How should I manage a patient with atrial fibrillation, including assessment of hemodynamic stability, anticoagulation, rate control, and rhythm control?

Management of Atrial Fibrillation

Immediate Hemodynamic Assessment

Perform immediate synchronized electrical cardioversion (≥200 J biphasic) without awaiting anticoagulation if the patient presents with hypotension (SBP <90 mmHg), acute pulmonary edema, ongoing chest pain with ECG ischemia, altered mental status, or cardiogenic shock. 1, 2 Give an IV heparin bolus concurrently if feasible. 1

If hemodynamically stable, proceed with the structured approach below. 1, 3

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Exclude Wolff-Parkinson-White Syndrome

Review the 12-lead ECG for delta waves (pre-excitation) before administering any AV-nodal blocking agent. 1, 3

• If WPW with pre-excited AF is present and the patient is stable: give IV procainamide (15 mg/kg over 20–30 min) or IV ibutilide (1 mg over 10 min). 2, 3
• If WPW with pre-excited AF and hemodynamically unstable: perform immediate DC cardioversion. 2, 3
• Never use adenosine, β-blockers, calcium-channel blockers, digoxin, or IV amiodarone in pre-excited AF—they can accelerate ventricular rate and precipitate ventricular fibrillation. 2, 3, 4

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Anticoagulation Strategy

Stroke Risk Assessment

Calculate the CHA₂DS₂-VASc score immediately: congestive heart failure (1 point), hypertension (1 point), age ≥75 years (2 points), diabetes (1 point), prior stroke/TIA/thromboembolism (2 points), vascular disease (1 point), age 65–74 years (1 point), female sex (1 point). 1, 2, 4

• Initiate oral anticoagulation for all patients with CHA₂DS₂-VASc ≥2 (men) or ≥3 (women). 1, 2, 4
• Consider anticoagulation for CHA₂DS₂-VASc = 1 (men) or = 2 (women) after individualized bleeding-risk assessment. 2

Choice of Anticoagulant

Prescribe a direct oral anticoagulant (apixaban, rivaroxaban, edoxaban, or dabigatran) as first-line therapy over warfarin, except in patients with mechanical heart valves or moderate-to-severe mitral stenosis. 1, 2, 4, 5

• DOACs reduce intracranial hemorrhage risk by 50% compared with warfarin and have predictable pharmacokinetics. 4
• If warfarin is used, target INR 2.0–3.0 with weekly monitoring during initiation and monthly monitoring once stable. 1, 4

Peri-Cardioversion Anticoagulation

For AF lasting >48 hours (or unknown duration), provide therapeutic anticoagulation for ≥3 weeks before elective cardioversion and continue for ≥4 weeks afterward, regardless of cardioversion success. 1, 2, 4

• Alternatively, perform transesophageal echocardiography (TEE) to exclude left-atrial thrombus; if negative, proceed with cardioversion after initiating heparin. 1, 2, 4
• Continue anticoagulation indefinitely based on CHA₂DS₂-VASc score, not on whether sinus rhythm is maintained—72% of strokes in the AFFIRM trial occurred in patients who had discontinued anticoagulation or had subtherapeutic INR. 1, 2, 4

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Rate-Control Strategy

Patients with Preserved Ejection Fraction (LVEF >40%)

First-line: IV metoprolol 2.5–5 mg over 2 min; repeat every 5 min up to three doses to achieve resting heart rate 80–110 bpm. 1, 2, 3, 4

• Metoprolol is preferred in acute coronary syndrome, thyrotoxicosis, or chronic stable heart failure because of proven mortality benefit. 2, 3
• Alternative when β-blockers are contraindicated (e.g., COPD, active bronchospasm): IV diltiazem 0.25 mg/kg over 2 min followed by continuous infusion 5–15 mg/h. 1, 2, 3, 4
• Low-dose diltiazem (≤0.2 mg/kg IV bolus) is as effective as standard 0.25 mg/kg but produces significantly less hypotension. 3

Patients with Reduced Ejection Fraction (LVEF ≤40%) or Heart Failure

Use only IV β-blockers (metoprolol dosing as above) or IV digoxin (0.25 mg, repeat up to cumulative 1.5 mg/24 h); avoid diltiazem and verapamil because of negative inotropic effects. 1, 2, 3, 4

• Bisoprolol, carvedilol, and long-acting metoprolol are the preferred β-blockers in heart failure. 3, 4
• In severe LV dysfunction with hemodynamic instability, IV amiodarone (150 mg over 10 min, then 1 mg/min infusion) may be employed. 2, 3

Rate-Control Targets

Target a lenient resting heart rate <110 bpm initially; pursue stricter control (<80 bpm) only if symptoms persist despite lenient control. 1, 2, 3, 4

• The RACE II trial demonstrated lenient rate control was non-inferior to strict control for clinical outcomes in patients with preserved LV function. 1, 4

Combination Therapy

If monotherapy fails, add digoxin to a β-blocker or calcium-channel blocker to improve rate control at rest and during exercise; monitor closely for bradycardia. 1, 2, 3, 4

• Never combine more than two of the following: β-blocker, digoxin, amiodarone—risk of severe bradycardia, third-degree AV block, and asystole. 2, 3, 4
• Digoxin alone is ineffective for acute rate control in high-catecholamine states (sepsis, thyrotoxicosis, exercise) and should never be used as monotherapy in paroxysmal AF. 2, 3, 4

