Atrial Fibrillation

Question 1

What is the definition of Atrial fibrillation?

Answer 1

Disorganised electrical activity in the atria leads to irregular ventricular rhythm

Question 2

What are common causes of Atrial Fibrillation?

(6)

Answer 2

• S – Sepsis
• M – Mitral valve pathology (stenosis or regurgitation)
• I – Ischaemic heart disease
• T – Thyrotoxicosis
• H – Hypertension

Question 3

What is the paroxysmal AF?

Answer 3

2 or more episodes, self terminating lasting <48 hours

Question 4

Paroxysmal AF - Investigations

Answer 4

Patients with a normal ECG and suspected paroxysmal atrial fibrillation can have further investigations with:
* 24-hour ambulatory ECG (Holter monitor)
* Cardiac event recorder lasting 1-2 weeks

Question 5

Paroxysmal AF - Management

Answer 5

1. Flecainide - ‘Pill in pocket approach’
   Indication : infrequent episodes without structural heart disease
   * Pill taken when symptoms start

Question 6

Valvular AF : Definition

Answer 6

AF with
* Significant mitral stenosis
* Mechanical heart valve
Assumed that valvular pathology has led to AF

Question 7

Valvular AF : Management

Answer 7

Cardiologist referral

Question 8

What is the definition of persistent AF?

Answer 8

continuous AF, lasting for >7 days

Question 9

What are the symptoms of AF?

Answer 9

1. Palpitation
2. Dyspnoea
3. Chest pain
4. Syncope
5. Irregularly irregular pulse

Question 10

What are the ECG features of AF?

Answer 10

• Absent P waves
• Narrow QRS complex tachycardia
• Irregularly irregular ventricular rhythm

Question 11

What is the first line management of AF?

Answer 11

Rate control;
1. Beta blocker
or
Rate limiting calcium channel blocker
1. Combinition of non rate limiting CCB + Beta blocker

Question 12

What is the management of Heart failure with Atrial Fibrillation?

Answer 12

Digoxin

Question 13

What are the indications for rhythm control in AF?

(5)

Answer 13

1. Haemodynamic instability secondary to AF
2. AF with a reversible cause
3. Heart failure primarily caused by AF
4. New onset AF < 48 hours
5. Atrial flutter whose condition is considered suitable for ablation strategy

Question 14

What are the options for rhythm control?

Answer 14

Cardioversion
1. Immediate cardioversion if Sx onset < 48 hours
1. Electrical cardioversion
2. Chemical cardioversion
* Flecainide - no structural heart disease
* Amiodorone - structural heart disease

2. Delayed Cardioversion
   1. Electric cardioversion after 3 weeks of anticoagulation
   2. Long-term rhythm control using medications

• First-line : Beta blockers
• Second-line - Dronedarone
  -for maintaining normal rhythm where patients have had successful cardioversion
• Amiodarone is useful in patients with heart failure or left ventricular dysfunction

Question 15

What is the management of a patient who presents <48 hours and clinically stable?

Answer 15

• TOE and rhythm control (if suitable)
  Or
• Rate control

Question 16

What is the management of a patient who presents >48 hours and clinically stable?

Answer 16

1. Rate control
   or
2. If considered for rhythm control
   * 2. - 3 weeks minimum of anticoagulation prior to cardioversion

Question 17

What is the role of Flecainide in chemical cardioversion?

Answer 17

• Indication : paroxysmal AF
• Contraindication : cannot be used in patients with structural heart condition

Question 18

What is the role of Amiodorone in chemical cardioversion?

Answer 18

Indication : if coexisting HF

Question 19

Amiodorone : MOA

Answer 19

** Indication**
* class III antiarrhythmic agent
* used in the treatment of atrial, nodal and ventricular tachycardias.

MOA : blocking potassium channels which inhibits repolarisation and hence prolongs the action potential.

Question 20

What are the side effects of Amiodorone? (5)

Answer 20

1. Photosensitivity
2. Slate-grey pigmentation
3. Hepatoxicity
4. Hypo/Hyperthyroidism
5. Pulmonary fibrosis
6. Lengthening of the QT interval
7. p450 inhibitor
8. Thrombophlebitis at injection side

Question 21

Monitoring of Amiodorone

Answer 21

• TFT, LFT, U&E, CXR prior to treatment
• TFT, LFT every 6 months

Question 22

What is management of AF in a clinically unstable patient?

Answer 22

1. Cardioversion
   * ECHO to r/o thrombus
   * AF has just started and no options to cardiovert - give IV amiodorone

Question 23

What does CHADSVASC stand for?

Answer 23

1. C ongestive heart failure
2. Hypertension
3. Age > 75 years
   * 65 -74 years
4. Diabetes
5. Prior Stroke, TIA or Thromboembolism
6. Vascular disease - Ischaemic heart disease and Peripheral arterial disease
7. Sex (Female)

Question 24

What is the role of a CHADSVASC score?

(3)

Answer 24

• Score >1 in males or >2 in females suggests need for anticoagulation
• If CHASVASC suggests no need for anticoagulation - Transthoracic echo must be done to exclude valvular heart disease
• Valvular heart diease is an absolute indication for anticoagulation

Question 25

What does ORBIT stand for?

Answer 25

**O**lder age > 75 years **R **educed haemoglobin/anaemia (Hb <130 or Hb <120 in females **B**leeding history **e**GFR<60 or renal dysfuction **T**reatment with antiplatelet agents

Question 26

What is the role of ORBIT?

Answer 26

Helps to assess bleeding risk on anticoagulants

Question 27

AF : Anticoagulation

Answer 27

Long term stroke prevention First line : DOAC - Apixaban 2. Warfarin

Question 28

AF : Post stroke anticoagulation

Answer 28

1. Post TIA : start anticoagulation immediately 2. Post Stroke - commences after 2 weeks

Question 29

Investigation : Palpitations

Answer 29

**First line** 1. ECG 2. Bloods : TFT, U+Es, FBC **Second line - exclude episodic arrhythmia** 1. Holter monitoring for 24 hours or more **Third line** 1. External/Implantable loop recorder\