Palpitations and Dysrhythmias

Question 1

Is a patient with AF likely to be tachycardic or bradycardic?

Answer 1

Tachycardic - the lack of input from the vagus nerve (parasympathetic) means that the ventricles begin beating under their own rate which is slightly above the baseline set by the atrial rhythm

Question 2

What are some common causes of AF in the patient in the ED?

Answer 2

Idiopathic / incidental finding - a very common way to identify AF is just by finding an irregularly irregular heart beat on a cardiac work up
HOLIDAY HEART - Lots of drugs and alcohol
IHD
NON-CARDIAC - Sepsis, PE, thyrotoxicosis, electrocution, Lung or pleural disease, chest trauma
PAROXYSMAL - can occur in some athletes

Question 3

What is paroxysmal AF? Is it concerning?

Answer 3

Paroxysmal AF is when there is fibrillation but it is transient - this is more concerning than baseline AF because with improper contraction of the atria there is stasis and coagulation of blood (mural thrombi form) and when the heart starts beating normally again these clots are thrown off into systemic circulation leading to PE and strokes.

Question 4

What ECG changes do you see in AF?

Answer 4

Absent p waves

Tachycardia

Question 5

What other investigations should you do in a patient with probable AF?

Answer 5

ECG
Echo
BLOODS: FBC (anaemia), TFT, U&E, HbA1c, lipids

Question 6

How do we predict risk in AF?

Answer 6

CHADSVasC score - risk of thromboembolism 
Congestive heart failure
Hypertension
Age (60-64=1, >75 =2)
Diabetes 
Stroke 
Vascular disease
Sex (female=1)

Question 7

If you decide someone is at high risk of thromboembolism how should you consider treating them?

Answer 7

DOAC (e.g. rivaroxaban, apixaban)
Warfarin
BETA-BLOCKER will also help with rate control e.g. atenolol, metoprolol or consider diltiazem (non-dihydropyridine CCB)

Question 8

How do we assess someone’s bleeding risk once they have been put on anti-coagulant therapy?

Answer 8

HASBLED 
Hypertension
Abnormal liver function (clotting fx)
Stroke 
Bleeding
Labile INR 
Elderly 
Drugs and alcohol

Question 9

When should you consider cardio version in a case of AF? How should this be done?

Answer 9

• In new onset AF
• If there is an identified reversible cause
• If someone’s heart failure is thought to be the cause for their AF

DC current shock or medically with Flecainide 50-150mg IV
Amiodarone 300mg

***risk of stroke when cardioverted because coordinated contraction with throw off clots formed in static blood

Question 10

What is complete heart block?

Answer 10

Complete, or third degree heart block is where there is a totally absence of communication between the conduction/contraction in the atria and the ventricles - the two beat independently

Question 11

How is complete heart block likely to present?

Answer 11

Because the atria aren’t contracting properly they are not priming the ventricles with blood before they contract.
Cardiac output plummets and people will present with COLLAPSE and are in CARDIOGENIC SHOCK
Patients might have chest pain, palpitations and have pulmonary oedema resulting in breathlessness

Question 12

What is the most common cause of heart block?

Answer 12

Cardiac ischaemia
SPECIFICALLY inferior wall MI
Will often lead to narrow QRS complex

Question 13

How long should the P-R interval be?

Answer 13

No longer than 200ms (5 small squares)

Question 14

What tests should be done in someone who has heart block?

Answer 14

FBC, U&E, Mg, Ca, TFTs, ECG (ask about previous ischaemic changes and FH of cardiac problems as well as DH)

Question 15

How should you managed heart block in the ED?

Answer 15

Manage symptoms
Refer to cardiology
Manage ischaemia if you think its ongoing

Question 16

What is a narrow complex SVT?

Answer 16

Rate >100 and QRS complex <120ms in width (3 squares)

Question 17

What are some symptoms of SVT?

Answer 17

Chest pain 
Palpitations 
Feeling faint 
Sweating 
Shortness of breath
Syncope 
Cardiogenic shock (hypotensive)

Question 18

What are some causes of SVT?

Answer 18

AF
Holiday heart
Atrial flutter
Paroxysmal SVT 
WPW syndrome

Question 19

If you did an ECG and it showed tachycardia but the QRS complexes were not <120ms in width then what would you suspect?

Answer 19

Sinus tachycardia

Question 20

What characteristic ECG change will you see in WPW syndrome?

Answer 20

Delta waves before the QRS complexes

Question 21

Other than ECG what investigations should you do in a patient with SVT?

Answer 21

Echo

BLOODS: FBC, U&E, Trop, TFTs, Ca, Mg

Question 22

How should you treat a narrow complex SVT?

Answer 22

Give oxygen and gain IV access