AF

Question 1

AF

Answer 1

most common sustained cardiac arrhythmia
loss of active ventricular filling ass. w/:
stagnation of blood in atria–> thrombus formation and risk of embolism–> stroke
reduced cardiac output (esp during exercise) which may lead to HF

Question 2

epidemiology

Answer 2

3% of adults >20yo
greatest prevalence in:
older
HTN
HF
coronary artery disease
valvular heart disease
obesity
DM
CKD
more common in males than females

Question 3

aetiology

Answer 3

no obvious cause an all investigations normal in 11%

most common causes are coronary heart disease, HTN, valvular heart disease and hyperthyroidism

Question 4

risk factors

Answer 4

coronary artery disease
HTN
valvular heart disease
hyperthyroidism
rheumatic heart disease, heart failure
drugs
acute infection
electrolyte depletion
lung Ca
PE
DM
caffeine
alcohol 
obesity

Question 5

presentation

Answer 5

dyspnoea
palpitations
syncope
dizziness
chest discomfort 
stroke/TIA

Question 6

DDx

Answer 6

atrial flutter
atrial extrasystoles
supraventricular tachyarrhythmias
wolff-parkinson-white syndrome (commonest ventricular pre-excitement syndrome, palpitations, light headedness or syncope)
ventricular tachycardia

Question 7

associated diseases

Answer 7

other arrhythmias, eg SVT, atrial flutter
in wolff-parkinson-white can lead to rapid ventricular rates and ventricular fibrillation, esp when atrioventricular nodal blocking agents are used

Question 8

investigations

Answer 8

ECG
24h ambulatory ECG
blood tests: TFTs, FBC (anaemia may precipitate HF), U&E (abnormal serum K levels can lead to AF), LFTs, coag screen (pre-warfarin)
CXR
echo
CT/MRI head if indication of stroke/TIA

Question 9

management

Answer 9

control arrhythmia and thromboprophylaxis
rate control:
B-blocker
rate limiting CCB
digoxin
do not offer amiodarone for long term rate control

rhythm control:
cardioversion
amiodarone
B-blockers

Question 10

left atrial ablation

Answer 10

if drug treatment has failed, or is unsuitable
left atrial catheter ablation for paroxysmal AR
consider in persistent AF

Question 11

anticoagulation

Answer 11

apixaban
vitamin K antagonist (eg warfarin)
if ineffective consider alternative anti-stroke strategies
do not offer aspirin monotherapy solely to reduce risk if stroke in AF

Question 12

complications

Answer 12

increased risk of:
stroke
acute HF
cardiomyopathy
premature death

Question 13

prognosis

Answer 13

reduced life expectancy in older patients

double mortality, 5-fold increase in stroke risk

Question 14

prevention

Answer 14

smoking cessation
alcohol moderation or avoidance
diet - caffeine may induce paroxysmal AF in susceptible patients