AF

Question 1

What is atrial fibrillation?

Answer 1

Most common type of arrhythmia due disorganised electrical signalling causing atria to fibrillate i.e. muscle not fulling contracting but contracting irregularly at fast pace
=atria ejection decreases and blood pools in the atria

Question 2

What are common causes of AF?

Answer 2

Changes which occur due to ageing process 
Heart failure 
Hypertension 
IHD
PE
Mitral valve disease 
Pneumonia 
Hyperthyroidism 
Caffeine 
Alcohol 

I.e. all can cause structure changes/fibrosis to atria and can alter electrical signalling which can perpetuate the AF

Question 3

What symptoms would you expect someone with AF to present with?

Answer 3

Palpitations 
Indications of inadequate BF:
-Chest pain 
-Dyspnoea
-Faintness

Question 4

What signs would you expect to see in patient with AF?

Answer 4

Irregularly irregular pulse
Haematologically unstable
I.e. tachycardia and drop in BP
Possibly signs of LVF i.e. pulmonary oedema etc

Question 5

What features on an ECG would indicate AF?

Answer 5

Tachycardia on rhythm strip

Dissociated between P waves and QRS complexes i.e. irregularly irregular rhythm

F waves

Question 6

A person with AF presents to AE with chest pain, syncope and signs of shock, how should they be managed acutely?

Answer 6

Airway 
Breathing 
Circulation 
Disability 
Exposure 

Cardioversion to shock back into rhythm

Question 7

What are the main goals of management of chronic AF?

Answer 7

Rate control
Rhythm control
Anticoagulation

Question 8

When is it appropriate to control rhythm as well as rate in AF patients? How can rhythm be controlled?

Answer 8

Young patients
Symptomatic patients
When presenting with AF for first time

Electrically = DC cardioversion

Chemically= Anti arrhythmics i.e. amiodarone/flecainide

Question 9

What medications are used for rate control in AF? How does this differ for elderly people and why?

Answer 9

Beta-blockers

• Bisoprolol
• Metoprolol
• Atenolol

Rating limiting Ca2+ channel blockers i.e. Verapamil/Diltiazem

Digoxin used instead of bisoprolol due to b-blocker causing drop in BP which can lead to vasovagal event. Digoxin doesn’t drop BP so indicated in elderly people

Question 10

What is paroxysmal AF? What is used to detect it and how can it be treated?

Answer 10

AF presents rapidly and severely but disappears within 7 days

“Pill in the pocket”
Sotalol
Flecainide = Na+ channel blockers

Question 11

Why are anticoagulants required for people with AF?

Answer 11

Decreased atrial ejection leads to blood stasis which leads to increased risk of thrombus forming which can increase the risk of stroke or MI

Question 12

Which anticoagulant are used for acute AF? What are the specific indications for each?

Answer 12

Heparin= until full risk assessment of emboli made

Apixaban/Rivaroxiban (DOAC) or warfarin= px at high risk of emboli

Question 13

What needs to be done before anticoagulants prescribes in chronic AF? What is the anticoagulation management in chronic AF?

Answer 13

Need assess risk vs benefits of given anti-coagulants used the CHAD2S2 VASc score and HAS BLED score

DOACs = rivaroxiban or apixaban
Warfarin

Question 14

What are the possible complications of someone with AF?

Answer 14

Stroke
MI
Heart failure

Question 15

What can AF lead to exacerbation of HF?

Answer 15

Loss of atrial ejection leads to decreased SV due to decreased filling of ventricles

Build of blood in atria can lead to back pressure which leads to exacerbation of LVF

Question 16

Where is the a clot associated with AF most likely to form? Why?

Answer 16

Left atrial appendage
- doesn’t have uniform concentric contraction which leads to blood stasis= induces hypercoagulable state and precipitates the formation of clots

Question 17

Why might someone with AF complain of loss of vision?

Answer 17

AF can cause a retinal infarct where a clot formed due to AF blocks the vessels supplying the retina which leads to reduced blood flow to the retina and the consequent loss or changes to vision

Question 18

When is digoxin useful in managment AF?

Answer 18

in elderly people
-doesn’t drop the blood pressure like beta-blockers do so doesn’t add to risk of vasovagal risk in elderly

In patients concommital HF
-Digoxin is ionotropic and chronotripic i.e. cause the heart to contract better which can help with the decreased CO state in HF

Question 19

What is the time frame which cardioversion can be used in AF patients for rhythm control?

Answer 19

Only <12hrs since 1st presentation of AF

-due to risk of stroke i.e. 1st presentation means that patient will not be on anticoagulants