses used to control heart rate | ||||||||||||||||||||||||||||||||
❑ Long term therapy for prevention of AF not needed | Antiarrhythmic therapy: ❑ Consider antiarrythmic therapy for maintenance of sinus rhythm Click here for recommended pharmacological agents used for maintenance of sinus rhythm | ||||||||||||||||||||||||||||||||
❑ Consider AF ablation if antiarrhythmic drug treatment fails | |||||||||||||||||||||||||||||||||
Recurrent Persistent Atrial Fibrillation
Shown below is an algorithm depicting the pharmacological management of patients with recurrent persistent atrial fibrillation:
Recurrent persistent AF | |||||||||||||||||||||||||||||||||
Minimal or no symptoms | Disabling symptoms in AF | ||||||||||||||||||||||||||||||||
Anticoagulation: ❑ Consider anticoagulation as needed based on the risk of stroke ❑ Click here for the risk of stroke and anticoagulation therapy Heart rate control: ❑ Control heart rate as an initial method to manage AF, and regulate ventricular output Click here for pharmacological agents and doses used to control heart rate | Anticoagulation: ❑ Consider anticoagulation as needed based on the risk of stroke ❑ Click here for the risk of stroke and anticoagulation therapy Heart rate control: ❑ Control heart rate as an initial method to manage AF, and regulate ventricular output Click here for pharmacological agents and doses used to control heart rate | ||||||||||||||||||||||||||||||||
Antiarrhythmic therapy: ❑ Consider antiarrythmic therapy for maintenance of sinus rhythm Click here for recommended pharmacological agents used for maintenance of sinus rhythm | |||||||||||||||||||||||||||||||||
❑ Perform electrical cardioversion as needed ❑ Pretreat with one of the following agents to reduce the risk of early recurrence of AF after cardioversion:
| |||||||||||||||||||||||||||||||||
❑ Continue anticoagulation therapy based on risk factor profile as above ❑ Continue antiarrhythmic therapy to maintain sinus rhythm as above | |||||||||||||||||||||||||||||||||
❑ Consider ablation for severely symptomatic recurrent AF after failure of ≥ 1 antiarrhythmic drug plus rate control | |||||||||||||||||||||||||||||||||
Permanent Atrial Fibrillation
Shown below is an algorithm depicting the pharmacological management of patients with permanent atrial fibrillation:
Permanent AF | |||||||||||||||||||||||||||||||
Anticoagulation: ❑ Consider anticoagulation as needed based on the risk of stroke ❑ Click here for the risk of stroke and anticoagulation therapy Heart rate control: ❑ Control heart rate as an initial method to manage AF, and regulate ventricular output Click here for pharmacological agents and doses used to control heart rate | |||||||||||||||||||||||||||||||
Antiarrhythmic Drug Therapy in Atrial Fibrillation
Shown below is an algorithm depicting the antiarrhythmic drug therapy for maintain sinus rhythm in patients with recurrent paroxysmal or persistent atrial fibrillation:
Maintenance of sinus rhythm | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
No (or minimal) heart disease | Hypertension | Coronary artery disease | Heart failure | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Dronedarone Flecainide Propafenone Sotalol | Substantial LVH | Dronedarone Dofetilide Sotalol | Amiodarone Dofetilide | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Amiodarone Dofetilide | Catheter ablation | No | Yes | Amiodarone | Catheter ablation | Catheter ablation | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Dronedarone Flecainide Propafenone Sotalol | Amiodarone | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Catheter ablation | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Amiodarone Dofetilide | Catheter ablation | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Drugs are listed alphabetically and not in order of suggested use.
The seriousness of heart disease progresses from left to right, and selection of therapy in patients with multiple conditions depends on the most serious condition present.
