Cardiology
Atrial Fibrillation
심방세동
Irregular atrial electrical activity; increases stroke risk 5-fold
- How common
- 5% in 60s, 10% in 80s
- Typical age
- Increases after age 60
What is it?
Ectopic foci near pulmonary vein ostia trigger reentry → chaotic atrial activity → irregular ventricular response → LA stasis → thrombus → embolic stroke.
Commonly affected: Atria, LA appendage, brain (embolic)
How it develops
- PV triggerIncreased automaticity at PV ostia
- Atrial reentryStructural/electrical remodeling
- Irregular ventricular responseIrregular AV node conduction
- LA thrombus/strokeLA appendage stasis
Symptoms
- Stroke (complication)Devastating complication
- PalpitationsAwareness of irregular heartbeat
- DizzinessReduced cardiac output
- DyspneaWith concurrent HF
- FatigueReduced cardiac output
How it is examined
- Pulse examIrregularly irregular, often rapid
- ECG (essential)No P waves, irregular RR, fibrillatory waves
- CHA2DS2-VASc scoreStroke risk stratification
Imaging
CXR for HF/underlying disease.
- Possible LA enlargement
TEE to rule out LA appendage thrombus (before cardioversion/ablation).
- LA enlargement
- LAA thrombus (possible)
Non-surgical care
- Rate controlBeta-blocker, CCB (diltiazem), digoxin
- Rhythm control (selective)Amiodarone, flecainide (selected patients)
- Anticoagulation (CHA2DS2-VASc based)DOAC (apixaban, rivaroxaban) or warfarin
- Electrical cardioversionFor instability or severe symptoms
Conservative options are generally tried first. Medications listed here can have side effects — discuss them with your prescriber.
When surgery is considered
Failed medical therapy or severe symptoms
Procedures that may be discussed
- Pulmonary vein isolation (catheter ablation)
- Maze procedure (concomitant with heart surgery)
- LA appendage occlusion (Watchman, if anticoag contraindicated)
Outlook
Anticoagulation reduces stroke risk 60-70%; ablation success rate 70-80%.