AF

Question 1

What is atrial fibrillation?

Answer 1

Common type of supraventricular tachycardia characterised by uncoordinated atrial activation that results in an irregular ventricular response

Question 2

What is acute atrial fibrillation?

Answer 2

<48hrs

Question 3

What is paroxysmal atrial fibrillation? (2)

Answer 3

• If AF terminates spontaneously
• Terminates within 7 days (most commonly occurs within 24hrs)

Question 4

What is persistent atrial fibrillation?

Answer 4

Continues for >7 days but is amended with cardioversion

Question 5

What is permanent atrial fibrillation? Treatment?

Answer 5

Cannot achieve sinus rhythm - can not be cardioverted

Treatment:
- Rate control
- anticoagulation if appropriate

Question 6

List causes of atrial fibrillation (8)

Answer 6

• Ischaemic heart disease
• Heart failure
• PE
• Valve disease
• Hypertension
• Hyperthyroidism
• Pneumonia
• Alcohol

Question 7

Which group of people is atrial fibrillation very common in?

Answer 7

Elderly

Question 8

What is atrial flutter? on ECG?

Answer 8

Form of supraventricular tachycardia characterised by a succession of rapid atrial depolarisation

b) - Sawtooth pattern
- 2:1 of P waves to QRS complexes

Question 9

List clinical features of atrial fibrillation/flutter (5)

Answer 9

• Irregularly irregular pulse
• Palpitations
• Chest pain
• Dyspnoea
• Faintness

Question 10

How can fast AF present? (3)

Answer 10

• Heart failure (SOB)
• Pulmonary oedema
• Peripheral oedema

Question 11

What would you see on an atrial fibrillation ECG? (3)

Answer 11

• Absent P waves
• Irregular, small QRS complexes
• Irregularly irregular RR intervals

Question 12

What is a broad complex tachycardia? Cause?

Answer 12

100bpm+ and QRS is wider than 3 small squares on ECG (120ms)

Atrial fibrillation with bundle branch block is the most likely cause in a stable patient

Question 13

How should palpitations be investigated after initial bloods and ECG?

Answer 13

Holter monitor

Question 14

What do we do if dysrhythmia is confirmed from Holter monitoring

Answer 14

Consider investigations like an echocardiogram

Question 15

What if Holter monitor is normal and the patient continues to have symptoms?

Answer 15

External loop recorder should be considered (continuously monitor heart activity)

Question 16

Why would you do a transthoracic echocardiogram?

Answer 16

Rule out underlying cardiac structural disease like valvular disease

Question 17

Why would you do a TFT?

Answer 17

Check for hyperthyroidism

Question 18

Management of AF if patient is haemodynamically unstable (BP <90/60)?

Answer 18

Emergency DC cardioversion (an urgent, synchronised electrical shock delivered via a defibrillator to immediately convert unstable, rapid heart rhythms)

Question 19

What other signs would mean we need to do DC cardioversion? (3)

Answer 19

• Syncope
• Myocardial ischaemia
• Heart failure

Question 20

What do we do in haemodynamically stable patients with a clear reversible cause for AF?

Answer 20

Rhythm control → Low Molecular Weight Heparin then DC cardioversion or amiodarone/flecainide

Question 21

when do you control the rhythm over rate control

Answer 21

. haemodynamically stable patients with a clear reversible cause for AF
- Age <65
- First presentation of AF (new onset AF <48 hours)
- Symptomatic/heart failure
- Atrial flutter being considered for ablation

Question 22

what do we do for new AF <48hrs

Answer 22

. LMWH then DC cardioversion or chemical cardioversion (amiodarone or flecainide)

Drugs: - Flecainide or amiodarone if there’s no structural or ischaemic heart disease (have to do an echo to look for structural heart disease)
- Amiodarone if there’s structural heart disease

Question 23

What do we do if AF >48 hours?

