Atrial fibrillation/flutter

Question 1

Define atrial fibrillation

Answer 1

Characterised by rapid, chaotic & ineffective atrial electrical conduction

Question 2

Aetiology of atrial fibrillation

2 + 3 groups of 2º

Answer 2

May be no identifiable cause
Secondary causes lead to an abnormal atrial electrical pathway that results in AF

Systemic causes
Heart causes
Lung causes

Question 3

Epidemiology of atrial fibrillation

age x2, other

Answer 3

VERY COMMON in elderly
Ppresent in 5% of over 65s
May be paroxysmal

Question 4

Presenting symptoms of atrial fibrillation

4

Answer 4

Often ASYMPTOMATIC
Palpitations
Syncope (if low output)
Symptoms of the cause of AF

Question 5

Signs of atrial fibrillation on physical examination

3

Answer 5

• Irregularly irregular pulse
• Difference in apical beat & radial pulse
• Check for signs of thyroid & valvular disease

Question 6

Investigations for atrial fibrillation

3 types

Answer 6

ECG
Bloods
Echocardiogram

Question 7

Management of atrial fibrillation

general + 3 groups

Answer 7

Try to treat any reversible causes (e.g. thyrotoxicosis, chest infection) then 2 main components of management:

Rhythm control
Rate control
Stroke risk stratification

Question 8

Complications of atrial fibrillation

2 +1

Answer 8

THROMBOEMBOLISM

• embolic stroke risk of 4% per year
• risk inc. w/ L atrial enlargement of L ventricular dysfunction

Worsening of existing heart failure

Question 9

Prognosis of atrial fibrillation

Answer 9

Chronic AF in a diseased heart doesn’t usually return to sinus rhythm

Question 10

Subdivisions of atrial fibrillation

Answer 10

• Permanent
• Persistent
• Paroxysmal

Question 11

Aetiology of atrial fibrillation - systemic causes

4

Answer 11

Thyrotoxicosis
Hypertension
Pneumonia
Alcohol

Question 12

Aetiology of atrial fibrillation - heart causes

7

Answer 12

Mitral valve disease
Ischaemic heart disease
Rheumatic heart disease
Cardiomyopathy
Pericarditis
Sick sinus syndrome 
Atrial myxoma

Question 13

Aetiology of atrial fibrillation - lung causes

2

Answer 13

Bronchial carcinoma

PE

Question 14

Investigations for atrial fibrillation - ECG

3

Answer 14

Uneven baseline w/ absent p waves
Irregular intervals between GRS complexes
Atrial flutter = saw tooth

Question 15

Investigations for atrial fibrillation - bloods

4

Answer 15

Cardiac enzymes

TFT

Lipid profile

U&Es, Mg2+ & Ca2+
due to increased risk of digoxin toxicity w/ hypokalaemia, hypomagnesaemia, hypercalcaemia

Question 16

Investigations for atrial fibrillation - echocardiogram

4

Answer 16

May show:
mitral valve disease
left atrial dilatation
left ventricular dysfunction 
structural abnormalities

Question 17

Management of atrial fibrillation - rhythm control

1 >48hr, 2 <48hr, 4 prophylaxis

Answer 17

If >48 hrs since onset of AF
Anti coagulate for 3-4 weeks before attempting cardioversion

If <48 hrs since onset of AF
DC cardioversion
Chemical cardioversion: flecainide or amiodarone

Prophylaxis against AF
Sotalol
Amiodarone
Flecainide
Consider pill-in-the-pocket strategy for suitable patients

Question 18

Management of atrial fibrillation - rate control

4

Answer 18

Chronic AF (permanent)
Control ventricular rate:
digoxin
verapamil
β-blockers
Aim for ventricular rate 90bpm

Question 19

Management of atrial fibrillation - stroke risk stratification
(4)

Answer 19

Low risk patients can be managed w/ aspirin
High risk patients require anticoagulation w/ warfarin
Based on CHADS-Vasc score