Atrial Fibrillation (AF) 💓 ✅

AF and Anticoagulation ✅

🧠 Stroke Risk Assessment in AF

• 📊 Use CHA₂DS₂-VASc for non-valvular AF to guide anticoagulation.
• 💊 Warfarin reduces stroke risk by ~66%; DOACs offer similar or better stroke protection with lower ICH risk.
• 🩸 Assess bleeding risk using HAS-BLED. High score prompts review of modifiable factors, not withholding anticoagulation.

🧮 CHADS₂ Score

• 💔 Congestive heart failure/LV dysfunction: +1
• 🩺 Hypertension: +1
• 🎂 Age ≥ 75 years: +1
• 🍬 Diabetes mellitus: +1
• 🧠 Prior Stroke/TIA: +2

📈 CHADS₂ Event Rates

• 0–1: ⚖️ 1.9–2.8% per 100 patient-years
• 2–4: 📉 4.0–5.9% per 100 patient-years
• 5–6: 🚨 12.5–18.2% per 100 patient-years

🧮 CHA₂DS₂-VASc Score

• 💔 CHF/LV dysfunction: +1
• 🩺 Hypertension: +1
• 🎂 Age ≥ 75: +2
• 🎂 Age 65–74: +1
• 🍬 Diabetes mellitus: +1
• 🫀 Vascular disease (MI, PAD, aortic plaque): +1
• 🧠 Prior Stroke/TIA/TE: +2
• 👩 Female sex: +1

📊 CHA₂DS₂-VASc Event Rates

• 0–1: ⚖️ Low risk, 0–1.6% per 100 pt-years
• 2–4: 📉 Moderate risk, 2–6% per 100 pt-years
• ≥5: 🚨 High risk, 8–15% per 100 pt-years

💊 Anticoagulation Recommendations (NICE NG196)

• Score 0: 🚫 No anticoagulation
• Score 1 (male): 🤔 Consider anticoagulation
• Score 1 (female, only sex-related): ❌ No anticoagulation
• Score ≥2: ✅ Anticoagulation recommended
• 💊 First-line: DOACs (apixaban, rivaroxaban, dabigatran, edoxaban)
• ⚠️ Warfarin: Only for mechanical valves, moderate/severe mitral stenosis, or DOAC contraindications
• 🩺 Adjust DOAC dose for renal impairment or low body weight

🩹 Bleeding Risk Assessment (HAS-BLED)

• H – Hypertension uncontrolled: +1
• A – Abnormal renal/liver function: +1 each
• S – Stroke history: +1
• B – Bleeding tendency or predisposition: +1
• L – Labile INR (if on warfarin): +1
• E – Elderly (age >65): +1
• D – Drugs/alcohol: +1 each

⚠️ High HAS-BLED score (≥3) → review modifiable risk factors, do NOT automatically withhold anticoagulation.

💊 Anticoagulant Options

🔑 Clinical Pearls

• Bleeding and stroke risks overlap – don’t use HAS-BLED to deny anticoagulation; instead use it to mitigate risks.
• DOACs are preferred first-line (NICE NG196, 2021) unless contraindicated (e.g. valvular AF, severe renal impairment).
• Warfarin still used in mechanical valves or severe mitral stenosis.
• Reversal agents are now available for both warfarin and DOACs.

🩺 Case Examples

Case 1 – Young Patient, Low Stroke Risk

58-year-old man with paroxysmal AF, no hypertension, diabetes, heart failure, or vascular disease. CHA₂DS₂-VASc = 0 Management: 📝 No anticoagulation needed. Focus on lifestyle optimization: BP, weight, alcohol, OSA. Rationale: ⚖️ Stroke risk very low (<1%/year), anticoagulation not beneficial.

Case 2 – Older Patient with Risk Factors

74-year-old woman with persistent AF, hypertension, type 2 diabetes. CHA₂DS₂-VASc = 4 Management: 💊 Start anticoagulation (DOAC preferred; warfarin if renal dysfunction). Monitor renal function and bleeding risk. Rationale: ✅ High stroke risk, anticoagulation provides substantial benefit (~65% relative risk reduction).

Case 3 – Frail Patient with Falls

82-year-old man, permanent AF, previous TIA, hypertension, moderate frailty, history of falls. CHA₂DS₂-VASc = 5; HAS-BLED = 3 Management: ⚖️ Anticoagulation still offered (DOAC at adjusted dose preferred). Review medications, monitor renal function, fall risk mitigation. Rationale: ✅ Stroke risk outweighs bleeding risk; falls alone rarely contraindicate anticoagulation.

🛠️ Rate & Rhythm Control Overview

• 🎛️ Rate control: β-blockers (bisoprolol, metoprolol), non-DHP CCBs (diltiazem, verapamil), digoxin (esp. in HF)
• 🎯 Target HR: <110 bpm (lenient) or <80 bpm if symptomatic)
• 🔄 Rhythm control: consider in symptomatic or younger patients
• 💊 Antiarrhythmics: Class I (flecainide, propafenone) if no structural heart disease; Class III (amiodarone, sotalol) if structural disease present
• ⚡ Electrical cardioversion (DCCV) under sedation if acute onset or unstable
• 🔥 Catheter ablation for recurrent symptomatic AF

🌱 Lifestyle & Comorbidity Management

• 🏃 Encourage moderate exercise; avoid excess high-intensity activity
• 🍷 Limit alcohol
• 💤 Treat OSA (CPAP), optimise sleep hygiene
• 📉 Control BP and diabetes
• ⚖️ Weight management
• 🚭 Smoking cessation

📚 References

• NICE NG196: Atrial fibrillation (2021)
• 2019 AHA/ACC/HRS AF Guidelines
• CHA₂DS₂-VASc Validation Study

Atrial Fibrillation and Rhythm Control ✅

📌 Indications

• Fast AF with haemodynamic instability (shock, hypotension, chest pain, pulmonary oedema).
• Recent AF (<3 months) where rhythm control is desirable.
• Young patient without structural heart disease.
• Persistent symptoms despite rate control.
• ⚠️ Relapse risk: 80–90% at 1 year.

