AF

Question 1

what is AF?

Answer 1

Supraventricular tachyarrhythmia
*Irregular, disorganised electrical activity in the atria
*Rapid firing impulses disorganised atrial
depolarisation and ineffective atrial contractions
*AV node receives more electrical impulses than it can conduct irregular ventricular rhythm

Question 2

what is the ventricular rate of untreated AF?

Answer 2

160-180 beats per minute (usually slower in elderly)

Question 3

what can irregular atrial contractions result in?

Answer 3

blood stasis
clot formation

Question 4

what is paroxysmal AF?

Answer 4

Episodes lasting longer than 30 seconds but less than 7 days (often less than 48 hours) that are self-terminating and recurrent

Question 5

what is persistent AF?

Answer 5

Episodes lasting longer than 7 days
*Or less than 7 days but requiring cardioversion
*Spontaneous termination of the arrhythmia is unlikely to occur after
this time

Question 6

define permanent AF?

Answer 6

–Fails to terminate using cardioversion,
–Terminated but relapses within 24 hours,
–Longstanding AF (usually >1 year) in which cardioversion has not been
indicated or attempted (sometimes called accepted permanent AF)

Question 7

what are the common causes of AF?

Answer 7

Hypertension, ischaemic heart disease, myocardial infarction, valvular
heart disease and hyperthyroidism

Question 8

does prevalence rise with age?

Answer 8

At the age of 40, we all have a 1 in 4 life time risk of developing AF (The Framingham Heart Study)

Question 9

why does having AF matter?

Answer 9

*Stroke and thromboembolism risk
–x5 times higher in AF
*Heart Failure
*Tachycardia-induced cardiomyopathy and critical
cardiac ischemia
*Reduced quality of life
*Increased risk of mortality

Question 10

what are the main symptoms of AF?

Answer 10

–Breathlessness
–Palpitations
–Chest discomfort
–Syncope or dizziness
–Stroke or transient ischaemic attack

Question 11

how do you formulate a diagnosis of AF?

Answer 11

Manual pulse palpation to assess for irregular
pulse
*12 lead ECG
*24 hour ambulatory ECG if paroxysmal AF
suspected
*Echocardiography

Question 12

what are the possible differential diagnosis?

Answer 12

*Atrial flutter — characterized by saw-tooth pattern of regular
atrial activation on the ECG
*Atrial extrasystoles — common & may cause an irregular pulse
*Ventricular ectopic beats
*Sinus tachycardia — SR with more than 100 bpm
*Supraventricular tachycardias, including atrial tachycardia,
AVNRT tachycardia, and WPW
*Multifocal atrial tachycardia.

Question 13

what management would you do with a person presenting with AF?

Answer 13

Identify underlying cause
*Treat arrhythmia
*Assess stroke risk
*Assess bleeding risk
*Monitoring and follow up
*Counselling of condition and medication

Question 14

what are the two types of treatment regimes?

Answer 14

rate and rhythm control?

Question 15

what is rate control?

Answer 15

–First line unless suitable for rhythm control/ investigations for rhythm ongoing
–Beta blocker (not sotalol)
–Or rate limiting calcium channel blocker (diltiazem or verapamil)
–Digoxin monotherapy
*Consider if very little physical exercise or other options ruled out

Question 16

what is rhythm control? who should it be considered in?

Answer 16

New onset AF (<48 hours)
–Reversible cause (e.g. chest infection)
–HF caused/worsened by AF
–Atrial flutter suitable for ablation
–Clinician judgement of patient
–May take time to determine if suitable for rhythm- in interim give rate

Question 17

how should someone with acute AF be managed?

Answer 17

Consider either pharmacological or electrical cardioversion for new-onset AF who will be treated by rhythm control
anticoag
bleed risk

Question 18

what should you offer in cardioversion?

Answer 18

–Flecainide or amiodarone if there is no evidence of structural or ischaemic
heart disease or
amiodarone if there is evidence of structural heart disease.
–If >48 hrs (or uncertain) and long-term rhythm control, delay cardioversion
until maintained on therapeutic anticoagulation for a minimum of 3 weeks.
During this period offer rate control as appropriate

Question 19

how is rhythm control implemented?

Answer 19

Specialist management
–Initiated in secondary care but often continued in
primary care
*Electrical cardioversion
*Pharmacological cardioversion
–Amiodarone (revise monitoring, adverse effects and interactions)

Question 20

who are beta blockers avoided in?

Answer 20

Normally avoid in people with history of obstructive airways disease

Question 21

what dose of atenolol should be given?

Answer 21

–50-100mg daily
–Monitor HR and BP to titrate against response

Question 22

what are the adverse effects of BBs?

Answer 22

Bradycardia and hypotension
*Cold extremities
*Disturbed sleep and nightmares
–less likely with water soluble agents such as atenolol
*Sexual dysfunction
*Can cause hypoglycaemia or hyperglycaemia in patients +/-
diabetes.
*Mask signs of a hypoglycaemia
*Withdrawal effects
*Fatigue

Question 23

what CCBs are used?

Answer 23

Rate limiting CCB used in AF
–Diltiazem and verapamil
*Off label use of diltiazem

Question 24

what is the consequence of CCBs and statins?

Answer 24

Interaction with other medication
–Simvastatin capped at 20mg

Question 25

when should you avoid CCBs?

Answer 25

avoid in HF as depresses cardiac function and can exacerbate symptoms

Question 26

what are some side effects of CCBs?

Answer 26

Headache, dizziness, hypotension,
bradycardia (refer to BNF for additional)

Question 27

when is flecainide given?

Answer 27

Infrequent paroxysms and few symptoms induced by known precipitants (alcohol, caffeine)

Question 28

when should you assess stroke risk?

Answer 28

–Symptomatic or asymptomatic paroxysmal,
persistent or permanent atrial fibrillation
–Atrial flutter
–A continuing risk of arrhythmia recurrence after
cardioversion back to sinus rhythm or catheter
ablation.

Question 29

when should bleed risk be assessed?

Answer 29

1. Starting anticoagulation
2. Reviewing people taking anticoagulants

Question 30

how is bleed risk assessed?

Answer 30

ORBIT

Question 31

when should you offer anticoagulation in AF?

Answer 31

chadvasc score of 2+ and men of 1

Question 32

when is a DOAC contraindicated?

Answer 32

not tolerated or not suitable in people
with AF, offer a vitamin K antagonist

Question 33

when may anticoagulation treatment not be worth it?

Answer 33

if patient is at an increased risk of bleeds

Question 34

how should you give anticoagulation in acute AF?

Answer 34

Heparin at initial presentation and continue until appropriate anticoagulant started

Question 35

when can you offer oral anticoagulation in confirmed diagnosis of af?

Answer 35

*Stable sinus rhythm is not successfully restored within the same 48-hour
period after onset
*High risk of AF recurrence (history of failed cardioversion, structural heart
disease, prolonged AF (>12 months), or previous recurrences
*Based on CHADSc-VASc