Atrial fibrillation

Question 1

What are the risk factors for developing AF?

Answer 1

CARDIAC FACTORS:
Hypertension
Ischemic heart disease
Structural heart diseases e.g. heart defects

NON-CARDIAC:
Diabetes
Thyrotoxicosis
Alcohol intake
COPD

Question 2

What sort of arrhythmia is atrial fibrillation?

Answer 2

A supraventricular tachycardia

Question 3

What is the value of increased stroke risk associated with AF?

Answer 3

The risk of having a stroke is 5 times mote likely in AF patients

Question 4

What is the pathophysiology of AF?

Answer 4

AF happens when the electrical impulses in the atria fire chaotically when they should be steady and regular- this sows as ‘quivering’ on an ECG trace
- can cause an irregular, rapid atrial rate of 300-600 bpm
- ventricular rate of 100-180 bpm

Question 5

What is the difference between acute and chronic AF?

Answer 5

• Acute: Onset within the last 48 hours- very difficult to diagnose
• Chronic- onset that has been greater than 48 hours. This is most cases of AF

Question 6

What are the three types of AF in terms of response to treatment?

Answer 6

• Paroxysmal- intermittent, self-limiting AF
• Persistent- AF that is successfully converted by treatment
• Permanent- AF that has failed to respond to treatment

Question 7

What is the ventricular rate in AF?

Answer 7

Between 100-180bpm

Question 8

What gender is more common to have AF?

Answer 8

More common in men BUT women respond worse to treatment

Question 9

What would an ECG trace in AF look like?

Answer 9

There is no P wave- the p wave usually represents the coordination of atria- but in AF this isn’t happening in a coordinated way
- shows fibrillation waves

Question 10

Symptoms of AF

Answer 10

Can be asymptomatic!
Common:
SOB
Dizziness
Fatigue
Palpitations

Complication:
(Often how af is detected)
Heart failure
angina
thromboembolism

Question 11

What are the three areas of managing AF according to the NICE 2021 guidance?

Answer 11

Stroke prevention
Rate control- 1st line
Rhythm control- if rate is insufficient

Question 12

How is stroke risk assessed in af patients?

Answer 12

CHA2-DS2-VASc score:
If score is >1 in men and >2 in women, consider anticoagulation

Also need to assess bleeding risk- using the ORBIT score

Question 13

What is the first line choice for anti-coagulation in AF?

Answer 13

The DOACs:
Apixaban
Rivaroxaban
Dabigatran
Edoxaban

• if DOAC not tolerated- warfarin

Question 14

What is a left atrial appendage occlusion?

Answer 14

The formation of clots in a small sac in the muscle wall of the left atrium - this is where most AF caused clots appear

Question 15

What is the alternative to anti-coagulation for stroke prevention if DOACs/Warfarin is inappropriate?

Answer 15

Surgical procedure to seal off the left atrial appendage (sac in left atria where most AF-related clots form)- uses a watchman device- a self-expanding device that blocks off the entry of blood to the LAA to prevent clots forming here.

Question 16

What is the recommended treatment for rate control in AF?

Answer 16

Slowing the HR
- is 1st line srategy!

Standard beta-blocker OR rate-limiting calcium channel blocker e.g. Diltiazem or verapamil

Digoxin- only if have a sedentary lifestyle as dioxin doesn’t not help exercise-induced increase in HR/AF

If monotherapy is insufficient,
Combine 2 of these drugs e.g. Beta blocker + CCB ( has to be diltiazem as verapamil is not recommended for combo use)
Or add digoxin

Question 17

What are examples of rate-limiting CCBs?

Answer 17

Diltiazem
Verapamil

Question 18

Which of the two rate-limiting CCBs can be used in combo therapy with a beta-blocker?

Answer 18

Diltiazem

Verapamil- not recommended for combination use

Question 19

What is the recommended treatment for rhythm control in AF?

Answer 19

When rate control is unsuccessful, inappropriate or patient is still symptomatic:

1st line = electrical cardioversion (see arrythmias)
2nd line =
- Standard beta-blocker (has rate and rhythm properties)
- Dronedarone
- Amiodarone (2nd to dronederone as it can make HF worse- Cid in HF)

Question 20

When is rate control NOT the recommended first line treatment for AF?

Answer 20

• If it caused by a reversible cause e.g. infection- treat the infection first
• If got heart failure caused by af: b-blockers used in af can worsen hf initially
• If new onset of af (within last 48hrs) = non-pharmacological management is first line

Question 21

What is the ‘Pill in the pocket’ strategy of treating AF?

Answer 21

Patient carries drug with them and uses only in the cafe of an AF attack
DRUG = Flecainide
- However, if attacks become frequent, patient should be changed to conventional rate/rhythm strategies