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Rhythm-Control Indications

Consider rhythm-control strategies (antiarrhythmic drugs or catheter ablation) for patients who remain symptomatic despite adequate rate control, younger patients (<65 years) with new-onset AF, those with rate-related cardiomyopathy, or hemodynamically unstable patients. 1, 2, 4, 5

• Rhythm control does NOT reduce mortality compared with rate control and is associated with higher hospitalization rates and adverse drug effects in older patients—the AFFIRM, RACE, PIAF, STAF, and HOT CAFÉ trials all showed no survival advantage. 1, 4, 6
• Early rhythm control (within 1 year of AF onset) with antiarrhythmic drugs or catheter ablation reduces adverse cardiovascular outcomes in patients with early AF and cardiovascular comorbidities. 4, 5

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Antiarrhythmic Drug Selection (Based on Cardiac Structure & LVEF)

No Structural Heart Disease (Normal LVEF, No CAD, No LV Hypertrophy)

First-line: flecainide (200–300 mg oral or 1.5–2 mg/kg IV over 10 min) or propafenone (450–600 mg oral or 1.5–2 mg/kg IV over 10 min). 1, 2, 3, 4

• These agents must be avoided in patients with ischemic heart disease or significant structural heart disease because of pro-arrhythmic risk. 1, 4
• Outpatient "pill-in-the-pocket" strategy: single oral dose of flecainide (200–300 mg) or propafenone (450–600 mg) can be self-administered at home after safety is confirmed in a supervised hospital setting. 4

Coronary Artery Disease with LVEF >35%

Sotalol is preferred; requires hospitalization with continuous ECG monitoring for ≥3 days, dose adjusted to renal function (creatinine clearance). 1, 3, 4

• Sotalol should be avoided in patients with prolonged QT interval, renal impairment (CrCl <40 mL/min), or overt heart failure. 3

Heart Failure or LVEF ≤40%

Amiodarone or dofetilide are the only safe options because other antiarrhythmics carry high pro-arrhythmic risk. 1, 2, 3, 4, 5

• IV amiodarone dosing: 5–7 mg/kg over 1–2 h followed by infusion of 50 mg/h (max 1 g/24 h); conversion to sinus rhythm may be delayed 8–12 h. 4
• Amiodarone is reserved for second- or third-line use in patients without heart failure because of higher risk of extracardiac organ toxicity (thyroid, pulmonary, hepatic). 4

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Catheter Ablation

Catheter ablation is recommended as first-line therapy in patients with symptomatic paroxysmal AF to improve symptoms and slow progression to persistent AF. 5

• Catheter ablation is also recommended for patients with AF and heart failure with reduced ejection fraction (HFrEF) to improve quality of life, left ventricular systolic function, and reduce mortality and heart failure hospitalization. 5
• Catheter ablation is a second-line option after failure of antiarrhythmic drugs in persistent AF or when patients are unwilling/unable to take long-term medication. 1, 4

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Electrical Cardioversion

Synchronized electrical cardioversion (120–200 J biphasic) is the preferred method for patients with severe hemodynamic compromise. 2, 4

• Biphasic defibrillators achieve higher conversion efficacy than monophasic devices. 4
• The procedure should be performed under adequate sedation (e.g., IV midazolam and/or propofol) with continuous cardiac monitoring. 4

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Initial Diagnostic Work-Up

Obtain a 12-lead ECG to confirm AF (irregularly irregular rhythm, absent P waves), assess ventricular rate, and identify pre-excitation, bundle-branch block, or prior MI. 1, 4, 7

Obtain a transthoracic echocardiogram to evaluate left-atrial size, left-ventricular function, valvular disease, and exclude structural abnormalities. 1, 4, 7

Screen for reversible precipitants: hyperthyroidism, acute alcohol intoxication, pulmonary embolism, myocardial infarction, pericarditis, myocarditis, hypertensive crisis, obstructive sleep apnea, electrolyte abnormalities (hypokalemia, hypomagnesemia). 1, 4

Complete blood count, serum electrolytes, and thyroid, renal, and hepatic function tests. 1, 7

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Management of Permanent Atrial Fibrillation

When patient and physician agree that no further rhythm-restoration attempts will be made, focus exclusively on rate control and anticoagulation; rhythm-control interventions are omitted. 4

• Target a resting heart rate <110 bpm (lenient control); adopt stricter control only if symptoms persist. 4
• If maximal pharmacologic rate control fails, consider AV node ablation with pacemaker implantation. 1, 4
• In severely symptomatic permanent AF patients with heart-failure hospitalization, AV node ablation combined with cardiac resynchronization therapy is reasonable. 4

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Common Pitfalls to Avoid

• Never discontinue anticoagulation solely because sinus rhythm has been restored—stroke risk is determined by CHA₂DS₂-VASc score, not rhythm status. 2, 4
• Do not rely on digoxin alone for acute rate control—it is ineffective in high-catecholamine states. 2, 3, 4
• Do not use AV-nodal blockers in pre-excited (WPW) AF—they can precipitate ventricular fibrillation. 2, 3, 4
• Do not combine β-blockers with diltiazem or verapamil except under specialist supervision with ambulatory ECG monitoring for bradycardia. 4
• Do not use flecainide or propafenone in patients with ischemic heart disease or structural heart disease. 1, 4
• Do not delay thrombolysis for massive PE to "stabilize the rhythm first"—thrombolysis is the stabilizing intervention. 2