Atrial Fibrilation

Question 1

Pathophysiology of AF

Answer 1

Contraction of atria is uncoordinated, rapid and irregular, due to disorganised electrical activity that overrides normal SAN

Question 2

Presentation of AF

Answer 2

Palpitations, SOB, syncope, symptoms of associated conditions

Question 3

How does AF impact the ventricles

Answer 3

Irregular conduction to the ventricles resuling in irregular contractions, tachycardia, heart failure (poor filling of ventricles) and risk of stroke

Question 4

Differentials for irregularly irregular pulse

Answer 4

Atrial fibrilation and ventricular ectopies

Question 5

AF appearance on ECG

Answer 5

Absent P waves, narrow QRS complex tachycardia, irregularly irregular ventricular rhythm

Question 6

What is valvular AF

Answer 6

Patients with AF who also have moderate or severe mitral stenosis or mechanical heart valve.

Question 7

Most common causes of AF

Answer 7

Sepsis, mitral valve pathology, ischaemic heart disease, thyrotoxicosis, hypertension

Question 8

Two principles of treating AF

Answer 8

Rate or rhythm control.
Anticoagulation to prevent stroke

Question 9

Options for rate control

Answer 9

Beta blocker
Calcium channel blocker
Digoxin

Question 10

Eg of beta blocker for AF

Answer 10

Atenolol 50-100mg

Question 11

Eg of calcium channel blocker

Answer 11

Diltiazem

Question 12

Which patients should not have rate control first line

Answer 12

If AF is reversible, if AF is new onset, if it is causing HF, if they remain symptomatic despite rate being controlled

Question 13

What is the aim of rhythm control

Answer 13

Return patient to normal sinus rhythm by single cardioversion or long term medical control

Question 14

When is immediate cardioversion given

Answer 14

If AF has been present for less than 48 hours or severely haemodynamically unstable

Question 15

When is delayed cardioversion given

Answer 15

If AF has been present for more than 48 hours and they are stable

Question 16

What should happen to patients while they wait for cardioversion

Answer 16

Put on rate control and anticoagulated for minimum of 3 weeks prior

Question 17

Pharmacological cardioversion options

Answer 17

Flecanide or amiodarone (structural heart disease)

Question 18

Aim of electrical cardioversion

Answer 18

Rapidly shock the heart back into sinus rhythm, involving sedation or general anaesthetic

Question 19

Options for long term medical rhythm control

Answer 19

beta blockers first line
dronedarone
amiodarone (HF or LV dysfunction)

Question 20

What is paroxsymal AF

Answer 20

When AF comes and goes in episodes, usually not lasting more than 48 hours

Question 21

What drug is used for the ‘pill in the pocket’ approach

Answer 21

Flecanide

Question 22

How might paroxsymal AF be managed

Answer 22

‘Pill in the pocket’ approach

Question 23

When can flecanide not be given

Answer 23

In atrial flutter

Question 24

Cardiac causes of AF

Answer 24

Ischaemic heart disease, HTN, rheumatic heart disease, myocarditis

Question 25

Non-cardiac causes of AF

Answer 25

Dehydration, endocrine (hyperthyroidism), infective (sepsis), toxins (alcohol), pulmonary (PE, pneumonia), hypokalaemia, hypomagnesaemia

Question 26

Classification of AF

Answer 26

Acute = <48 hours
Paroxysmal = <7 days
Persistent = >7 days but amendable to CV
Permanent = >7 days not amendable to CV