What is the initial management of atrial fibrillation, including confirmation with ECG (electrocardiogram), assessment of symptoms, duration, underlying cardiac disease, stroke risk using CHA₂DS₂‑VASc (Congestive heart failure, Hypertension, Age ≥75 years (2 points), Diabetes mellitus, Stroke/TIA/thromboembolism (2 points), Vascular disease, Age 65–74 years, Sex category female), anticoagulation, and rate versus rhythm control strategies?

Initial Management of Atrial Fibrillation

For newly diagnosed atrial fibrillation, immediately obtain a 12-lead ECG to confirm the diagnosis, calculate the CHA₂DS₂-VASc score to determine stroke risk, initiate oral anticoagulation with a direct oral anticoagulant (DOAC) for scores ≥2 in men or ≥3 in women, and implement rate control with a beta-blocker as first-line therapy while addressing underlying cardiac disease and modifiable risk factors. 1, 2, 3

Diagnostic Confirmation

• A 12-lead ECG or single-lead ECG tracing of ≥30 seconds showing heart rhythm with no discernible repeating P waves and irregular RR intervals is required to establish the diagnosis of clinical AF. 1
• Review of the ECG by a physician is mandatory to provide a definite diagnosis and commence appropriate management. 1
• Document the type of AF: paroxysmal (self-terminating within 7 days), persistent (sustained >7 days), long-standing persistent (continuous >12 months), or permanent (joint decision to stop rhythm restoration attempts). 1

Symptom Assessment

• Evaluate AF-related symptoms including palpitations, fatigue, tiredness, exertional shortness of breath, and chest pain using the modified EHRA symptom scale before initiating treatment. 1
• Quantify symptom burden to inform shared decision-making and guide treatment choices between rate and rhythm control strategies. 1
• Reassess symptoms after major treatment changes to determine therapeutic efficacy. 1

Stroke Risk Stratification Using CHA₂DS₂-VASc

• Calculate the CHA₂DS₂-VASc score for every patient with newly diagnosed AF: Congestive heart failure (1 point), Hypertension (1 point), Age ≥75 years (2 points), Diabetes mellitus (1 point), prior Stroke/TIA/thromboembolism (2 points), Vascular disease (1 point), Age 65-74 years (1 point), and female Sex (1 point). 1, 2
• Score 0 (men) or 1 (women): No anticoagulation recommended; annual stroke risk is 0-0.6%. 2, 4
• Score 1 (men) or 2 (women): Oral anticoagulation should be considered; annual stroke risk is approximately 2.2-2.75%. 4, 5
• Score ≥2 (men) or ≥3 (women): Oral anticoagulation is a Class I indication; annual stroke risk ranges from 2.2% to >15% depending on total score. 1, 2, 4

Assessment of Underlying Cardiac Disease

• Obtain a transthoracic echocardiogram to assess: left ventricular ejection fraction (LVEF), left atrial size, valvular function (particularly to exclude rheumatic mitral stenosis or mechanical valves), and structural heart disease. 3
• Measure renal function (creatinine clearance), liver function, complete blood count, and thyroid function before initiating anticoagulation. 3
• Screen for hypertension (target BP <130/80 mmHg), heart failure, diabetes (target HbA1c <7%), and obstructive sleep apnea as these conditions worsen AF outcomes. 3

Anticoagulation Strategy

First-Line Therapy

• Initiate a direct oral anticoagulant (DOAC) as first-line therapy for non-valvular AF with CHA₂DS₂-VASc ≥2 (men) or ≥3 (women); this is a Class I, Level A recommendation that supersedes warfarin. 3, 4
• DOAC options include: Apixaban 5 mg twice daily (reduce to 2.5 mg twice daily if ≥2 of: age ≥80 years, weight ≤60 kg, creatinine ≥1.5 mg/dL), Rivaroxaban 20 mg once daily with food (reduce to 15 mg once daily if CrCl 30-50 mL/min), Dabigatran 150 mg twice daily (reduce to 75 mg twice daily if CrCl 15-30 mL/min), or Edoxaban (dose-adjusted per renal function). 3, 4

Special Populations

• End-stage chronic kidney disease (CrCl <15 mL/min) or dialysis: Dabigatran and rivaroxaban are contraindicated (Class III); use warfarin targeting INR 2.0-3.0 (Class IIa, Level B). 3, 4
• Mechanical heart valves: Warfarin is mandatory with target INR based on valve type and location; dabigatran is contraindicated (Class III, Level B). 1, 4
• Atrial flutter: Manage identically to AF using the same CHA₂DS₂-VASc thresholds and anticoagulation recommendations (Class I, Level C). 1, 2

