⚡ Atrial Fibrillation = chaotic atrial activation → loss of effective atrial contraction. 🫀 Leads to ↑ risk of stroke, heart failure, and reduced cardiac output. 💡 Most common sustained arrhythmia in adults, prevalence ↑ with age.

💓 Management of Acute AF (Ventricular Rate >130 bpm)
1️⃣ Assess stability: SBP, chest pain, pulmonary oedema. If unstable → urgent DC cardioversion. 2️⃣ Oxygen, IV access, continuous monitoring. Correct electrolytes (K+, Mg2+, Ca2+). 3️⃣ IV antiarrhythmics while awaiting DC cardioversion: Amiodarone 150 mg over 10 min, then 1 mg/min infusion. 4️⃣ Consider anticoagulation as soon as safe (UFH or LMWH bridging if AF duration uncertain). 5️⃣Identify and treat underlying cause (infection, ACS, thyrotoxicosis, alcohol, HF).

💓 Management of Acute AF (Ventricular Rate >130 bpm)

1️⃣ Assess stability: SBP, chest pain, pulmonary oedema. If unstable → urgent DC cardioversion.
2️⃣ Oxygen, IV access, continuous monitoring. Correct electrolytes (K+, Mg2+, Ca2+).
3️⃣ IV antiarrhythmics while awaiting DC cardioversion: Amiodarone 150 mg over 10 min, then 1 mg/min infusion.
4️⃣ Consider anticoagulation as soon as safe (UFH or LMWH bridging if AF duration uncertain).
5️⃣Identify and treat underlying cause (infection, ACS, thyrotoxicosis, alcohol, HF).

📖 Pathophysiology

Disorganised atrial electrical activity → multiple re-entry circuits 🧠
Ventricular response depends on AV node conduction ⏱️
Valvular AF (mitral stenosis or mechanical valves) → high thromboembolic risk 🏥
Non-valvular AF → stroke risk assessed using CHA₂DS₂-VASc 🧮
AF types: paroxysmal, persistent, long-standing persistent, permanent ♾️
Rapid ventricular rates → ↓ diastolic filling → hypotension, pulmonary congestion

🧬 Aetiology

Cause	Mechanism	Notes
Hypertension	LVH → atrial stretch → fibrosis	Most common in older adults
Ischaemic Heart Disease	Myocardial scar → re-entry circuits	May coexist with HF
Valvular Disease	Mitral stenosis/regurgitation → LA enlargement	High embolic risk
Heart Failure (HFrEF/HFpEF)	Atrial stretch, neurohormonal activation	Rate control may be difficult
Thyrotoxicosis	↑ automaticity	Reversible if treated
Alcohol (“holiday heart”)	Triggered AF episodes	Often paroxysmal
Post-surgery	Inflammation, electrolyte shifts	Common after cardiac surgery
Genetic / idiopathic	Ion channel or structural variants	Rare, younger patients

📊 Types of AF

Type	Definition
Paroxysmal ⏳	<48h (up to 7 days), may terminate spontaneously
Persistent ⏱️	>7 days or requires cardioversion
Long-standing Persistent 📆	>12 months duration
Permanent ♾️	Accepted by patient & clinician, no further rhythm control attempts

🩺 Clinical Presentation

Palpitations, irregular pulse ✨
Dyspnoea 🫁, fatigue, exercise intolerance
Chest discomfort or angina 💔
Syncope or presyncope 💫
Stroke or TIA (often first presentation) ⚡
May be asymptomatic in elderly patients 👴👵

⚠️ Clinical Effects

Stroke / systemic embolism (risk ↑ in valvular AF) 🛡️
Heart failure / pulmonary oedema 🫁
Reduced cardiac output, exercise intolerance ⚡
Increased hospitalisations & mortality 📈

🔬 Investigations

Investigation	Purpose	Notes
ECG	Confirm AF, assess ventricular rate	Absent P waves, irregularly irregular rhythm
Bloods	Screen for triggers	FBC, U&E, electrolytes, Mg, Ca, TFTs, LFTs, renal function, alcohol, iron studies
Echocardiography	Assess LV function, LA size, valvular disease	Transthoracic first; TOE if thrombus suspected
Thyroid function tests	Identify thyrotoxicosis	Correctable cause of AF
Chest X-ray	Check cardiac size, pulmonary congestion	May reveal underlying HF
TOE	Identify LA appendage thrombus	Prior to cardioversion if >48h AF duration
Ambulatory monitoring	Paroxysmal AF detection	Holter 24-48h or event monitor

🎯 Rate Control

Target: <80 bpm at rest symptomatic; <110 bpm asymptomatic 🏃‍♂️
First-line: β-blockers (bisoprolol, metoprolol) 💊
CCB (diltiazem, verapamil) if β-blocker not tolerated (caution HF) ⚠️
Digoxin: for sedentary or HF patients, often in combination 💊
Monitor HR, BP, renal function 📊

🔄 Rhythm Control

Consider in younger, symptomatic, or newly diagnosed patients 💡
Class Ic antiarrhythmics (flecainide, propafenone) if no structural disease 🏥
Class III (amiodarone, sotalol, dronedarone) if structural heart disease
Electrical cardioversion (DCCV) under sedation ⚡
Catheter ablation: for recurrent or refractory AF 🔧
Monitor QT interval if using class III agents 🧬