Following table summarizes the list of most commonly used drugs and their dosages for maintenance of sinus rhythm:
Drug | Dose |
---|---|
Amiodarone | 100 to 400 mg |
Disopyramide | 400 to 750 mg |
Dofetilide | 5000 to 1000 mcg |
Flecainide | 200 to 300 mg |
Procainamide | 1000 to 4000 mg |
Propafenone | 450 to 900 mg |
Quinidine | 600 to 1500 mg |
Sotalol | 160 to 320 mg |
Pharmacological Cardioversion
Cardioversion upto7 Days
Drug | Dosage | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Agents with proven efficacy | |||||||||||
Dofetilide (I A) |
| ||||||||||
Flecainide (I A) | Oral: 200 to 300 mg Intravenous: 1.5 to 3.0 mg/kg over 10 to 20 min | ||||||||||
Ibutilide (I A) | 1 mg over 10 min; repeat 1 mg when necessary | ||||||||||
Propafenone (I A) | Oral: 600 mg Intravenous: 1.5 to 2.0 mg/kg over 10 to 20 min | ||||||||||
Amiodarone (IIa A) | Oral:
Intravenous:
|
Cardioversion after 7 Days
Drug | Dosage | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Dofetilide (I A) |
| ||||||||||
Amiodarone (IIa A) | Oral:
Intravenous:
| ||||||||||
Ibutilide (IIa A) | 1 mg over 10 min; repeat 1 mg when necessary |
Drugs which enhance the efficacy of electric cardioversion when given prior to the procedure: (Level of recommendation: IIa B)
- Amiodarone
- Flecainide
- Ibutilide
- Propafenone
- Sotalol
Risk Factors for Stroke and Recommended Antithrombotic Therapy
Low Risk Factors | Moderate Risk Factors | High Risk Factors |
---|---|---|
Female gender | Age ≥ 75 years | Previous stroke, TIA or embolism |
Age 65-74 years | Hypertension | Mitral stenosis |
Coronary artery disease | Heart failure | Prosthetic heart valve |
Thyrotoxicosis | LV ejection fraction ≤ 35% | - |
- | Diabetes mellitus | - |
Risk Category | Recommended 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)* |
Pharmacological Agents for Heart Rate Control
Drug | Loading Dose | Maintenance Dose |
---|---|---|
Acute Setting | ||
Heart rate control in patients without accessory pathway | ||
Esmolol (I C) | 500 mcg/kg IV over 1 min | 60 to 200 mcg/kg/min IV |
Propanolol (I C) | 0.15 mg/kg IV | NA |
Metoprolol (I C) | 2.5 to 5 mg IV bolus over 2 min; up to 3 doses | NA |
Diltiazem (I B) | 0.25 mg/kg IV over 2 min | 5 to 15 mg/h IV |
Verampil (I B) | 0.075 to 0.15 mg/kg IV over 2 min | NA |
Heart Rate Control in patients with accessory pathway | ||
Amiodarone (IIa 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 (I B) | 0.25 mg IV each 2 h, up to 1.5 mg | 0.125 to 0.375 mg daily IV or orally |
Amiodarone (IIa C) | 150 mg over 10 min | 0.5 to 1 mg/min IV |
Non-Acute Setting and Chronic Maintenance Therapy | ||
Heart rate control | ||
Metoprolol (I C) | Same as maintenance dose | 25 to 100 mg twice a day, orally |
Propanolol (I C) | Same as maintenance dose | 80 to 240 mg daily in divided doses, orally |
Verampil (I B) | Same as maintenance dose | 120 to 360 mg daily in divided doses; slow release available, orally |
Diltiazem (I B) | Same as maintenance dose | 120 to 360 mg daily in divided doses; slow release available, orally |
Heart Rate Control in patients with heart failure and without accessory pathway | ||
Digoxin (I C) | 0.5 mg by mouth daily | 0.125 to 0.375 mg daily, orally |
Amiodarone (IIb C) | 800 mg daily for 1 wk, orally 600 mg daily for 1 wk, orally 400 mg daily for 4 to 6 wk, orally | 200 mg daily, orally |
Do's
Therapeutic agents for Atrial fibrillation
- No mortality benefit is evident from rhythm control over rate control.
- Rate control with beta blockers (metoprolol/lopressor, atenolol/tenormin) or non-dihydropyridine calcium channel blockers (diltiazem/cardizem, verapamil)is recommended in older patients with chronic AF or unknown duration. Digoxin can be used as a second line drug.
- For young symptomatic AF patients rhythm control is preferred over rate control. Rhythm control can be achieved by medications, synchronized cardioversion or both. If both these options fail, catheter based ablation is an option.
- Sotalol and Dofetelide - monitor QTc interval for prolongation for 48 hrs post initiation. QTc >= 500 or 15% above baseline may increase the risk of Torsades. Check daily EKG or EKG 2 hours post the drug dose.
- Amiodarone can cause bradycardia, hepatotoxicity, throtoxicity, pulmonary fibrosis, and retinopathy.
- Flecanide should be used with beta blockers as it may increases the risk of rapid AV nodal conduction. It also increases digoxin levels
- Hemodynamic stability is first priority, rate or rhythm control 2nd.
- Hypotension could be rate related so treatment should not be avoided.
Cardioversion
- Emergent cardioversion for hemodynamically unstable AF.
- If drug therapy fails, cardioversion with 100 joules of electricity is recomended.
- Prior to an elective cardioversion in patients who have been in AF > 48hrs or unknown duration, either a negative TEE or 3-4 weeks of anticoagulation is recommended.
- Post cardioversion 4 weeks of anticoagulation is recommended.
Don't
- Don't use Digoxin as a single agent for rate control.
- Don't use calcium channel blocker, beta blocker, and digoxin in atrial fibrillation patients with WPW
References
- ↑ 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) - ↑ 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)