Atrial fibrillation

Question 1

Structural abnormalities

Answer 1

Dilated atria

Fibrosis of atrial muscle

Question 2

Physiological abnormalities

Answer 2

Pacemaker (sinus node) overwhelmed by disorganised atrial electrical discharge- often originating at pulmonary vein insertion

Question 3

Prior events

Answer 3

Hypertension
Primary heart diseases (e.g. coronary artery disease)
Lung diseases (e.g. pneumonia, cancer, PE)
Alcohol
Hyperthyroidism
Heart failure

Question 4

Symptoms

Answer 4

Palpitations, tired/breathless with exercise, chest tightness (angina), oedema

Question 5

Signs

Answer 5

Irregular pulse (irregularly irregular)
Signs of underlying cause (high BP, lung disease, valve murmur, weight loss-hyperthyroidism)

Question 6

ECG

Answer 6

irregular heart beat with absent P waves

Question 7

Medical/surgical intervention

Answer 7

Rate control (slow down heart rate –> prevents palpitations and improves efficiency of heart beat), rhythm control, pulmonary veins can be electrically isolated, warfarin to prevent clots

Question 8

Drugs used to control heart rate

Answer 8

digoxin, beta blockers and verapamil

Question 9

How is rhythm controlled?

Answer 9

Drugs: amiodarone

electrical shock treatment: DC (direct current) cardioversion