Atrial fibrillation + arrhythmias

Question 1

Pathophysiology of AF

Answer 1

Impaired electrical heart activity causing an irregularly irregular rhythm

Question 2

Risk factors for AF

Answer 2

• hypertension
• Coronary heart disease
• mitral stenosis
• pericarditis
• pneumonia
• Hyperthyroidism

Question 3

Presentation

Answer 3

Symptoms:

• palpitations
• dizziness
• syncope
• dyspnoea

Signs:

• tachycardia
• irregularly irregular pulse

Question 4

Investigations

Answer 4

• cardiac examinations
• basic obs
• ECG
• Bloods - FBC, U+Es, TFTs, Trop I
• CXR - for underlying cause such as pneumonia

Question 5

ECG changes

Answer 5

• absent P waves
• wavy baseline
• irregular QRS complexes
• irregularly irregular tachycardia

Question 6

Management rhythm control

Answer 6

• if haemodynamically unstable - DC cardioversion
• if haemodynamically stable - check time of onset

Within 48 hrs:

• DC cardioversion
• or chemical cardioversion

Longer than 48hrs:

• anticoagulation with warfarin
• for 3 - 4 weeks
• cardioversion after
• or TOE to rule out clots

Question 7

Chemical cardioversion

Answer 7

Flecainide - contraindicated in IHD

Amiodarone - 1st line in AF with HF

Question 8

Rate control

Answer 8

• diltiazem CCB
• beta blocker
• digoxin

If one drug does not help, can use a combination of 2

Question 9

CHADSVAS score management

Answer 9

Stroke risk stratification:
- low risk - 0 in males and 1 in females - no treatment

• medium - 1 in males and 2 in females - consider treatment
• high risk - 2+ in males and 3+ in females - warfarin

Question 10

CHADSVASC scoring

Answer 10

Congestive HF - 1 
HTN - 1 
Age 75+ - 2
DM - 1
Stroke/TIA - 2 
Vascular disease - 1 
Age - 65 - 74 - 1
Sex = Female - 1 

Max score = 9

Question 11

SVT

Answer 11

Problem with SAN, AVN or atrium
High HR
Anomaly with P waves or PR interval
Normal QRS

Narrow complex tachycardia - SVT

Question 12

VT

Answer 12

Problem with ventricles, Bundle of His or Perkinje fibres
High HR due to ventricle pathology
Normal P waves
Broad QRS

Broad complex tachycardia - VT

Question 13

Indication for electrical DC cardioversion

Answer 13

Persistent AF for more than 48 hours

Haemodynamically unstable

Question 14

Commonest causes of AF

Answer 14

IHD
Hyperthyroidism
Hypertension

Question 15

Wolff Parkinson White syndrome cause, ECG changes and symptoms

Answer 15

Accessory pathway causing inappropriate pathway of conduction

• palpitations
• delta wave and short PR interval on ECG

Question 16

Atrial flutter pathophysiology

Answer 16

APs continually travelling around right atrium dependent on tissue from IVC and tricuspid valve

Question 17

Atrial flutter signs on ECG

Answer 17

2:1 P wave: QRS

Saw tooth appearance

Question 18

LBBB

Answer 18

Broad QRS - more than 3 small squares
Negative QRS complex in leads V1 - V4
Positive QRS in V6
Left axis deviation

Question 19

RBBB

Answer 19

Broad QRS - more than 3 small squares
V1 has bunny ear positive QRS appearance
Slurred S wave in V6

Question 20

How to calculate HR from ECG

Answer 20

Regular: 300/squares between R-R

Irregular: how many QRS complexes in 30 squares x 10

Question 21

Long term Pharmacological treatment of permanent AF

Answer 21

1. DOAC - apixaban
2. Rate control - beta blocker
3. Rhythm control

If failed - ablation

Question 22

Respiratory causes of AF

Answer 22

Chest infection

Lung cancer

Question 23

Systemic causes of AF

Answer 23

Excessive alcohol
Hyperthyroidism
DM

Question 24

Management of paroxysmal AF

Answer 24

Self limiting
Pill in pocket - sotalol or flecainide
Anticoag - CHADVASC

Question 25

Type of AF

Answer 25

Paroxysmal - terminates spontaneously within 7 days Persistent AF - lasts more than 7 days but terminates Permanent - long term continuous AF, sinus rhythms not achievable

Question 26

Why is anticoagulant given for 3 weeks before rythmn control drugs

Answer 26

Rhythms control drugs may mask clots

Question 27

When to give rhythm control first line in Persistent AF management

Answer 27

young < 65 yo Symptomatic Presenting first time Secondary to already treated precipitant

Question 28

Atrial flutter mx

Answer 28

Manage as for AF • Amiodarone to restore sinus • Amiodarone or sotalol to maintain it

Question 29

Contraindications for beta blockers

Answer 29

Asthma

Question 29

Catheter ablation

Answer 29

1. Anticoagulate 4 weeks before procedure 2. Percutaneous procedure via groin 3. Still require anti coagulation lifelong after

Question 30

Complications of catheter ablation

Answer 30

Cardiac tamponade Stroke Pulmonary valve stenosis

Question 31

If CHADVAS = 0 - 1

Answer 31

Ensure a transthoracic echocardiogram has been done to exclude valvular heart disease

Question 32

SVT management

Answer 32

1. Vagal manoeuvre- vasalva or carotid sinus massage 2. IV adenosine - if asthmatic give verapamil 3. Electric cardio version

Question 33

Broad complex tachycardia

Answer 33

Regular - amiodarone Irregular - refer to cardiologist