Chapter 4: Arrythmias

Question 1

What is an arrhythmia? List some examples

Answer 1

Abnormal heart rhythm caused by problems in the conduction system of the heart.

Question 2

What are the general symptoms of arrhythmia?

Answer 2

Palpitations 
SOB
Tired
Dizziness
Chest pain

Question 3

What are the main types of arrhythmia?

Answer 3

AF

Question 4

What are ectopic beats and how are they managed?

Answer 4

Atrial fibrillation
Ventricular tachycardia
Paroxysmal supraventricular tachycardia

Question 5

What is the most common type of arrhythmia?

Answer 5

Premature heart beats often caused by a missed or extra beat.
Treatment is rarely required. If very bothersome BB are sometimes effective

Question 6

What are some of the possible causes of Atrial fibrillation?

Answer 6

CVDs
Congenital (heart defects from birth)
Lifestyle: medication, alcohol abuse, infection

Question 7

What should ALL patients with AF be assessed for?

Answer 7

Stroke and bleeding risk

Question 8

What is the main complication of AF and how is it managed?

Answer 8

Stroke and Heart failure

Question 9

What are the THREE broad categories for managing AF?

Answer 9

Rate control
Rhythm control
Cardioversion

Question 10

What are the signs of haemodynamic instability?

Answer 10

Haemodynamic stability describes how stable blood flow is. If a person Is haemodynamically stable that means they have a stable pumping of the heart and good circulation of blood.

• Low BP
• Abnormal heart rate
• Chest pains

Question 11

What is the treatment option for a patient presenting with an acute onset of AF WITH life threatening haemodynamic instability?

Answer 11

Emergency electrical cardioversion

Question 12

What is the treatment option for a patient presenting with an acute onset of AF WITHOUT life threatening haemodynamic instability?

Answer 12

If the onset of arrythmia <48 hours = rate or rhythm control
If the onset of arrythmia >48 hours or uncertain = rate control

Question 13

Why is it essential to have an anticoagulant 3 weeks before cardioversion?

Answer 13

Cardioversion increases risk of blood clot forming. However, in an emergency 3 weeks cannot be waited hence a parenteral anticoagulant is given.

Question 14

What drugs are used for pharmacological cardioversion for people with no evidence of structural or IHD

Answer 14

IV amiodarone or flecainide

Question 15

Which drug is preferred for pharmacological cardioversion in people with evidence of structural heart disease?

Answer 15

Amiodarone

Question 16

Describe the dosing directions for amiodarone?

Answer 16

200mg tds for 7 days
200mg BD for 7 days
200mg OD maintenance dose

Question 17

What are the patient counselling for those on amiodarone?

Answer 17

Photo toxic reactions - patients on amiodarone should be advised to shield from sunlight during treatment and several months after. Always put high SPF sun cream.

Corneal micro deposits- may interfere with drivers and may become dazzled at night.

Thyroid function tests- amiodarone contains iodine and cause thyroid dysfunction

Pneumonia and pulmonary fibrosis should always be suspected if new progressive SOB or dry cough develops in person taking amiodarone.
Hepatoxicity – discontinue if severe liver function abnormalities e.g., jaundice

Question 18

List the top interactions with Amiodarone

Answer 18

Coumarins (warfarin)- amiodarone inhibits metabolism of coumarins –> risk of bleeding

Beta blockers- increases risk of bradycardia, AV block and Myocardial depression.

Lithium

Digoxin, non-dihydropyridines CCB- need to halve dose of digoxin if giving to together.

Question 19

What SHOULD NOT be offered as pharmacological cardioversion for those with an acute onset of AF?

Answer 19

Magnesium or CCB

Question 20

What is the first line of treatment for long term maintenance therapy of AF?

Answer 20

1st line= rate control
Monotherapy 
BB (not sotalol)
CCB (diltiazem or verapamil) 
Digoxin (in sedentary patients with non-paroxysmal AF) 
Dual therapy 
BB 
Diltiazem 
Digoxin (in sedentary patients with non-paroxysmal AF)

Question 21

Which Betablockers should be avoided in rate control treatment for AF?

Answer 21

Sotalol

Question 22

What should be given if first line of treatment fails?

Answer 22

Rhythm control

Question 23

Who should not receive rate control in the treatment of AF?

Answer 23

Those with a new onset of AF
AF which has a reversible cause
Atrial flutter who is suitable for ablation strategy to restore sinus rhythm
For those whom rhythm control is more suitable based on clinical judgement

Question 24

What are the 2 assessment tools used for determining risk of stroke and bleeding?

Answer 24

CHA2DS2VASc = stroke risk 
HASBLED = Bleeding risk

Question 25

Using the stroke risk assessment tool when should an anticoagulant be given?

Answer 25

If CHADSVAS score of 2 or more = give anticoagulant | If stroke risk outweighs that of the bleeding risk, then an anticoagulant should be given.

Question 26

Ventricular tachycardia is a type of arrythmia. What are the 4 main types of ventricular tachycardia and the management of each one?

Answer 26

Pulseless = Immediate defibrillation and CPR If ineffective = IV amiodarone (lidocaine if CI) Unstable sustained = Direct cardioversion If ineffective = IV amiodarone Stable sustained = IV anti-arrhythmic drug (amiodarone preferred) Non-sustained = BB given

Question 27

What is torsade de pointes?

Answer 27

Torsade de pointes is a lethal form of ventricular tachycardia with a prolonged QT interval.

Question 28

How is torsade de pointes managed?

Answer 28

IV magnesium sulphate

Question 29

What causes torsade de pointes?

Answer 29

Drugs Diahorrea Low serum magnesium

Question 30

Which drugs cause Torsade de pointes / QT prolongation?

Answer 30

Antiarrhythmics – Disopyramide, procainamide, quinidine, sotalol Macrolides – Azithromycin, clarithromycin, erythromycin Fluoroquinolones- Ciprofloxacin, levofloxacin, moxifloxacin Antifungals – Azoles (e.g., fluconazole etc.) Antipsychotics- haloperidol, thioridazine Antidepressants- citalopram, escitalopram Antiemetics- ondansetron Opioids- methadone Misc- cocaine, donepezil

Question 31

What is pill in the pocket?

Answer 31

An approach when you only take a flecainide 300mg or propafenone tablet when you have an episode of AF. This requires you to always carry the medication with you. It is used for people who have paroxysmal AF who has been assessed suitable by a cardiologist.

Question 32

What are the signs of digoxin toxicity?

Answer 32

``` bradycardia N&V, diarrhoea abdominal pain blurred vision/ yellow skin Confusion delirium rash ```

Question 33

How is paroxysmal supraventricular tachycardia managed?

Answer 33

Reflex vagal nerve stimulation e.g., carotid sinus massage, immerse face in ice cold water, Valsalva manoeuvre IV adenosine (CI in COPD and ASTHMA) IV Verapamil In patients who are haemodynamically unstable = direct current cardioversion In patients with recurrent episodes= catheter ablation OR drugs (verapamil, diltiazem, BB , flecainide or propafenone).

Question 34

What can be used to treat an arrythmia after an MI?

Answer 34

Lidocaine | Disopyramide

Question 35

What should you do if both flecainide and amiodarone are used together?

Answer 35

Reduce dose of flecainide by half when concurrent use with amiodarone.