Condition - Atrial Fibrillation

Question 1

Clinical features - symptoms

Answer 1

Palpitations
Dyspnoea
Chest pain
Dizziness

Question 2

Clinical features - signs

Answer 2

Irregularly irregular pulse
Tachycardia (120-180 bpm)
Absent p waves

Question 3

Aetiology

Answer 3

Regular electrical impulses generated by the SA node are overwhelmed by disorganised electrical impulses generated in the atria, these impulses can be conducted through the atrioventricular node resulting in contraction of the ventricles.

This results in an irregularly irregular and tachycardic pulse.

Most common underlying causes are hypertension and heart failure, also hyperthyroidism, alcohol and rheumatic heart disease. Anything that causes increased pressure in or remodelling of the atria.

Question 4

Treatment

Answer 4

Initial management:
Direct current cardioversion - if hypotensive/unstable
Chemical cardioversion - flecainide, amiodarone

Long term management:
Rate control - digoxin/beta blocker/amiodarone
Oral anticoagulant - warfarin
Electrophysiological ablation

Treat underlying condition (thyroid)

Question 5

Investigation

Answer 5

ECG
FBC
Chest radiograph
Echocardiogram

Question 6

Differential diagnosis

Answer 6

Thyrotoxicosis
Alcohol intoxication
Rheumatic heart disease (mitral stenosis)
Heart failure