🛡️ Anticoagulation

Type	Indications	Notes
Warfarin	Valvular AF, high stroke risk (CHA₂DS₂-VASc)	INR 2–3, monitor regularly 📈
DOACs	Non-valvular AF, CHA₂DS₂-VASc ≥2 men / ≥3 women	Apixaban, rivaroxaban, dabigatran, edoxaban 💊
LMWH bridging	Before cardioversion if not anticoagulated	Short-term therapy only ⏳
Left atrial appendage occlusion	Contraindication to anticoagulation	Devices like Watchman 🛠️

🚨 Acute / Fast AF Management

Scenario	Management	Notes
Unstable AF (SBP<90, chest pain, pulmonary oedema)	Urgent DC cardioversion 💥, IV amiodarone if needed	Anticoagulate ASAP; monitor oxygen & electrolytes 🫁
Rapid AF >130 bpm, stable	Rate control: β-blockers, diltiazem, digoxin	Treat underlying causes (infection, thyrotoxicosis, HF) ⚡
Acute decompensated HF	Cautious rate control, oxygen, IV diuretics	Avoid verapamil/diltiazem in HFrEF ❌
New-onset AF <48h	Consider electrical cardioversion or pharmacologic (flecainide/amiodarone)	Assess anticoagulation based on risk ⚖️

🎛️ Rate Control

Target HR: <110 bpm (asymptomatic), <80 bpm (symptomatic).
First-line: β-blockers (bisoprolol, metoprolol).
Alternative: Non-dihydropyridine CCBs (diltiazem, verapamil) – avoid in HFrEF.
Digoxin: useful in sedentary patients or HF, often in combination.
Monitor HR, BP, renal function.

🔄 Rhythm Control

Consider for symptomatic, younger patients, or failed rate control.
Antiarrhythmics: Class Ic (flecainide, propafenone) if no structural heart disease; Class III (amiodarone, sotalol) if structural disease.
Electrical cardioversion (DCCV) under sedation.
Catheter ablation for refractory or recurrent AF.
Monitor ECG, QT interval, electrolytes, liver function if on amiodarone.

🛡️ Anticoagulation

All AF patients: assess stroke risk (CHA₂DS₂-VASc).
Valvular AF (mechanical valves or mitral stenosis) → warfarin INR 2–3.
Non-valvular AF → DOACs preferred (apixaban, rivaroxaban, dabigatran, edoxaban).
Bridge therapy with LMWH if initiating warfarin pre-cardioversion.
Avoid aspirin monotherapy (ineffective for stroke prevention).

🧾 Investigations / Monitoring

ECG: confirm type of AF and ventricular response.
Echo: LV function, LA size, valvular disease.
TOE: detect LA appendage thrombus if cardioversion delayed.
Bloods: renal function, electrolytes, TFTs, FBC.
Holter / ambulatory ECG for paroxysmal AF.
Monitor anticoagulation: INR (warfarin), renal function (DOACs).

💊 Managing Underlying Conditions

Hypertension control (ACEi, ARB, diuretics as indicated).
Heart failure optimization.
Sleep apnea diagnosis and CPAP therapy.
Thyroid disease management.

🌱 Lifestyle Modifications

Weight reduction (BMI <25 kg/m²).
Moderate exercise; avoid excessive high-intensity exertion.
Limit alcohol and caffeine intake.
Smoking cessation.

👴 Special Populations

Elderly: rate control + anticoagulation preferred; rhythm control if symptomatic and feasible.
Pregnancy: prefer heparin; avoid warfarin first trimester.
LA appendage occlusion (Watchman) if anticoagulation contraindicated.

📈 Risk Stratification

Score	Components	Notes
CHA₂DS₂-VASc	CHF, HTN, Age ≥75(2), DM, Stroke/TIA(2), Vascular disease, Age 65-74, Sex (female)	Guides anticoagulation 🛡️
HAS-BLED	HTN, Abnormal renal/liver, Stroke, Bleeding, Labile INR, Elderly, Drugs/alcohol	Assess bleeding risk ⚠️

🌱 Lifestyle & Comorbidities

🏃 Moderate exercise; avoid excess high-intensity
🍷 Limit alcohol; avoid binge drinking
☕ Avoid stimulants: caffeine, nicotine, recreational drugs
🚭 Smoking cessation
📉 Control BP and optimise HF therapy
🛠️ Weight reduction, treat OSA, diabetes management

🩺 Case Examples

Case 1 - Symptomatic AF: 72yo male, palpitations, pulse 140 bpm. Rate control with β-blocker or digoxin. Anticoagulate as per CHA₂DS₂-VASc. ❌ Avoid class Ic if structural disease.
Case 2 - Incidental AF: 65yo female, asymptomatic, pulse 80 bpm. Anticoagulate if CHA₂DS₂-VASc ≥2. Observation if stable. ❌ Avoid aspirin monotherapy.
Case 3 - Acute Decompensation: 80yo male, pulmonary oedema, AF 160 bpm, hypotensive. Urgent stabilisation, IV diuretics, cautious rate control, DC cardioversion if needed, anticoagulate once safe. ❌ Avoid verapamil/diltiazem in HFrEF.

📚 References

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💓Atrial Fibrillation (AF)✅

📖 Pathophysiology

🧬 Aetiology

📊 Types of AF

🩺 Clinical Presentation

⚠️ Clinical Effects

🔬 Investigations

🎯 Rate Control

🔄 Rhythm Control

🛡️ Anticoagulation

🚨 Acute / Fast AF Management

🎛️ Rate Control

🔄 Rhythm Control

🛡️ Anticoagulation

🧾 Investigations / Monitoring

💊 Managing Underlying Conditions

🌱 Lifestyle Modifications

👴 Special Populations

📈 Risk Stratification

🌱 Lifestyle & Comorbidities

🩺 Case Examples

📚 References

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