🚨 Emergency Cardioversion

• If already anticoagulated → low risk → proceed directly.
• If not anticoagulated and AF >24–48h → TOE/TEE to exclude LA thrombus (if feasible).
• If unstable → immediate DC cardioversion regardless of anticoagulation status (anticoagulate after).

⚡ Cardioversion Options

• Treat reversible causes first (sepsis, thyroid disease, alcohol, electrolytes).
• Anticoagulate with LMWH or DOAC (start before or immediately after cardioversion).
• Option 1: DC Cardioversion
  • Synchronised DC shock under sedation or GA.
  • Preferred in haemodynamically unstable AF or where drug therapy fails.
• Option 2: Chemical Cardioversion
  • Flecainide 2 mg/kg IV (max 150 mg) over 30–60 min or 300 mg PO. ⚠️ Only if normal LV and no significant IHD.
  • Amiodarone IV: preferred in LV dysfunction or structural heart disease.
• Post-cardioversion: Anticoagulate for ≥4 weeks even if sinus rhythm restored.

🔄 Rhythm Control Principles

• Immediate cardioversion possible if AF <48h or TOE excludes thrombus.
• If AF >48h: anticoagulate ≥4 weeks before and ≥4 weeks after elective cardioversion.
• Drug choices:
  • Amiodarone: use in LV dysfunction or structural heart disease.
  • Flecainide: use if LV normal, no IHD.
  • DC shock: if urgent or drugs fail.

📚 Reference

• NHS Tayside AF Guidance

Fast Atrial Fibrillation and Rate Control

Related Subjects: |AF - General |AF and Anticoagulation |AF and Rate Control |AF and Rhythm Control and Cardioversion |AF ECG |DC cardioversion

⚡ Introduction

• Fast atrial fibrillation (AF) causes inefficient cardiac output and may worsen heart failure, angina, or exercise intolerance.
• Ventricular rates > 160/min are often poorly tolerated but depends on various factors.
• Many older tolerate rates up to ~160/min unless severe LV dysfunction or valvular disease is present. Slowly lower it.
• Drugs take time to act so set goals e.g. < 120/min in 1-2 hour if BP ok
• Management differs between acutely unwell patients and long-term outpatient care.

🚑 Acute AF Rate Control

• Always search for triggers: infection, dehydration, metabolic disturbance, PE, alcohol, or worsening pulmonary oedema.
• Correct K⁺/Mg²⁺, treat precipitants, oxygen only if hypoxic. Consider treating sepsis, dehydration, ACS, PE, thyrotoxicosis
• Haemodynamic compromise (shock, angina, pulmonary oedema, hypotension):
  • ➡️ Immediate DC cardioversion 120–200 J biphasic → 200 J (can be done without prior anticoagulation if emergency, but give treatment-dose LMWH) [NICE, 2014].
• Drug therapy:
  • Beta-blocker: Consider Bisoprolol 2.5 mg PO stat if comfortable and stable and BP > 100 mmHg. If BP less than 100 mmHg give Metoprolol 1 mg IV (repeat to max 10 mg) to reduce HR to 100-120/min. Avoid in asthma, acute pulmonary oedema, severe bradycardia.
  • Amiodarone: 150–300 mg slow IV over 30 min (large vein/central line), alternative if beta blockers not available or contraindicated then 900 mg/24h infusion. Ensure vein is flushed.
  • Digoxin: 500 micrograms PO, repeat 500 micrograms after 8h, then 125 micrograms OD. Best for patients with CCF or sedentary lifestyle. Dose adjust in elderly or renal impairment.
  • Special case: Suspected pre-excited AF (very fast, irregular, broad complexes) → avoid AV-nodal blockers; seek senior help/consider urgent cardioversion or consider Procainamide 10–15 mg/kg IV over 30–60 min.
• Anticoagulation: Start LMWH or a DOAC unless contraindicated.

📆 Long-Term Rate Control

• Bisoprolol: 2.5–5 mg PO OD. First-line. Avoid in asthma or decompensated heart failure.
• Verapamil: 40–120 mg PO TDS. Alternative if beta-blockers not tolerated. ❌ Never combine with beta-blockers (risk of complete heart block).
• Digoxin: Load (500 micrograms stat, then 250 micrograms 6–8h later), then maintain 125 micrograms OD.
  • Good in elderly or sedentary patients with CCF.
  • Lower dose if low body mass or renal impairment.
• Amiodarone: Only if no alternatives (significant long-term toxicity).
  • Loading: 200 mg TDS for 1 week → 200 mg BD for 1 week → 200 mg OD maintenance.
  • Counsel re: thyroid, liver, and pulmonary side effects.

🔑 Clinical Pearls

• Always consider anticoagulation (CHA₂DS₂-VASc and HAS-BLED assessment).
• Acute rate control is not just about drugs - treat the underlying precipitant.
• Long-term: aim for resting HR < 110/min (lenient control, RACE II trial) unless symptomatic.
• Digoxin alone is not adequate for active patients as it only slows resting HR.
• Amiodarone is for rhythm control rescue, not first-line long-term rate control.