Atrial Fibrillation

Question 1

How is AF characterised?

Answer 1

rapid, chaotic, uncoordinated and ineffective atrial activation

Question 2

What is the atrial rate?

Answer 2

400-600 bpm

Question 3

What is the ventricular rate?

Answer 3

80-180 bpm

Question 4

What diseases is AF common in?

Answer 4

CHD
hyperthyroidism
rheumatic heard disease
mitral valve disease
CHF

Question 5

Presentations of AF

Answer 5

irregular pulse
ECG changes
palpitations
dyspnoea (SOB)
fatigue
tight chest/pain
dizziness, light-headed, syncope
disordered sleep

Question 6

What ECG changes occur?

Answer 6

irregular R-R interval
elevated HR
absence/loss of P waves
F waves (fibrillatory) - irregular atrial activations/chaotic isoelectric line

Question 7

What are the 5 classifications of AF?

Answer 7

1 first detected or diagnosed AF
2 paroxysmal AF
3 persistent AF
4 long-standing persistent AF
5 permanent AF

Question 8

What is first detected/diagnosed AF?

Answer 8

first clinical presentation
patient still in AF
independent of duration and other symptoms

Question 9

Paroxysmal AF?

Answer 9

recurrent
self-terminating episodes
lasting less then 7 days

Question 10

Persistent AF?

Answer 10

episodes lasting longer then 7 days

need termination by pharmacological or electrical cardioversion

Question 11

Long standing persistent AF?

Answer 11

episodes lasting longer then 1 year when decision made for rhythm control

Question 12

Permanent AF?

Answer 12

episodes lasting more then 1 year
decision not to pursue restoration of sinus rhythm
accepted

Question 13

Underlying mechanisms of AF?

Answer 13

enhanced automaticity
multiple re-entrant circuits
atrial remodeling

Question 14

What type of remodeling occurs?

Answer 14

electrical
cellular
structural
neurohormonal

Question 15

What does remodeling lead to?

Answer 15

initiation, progression and maintenance of AF

Question 16

Where is a common site of clot formation?

Answer 16

left atrial appendage

Question 17

How can AF cause stroke?

Answer 17

blood pools in atria
blood clot forms
whole/part of the clot breaks off
blood clot travels to brain and blocks cerebral artery causing stroke

Question 18

4 parts of treatment approach

Answer 18

control ventricular rate - rate control
control sinus rhythm - rhythm control
prevent recurrent episodes
prevent stroke (thromboembolism)

Question 19

What does thromboprophylaxis mean?

Answer 19

prevention of thromboembolic consequences (stroke)

Question 20

How to assess stroke risk?

Answer 20

CHA2DS2 VASc

Question 21

How to assess bleeding risk?

Answer 21

HAS BLED

Question 22

What therapy is given for stroke prevention?

Answer 22

anticoagulant

Question 23

2 types of anticoagulants that can be given

Answer 23

vitamin K antagonist OACs - warfarin

novel, new or non-vit K antagonists OACs (NOACs)

Question 24

2 types of NOACs

Answer 24

direct thrombin inhibitor - dabigatran

direct factor Xa inhibitor - rivaroxaban, apixaban, edoxaban

Question 25

How to restore sinus rhythm?

Answer 25

electrical cardioversion - DC cardioversion | pharmacological cardioversion - amiodarone, flecainide, propafenone

Question 26

When is electrical cardioversion used?

Answer 26

if there's hemodynamic instability

Question 27

When is amiodarone given?

Answer 27

no hemodynamic instability | but structural heard disease

Question 28

Pharmacological therapy for rhythm control

Answer 28

beta blocker amiodarone, dronedarone flecainide, propafenone

Question 29

non-pharmacological therapy for rhythm control

Answer 29

``` left atrial catheter ablation ( radiofrequency/cryoenergy to isolate vein/foci) surgical ablation (COX-Maze procedure) ```

Question 30

What is rate control used for?

Answer 30

control or slow the fast ventricular response via AV blockade

Question 31

What is rate control used for in paroxysmal and persistent AF?

Answer 31

control of ventricular rate

Question 32

What is rate control used for in permanent AF?

Answer 32

long term rate control

Question 33

What pharmacological therapy is used for rhythm control?

Answer 33

``` beta blockers (not sotalol) Ca channel blocker (diltiazem, verapamil) digoxin ```

Question 34

Non-pharmacological therapy in rate control

Answer 34

AV node ablation with pacing