Renal Function Monitoring

• Assess renal function before starting any DOAC and reassess at least annually (Class I, Level B). 3, 4
• More frequent monitoring is required during acute illness, medication changes, or in patients with heart failure. 3

Bleeding Risk Assessment

• Calculate the HAS-BLED score (Hypertension, Abnormal renal/liver function, Stroke, Bleeding history, Labile INR, Elderly >65 years, Drugs/alcohol) to identify modifiable bleeding risk factors. 4
• A HAS-BLED score ≥3 does not contraindicate anticoagulation but prompts more frequent monitoring and correction of modifiable factors (Class IIa, Level B). 3, 4
• Do not withhold anticoagulation solely because of fall risk; stroke risk outweighs traumatic intracranial hemorrhage risk. 3

Warfarin Alternative

• If warfarin is used, target INR 2.0-3.0 and check INR weekly during initiation, then monthly when stable (Class I, Level A). 1, 4
• Consider switching to a DOAC if unable to maintain therapeutic INR. 1

Rate Versus Rhythm Control Strategy

Rate Control (First-Line for Most Patients)

• Initiate a beta-blocker as first-line rate control therapy; beta-blockers are preferred because they provide mortality benefit in patients with heart failure beyond rate control (Class I, Level A). 3
• Target resting heart rate <110 bpm (lenient control) initially; tighten to <80 bpm only if symptoms persist despite lenient control (Class IIa). 3
• If beta-blocker alone is insufficient, add digoxin (Class IIa) while avoiding bradycardia. 3
• In patients with heart failure and reduced ejection fraction (HFrEF, LVEF ≤40%), calcium-channel blockers (diltiazem, verapamil) are contraindicated due to negative inotropic effects (Class III). 3

Rhythm Control Considerations

• For first-diagnosed AF lasting <48 hours, a "wait-and-see" approach is reasonable to allow spontaneous conversion (Class IIa). 3
• In symptomatic patients with persistent AF and underlying cardiac disease, rhythm control with cardioversion may be pursued (Class I). 3
• Regardless of successful cardioversion or maintenance of sinus rhythm, continue oral anticoagulation indefinitely because stroke risk (CHA₂DS₂-VASc) persists (Class I). 3

Comorbidity and Risk Factor Management (AF-CARE Pathway)

• Hypertension: Maintain optimal blood pressure <130/80 mmHg; prioritize ACE-inhibitor/ARB or beta-blocker therapy (Class I, Level A). 1, 3
• Diabetes: Target HbA1c <7%; incorporate SGLT2 inhibitors, which reduce heart failure hospitalizations and cardiovascular mortality (Class I, Level A). 3
• Heart failure with reduced ejection fraction: Implement guideline-directed medical therapy including beta-blocker, ACE-inhibitor/ARB/ARNI, mineralocorticoid receptor antagonist, and SGLT2 inhibitor (Class I, Level A). 3
• Weight management: Weight loss is recommended as part of comprehensive risk factor management in overweight and obese individuals (BMI >25 kg/m²) to reduce symptoms and AF burden, with a target of 10% or more reduction in body weight (Class I, Level B). 1, 3
• Lifestyle modifications: Maintain an active lifestyle equivalent to 150-300 minutes per week of moderate intensity or 75-150 minutes per week of vigorous intensity aerobic physical activity; avoid binge drinking and alcohol excess (Class I, Level B). 1

Structured Follow-Up and Reassessment

• Schedule formal reassessment at 6 months after initial presentation, then at least annually (or more frequently based on clinical need) (Class I). 3
• At each visit obtain: 12-lead ECG (rhythm and rate), laboratory panel (renal and liver function, CBC, thyroid), transthoracic echocardiography (LVEF, LA size, valve assessment), and ambulatory ECG monitoring if symptoms suggest paroxysmal AF or inadequate rate control (Class I). 3
• Recalculate CHA₂DS₂-VASc and HAS-BLED scores to capture new risk factors and adjust management accordingly. 3

Common Pitfalls to Avoid

• Do not use aspirin as an alternative to anticoagulation in patients with CHA₂DS₂-VASc ≥2; aspirin is ineffective for stroke prevention in AF and still carries bleeding risk (Class III). 3, 4
• Do not discontinue anticoagulation after successful cardioversion or ablation; stroke risk remains unchanged (Class I). 3
• Do not prescribe dabigatran or rivaroxaban in end-stage CKD or dialysis; these are contraindicated (Class III). 3, 4
• Do not aim for strict rate control (<80 bpm) as the initial target; begin with lenient control (<110 bpm) to avoid worsening heart failure symptoms (Class IIa). 3
• Do not combine anticoagulation with dual antiplatelet therapy unless a specific indication exists, and limit duration with gastroprotection (Class IIb). 3