MP323 - AF Flashcards
what is atrial fibrillation
supraventricular tachycardia characterised by disorganised atrial electrical activity
symptoms of AF
- breathlessness/difficulty breathing
- dizziness/lightheaded/feeling faint
- palpitations
- tiredness/weakness
- chest discomfort
- difficulty exercising
clinical tests to diagnose AF
ECG
holter monitor
loop recorder
echo
potential differential diagnosis
diabetes
hyperthyroidism
anaemia
renal function
infections
high cholesterol
management of AF
- alleviate symptoms
- manage complications to irregular heart rate
- reduce risk of embolic stroke
- reduce risk of HF/LVSD
CHA2DS2-VASc score risk factors
chronic heart failure
hypertension
age (>65 or >75 (2 points))
diabetes
stroke/TIA (2 points)
VA vascular diseases (IHD/PAD)
sex (female)
treatment options against clots
warfarin - vitamin K antagonist
DOAC
factor Xa inhibitor
direct thrombin inhibitor
alleviate symptoms - rate control
- control the ventricular rate using AV blocking drug
- choice of AV blocking drug is based on left ventricular systolic function
AV blocking drugs
rate-limiting BBs
non-dihydropyridine CCBs (verapamil)
digoxin
alleviate symptoms - rhythm control drugs
class III (amiodarone)
class IV (flecainide)
amiodarone as a drug
- acts by blocking potassium channels
- effective but toxicity is a concern
- half-life is 42 days
- inhibition of T4 and T3 entry into the peripheral tissue
- preferred in patients with LVSD
- chemical cardioversion
flecainide as a drug
- maintain sinus rhythm or chemical cardioversion
- significant coronary artery disease is contraindicated
- can be used as ‘pill-in-the-pocket’ approach