Answer 23

. Rate control, but can also do long term rhythm control → anticoagulation should be given for at least 3 weeks prior to cardioversion

Question 24

what is an alternate strategy if patient is cardiovascularly unstable for AF for over 48hrs

Answer 24

Transoesophageal echocardiogram to exclude a left atrial appendage thrombus

if no thrombus then patient can be immediately heparinised and cardioverted

Question 25

What do we do if there’s a high risk of cardioversion failure e.g. previous failure or AF recurrence?

Answer 25

Give 4 weeks amiodarone or sotalol before electrical cardioversion . After electrical cardioversion, anticoagulation for 4 weeks

Question 26

what is amiodarone? side effects?

Answer 26

. Class III anti-arrhythmic medication- works by slowing down nerve impulses in the heart to stabilize its rhythm side effects: - Bradycardia - Hyper/hypothyroidism - Pulmonary fibrosis - liver fibrosis/pneumonitis - jaundice - taste disturbance - persistent slate grey skin discolouration - raised serum transaminases - nausea - constipation (particularly at the start of treatment)

Question 27

what is the first line treatment for rate control?

Answer 27

- Beta-blocker → bisoprolol (contradicted in asthmatics) OR - Rate-limiting CCB → Diltiazem or Verapamil

Question 28

Second line rate control?

Answer 28

Digoxin- used if patient is sedentary or other drugs are unsuitable

Question 29

What do we do if a patient has been on ≥48 hours rate control then is considered for long-term rhythm control?

Answer 29

Delay cardioversion until they’ve been maintained on therapeutic anticoagulations for minimum 3 weeks

Question 30

Why shouldn’t you use beta blocker and verapamil together?

Answer 30

Can lead to heart block

Question 31

Which anticoagulant could be prescribed and why?

Answer 31

- DOAC: - Apixaban - dabigatran - edoxaban - rivaroxaban b) Dont need to monitor INR as you do with warfarin

Question 32

what would you if DOACs are contraindicated?

Answer 32

Give warfarin

Question 33

How do you determine the most appropriate anticoagulant strategy?

Answer 33

CHA2DS2VASc score: - 0 → no treatment - 1 → consider anticoagulation in males, don’t in females - ≥2 → give anticoagulation RF that could be scored (all 1 except stroke) . CHF . Hypertension . Age >75 . Age 65-74 . DM . Stroke . Vascular disease . Sex Female

Question 34

What if the CHA2DS2VASc score suggests no need for anticoagulation?

Answer 34

Do an echo to exclude valvular heart disease

Question 35

What do we do before anticoagulating post-stroke in a patient with AF?

Answer 35

Exclude haemorrhage with CT head Anticoagulants: - Warfarin - Direct thrombin inhibitor e.g. dabigatran - Factor Xa inhibitor e.g. apixaban TIA: Start immediately after excluding haemorrhage Stroke: After 2 weeks - give antiplatelet therapy in meantime

Question 36

What is an ORBIT score?

Answer 36

Assesses bleeding risk in patient with AF who are being considered for anticoagulation five parameters of an ORBIT score: - Age 75+ years - Anaemia → Haemoglobin <130 g/L in males, <120 g/L in females - Bleeding history - Renal impairment → eGFR <60mL/min/1.73 m^2 - Treatment with an antiplatelet agent

Question 37

What do we do in patients not responding to meds?

Answer 37

Catheter ablation of faulty electrical pathways: - Radiofrequency - Cryotherapy Anticoagulation for 4 weeks before and after procedure: ablation controls rhythm but doesn’t reduce stroke risk ^ based on CHADVasc score- Score 0 = 2 months anticoagulation Score ≥1 = long term anticoagulation

Question 38

What are complications of catheter ablation

Answer 38

- cardiac tamponade - Stroke - Pulmonary vein stenosis

Question 39

When would you not need to give rate or rhythm control? (4)

Answer 39

If the patient has all of: - no symptoms - 60–100bpm - haemodynamically stable - AF is chronic

Question 40

How do we treat atrial flutter?

Answer 40

Radiofrequency ablation of tricuspid valve isthmus