Atrial fibrillation Flashcards
What is AF?
Supraventricular tacharrhythmia characterised by ineffective, chaotic, irregular and rapid (300-600BPM) atrial activity -> deterioration of atrial mechanical function. Disorganised electrical activity
Irreguarly irregular rhythm
Risks for AF
Pirates
Pulmonary embolism
Ischaemia
Respiratory disease
Atrial enlargement or myxoma
Thyroid disease
Ethanol
Sepsis/sleep apnoea
Cardiac causes of AF
HPTN
IHD
HF
Sick sinus syndrome
Pericarditis
Infiltrative heart disease
Valvular HD - mitral
Cardiomyopathies
Myocarditis
Congenital HD
How to manage AF?
- Rate control
- Beta blockers, rate limiting CCBs, digoxin
- Rhythm control - DC eletrical cardioverison or amiodarone or flecainide
- Reduce clot risk - DOAC or warfarin
- Test clotting risk eg
- ORBIT scoring - replaced HASBLED ]
- CHA2DS2-Vasc scoring
- If chad higher than orbit offer anticoag
Atrial fibrillation on ECG
Irreguarly irregular pulse
No p waves
Paroxysmal vs persistent AF
Paroxysmal = over 30 s but under 7 days, self terminating and recurrent
Persistent = Episodes over 7 days
What is it called when AF fails to terminate?
Permanent AF
Terminated and relapses within 24 hours or long standing eg over a year
Rate control management in AF - when prefer over rhythm? What use?
BCD - over 65 or hx IHD
Beta blockers eg bisoprolol
Calcium channel blockers eg dilatezam
Digoxin
When is digoxin preferred in AF?
Co-existing HF or hypotension
When do you use rhythm control in AF?
Under 65 years, symptomatic, 1st presentation, lone AF or AF to a precipitant or CCF
What use in rhythm control for AF?
Chemical or electrical
Chemical = sotalol, Amiodarone, flecainide (in absence of structural HD)
Electrical - in acute scenario if patient is haemodynamically unstable ]or elective
How do you determine risk of stroke with AF?
CHADVASC score - need for anticoagulation vs HASBLED score - risk of bleeding with anticoagulants
What does the CHADVASC score consider?
Congestive cardiac failure
HTN
Age
Diabetees
Stroke or TIA prev = 2
Vascular disease
Sex - female = +1
How high does the CHADVASC score need to be to offer anticoagulation in AF?
> 2 or =
What does the HASBLED score consider?
HTN
Abnormal renal function or liver
Stroke or history of
Bleeding, history of or high risk of
Labile INRs (<60% therapeutic range)
Elderly
Drugs predisposing to bleeding, alcohol use
When is considered high risk of bleed with HASBLED score?
> 3 = high risk of bleeding
Non cardiac causes af
Sepsis
PE
Thyrotoxicosis
Lung or pleural disease
Chest trauma
Hypokalaemia
Hypovolaemia
Hypothermia
Alcohol abuse/drug abuse eg cocaine
Symptoms AF
Palpitations
Dyspnoea
Chest pain
Dizziness
Syncope
Fatigue
Signs AF
Irreguarly irregular pulse
Signs of HF
Complications AF
Stroke - 5x risk
HF
Tachycardia induced Cardiomyopathy + critical cardiac ischaemia
Bloods for AF
FBC
U+Es
TFTs
Magnesium
LFTas
Coag screen
Investigations AF
CXR - HF, mitral valve disease
ECG
ECHO - risk underlying structural/functional disease
CT/MRI brain - stroke/TIA suggestion
AF on ECG
No p waves - no synchronised depolarisation
Fibrillatory waves - no baseleine
F waves = flutter waves
Treatment for haemodynamically instability (hypotension, HF) in AF
Immediate elctric cardioversion
