Palpitations and Syncope

Question 1

What is syncope?

Answer 1

Syncope - Loss of consciousness due to reduced cerebral perfusion

Having a witness account is important for diagnosis

Question 2

What is pre-syncope?

Answer 2

Presyncope usually refers to lightheadedness when some feels they may be about to lose consciousness

Question 3

What are common causes of syncope?

Answer 3

1. Cardiovascular – reducing perfusion
2. Postural – most common
3. Neurally mediated – epilepsy
4. Neural reflex syncope – exacerbated by stress and anxiety – vagal activity increases – blood pressure drops and someone loses consciousness
5. Drug intoxication
6. Hypoglycaemia – people not receiving their medication for diabetes – metformin rarely does it

Question 4

What are palpitations? What are questions you should be thinking about?

Answer 4

Palpitation - heart beat becomes noticeable

Thumping, feel their heartbeat, racing heart, feeling an extra beat followed by a refractory period - people commonly feeling palpitations at night

Questions
1. Frequency
2. Duration,
3. Triggers - caffine and alcohol
4. Speed of palpitation – fast (tachycardia) or slow (heart block)
5. Regular and irregular? – can be a mix = regularly irregular - Get them to tap out the beat

Question 5

In the hearts electrical system, where can abnormalities arise?

Answer 5

Abnormalities can occur at any point in the cascade

Question 6

How can you calculate heart rate from an ECG?

Answer 6

Count the number of large squares between R waves and use that number to divide 300 - gives an approximate heart rate

Works when you have a regular sinus rhythm

Question 7

What is sinus arrhythmia?

Answer 7

Change in heart as you breath – due to changes in atrial stretch

Question 8

What are examples of common arrhythmias that present?

Answer 8

Atrial fibrillation - most common

Intermittent - normally associated with a fast rhythm

Question 9

What is supraventricular tachycardia (SVT)?

Answer 9

SVT - Intermittent rapid tachycardia with abrupt onset and offset - sudden beats faster than normal

Narrow complex tachycardia - QRS complexes are of normal duration (< 3 small squares, < 120 ms)

Electrical impulse is following the normal ventricular conduction pathway, but at a fast rate

Question 10

How does supraventricular tachycardia present?

Answer 10

SVT-presentation

1. Palpitations - Often had previous episodes that spontaneously reverted
2. Light headedness - usually no loss of consciousness
3. Nausea
4. Chest pain
5. Breathlessness
6. Usually haemodynamically stable - means that blood pressure is sufficient to maintain organ perfusion

Question 11

Activation of which nerve can increase the blockade at the AV node? How can this nerve be stimulated?

Answer 11

Vagus nerve-parasympathetic -acetylcholine acting on muscarinic receptors (M2)

Stimulate the vagus nerve by…
1. Carotid sinus massage
2. Valsalva manoeuvre
3. Cold water on the face i.e. a diving response
4. Modified Valsalva manoeuvre

If the vagal manoeuvres don’t work, one can…
- Give intravenous adenosine-which slows conduction through the AV node

Question 12

What is ventricular tachycardia? How does it appear on an ECG?

Answer 12

VT - fast heart rate originating from the ventricles

Characterized by tachycardia + broad complex (longer than 3 small squares)

Question 13

How does ventricular tachycardia present?

Answer 13

1. Palpitations
2. Chest pain
3. Shortness of breath
4. Loss of consciousness

Question 14

How is ventricular tachycardia treated?

Answer 14

If unconscious or with very low blood pressure…

Need urgent synchronized DC cardioversion - Pads - Synchronized to the R wave - Medical emergency

Stable patients – give anti-arrhythmic medication

Question 15

What are the different types of heart block?

Answer 15

2:1 atrioventricular block is a form of second-degree AV nodal block and occurs when every other P wave is not conducted through the AV node to get to the ventricles, and thus every other P wave is not followed by a QRS complex.

Question 16

What is complete heart block?

Answer 16

Complete Heart Block - P waves and QRS complex are dissociated - running at different rates

Usually means there is a problem in the AV node – e.g. due to ischemic heart disease damage

Question 17

How does complete heart block present in patients?

Answer 17

Key symptom - Fatigue – heart rate is irregular and dissociated – blood pumping is extremely inefficient

Question 18

What medication/treatment is used to treat complete heart block?

Answer 18

Targetting - Vagus nerve, parasympathetic, muscarinic cholinergic agonist - slows down AV conduction

Treatment involves a muscarinic cholinergic antagonist - Atropine - used for symptomatic heart block – but not a long term solution

Definitive treatment involves a cardiac pacemaker

Question 19

What is atrial firbillation?

Answer 19

Atrial firbillation - AF

Most common sustained cardiac arrhythmia
Lifetime risk over age of 40 is 25%

ECG
1. No regular P waves
2. Disorganized Atrial activity with intermittent conduction down to the ventricle

Question 20

How does atrial fibrillation normally present?

Answer 20

Atrial Fibrillation-Presentation

1. Incidental finding
2. Palpitations
3. Breathlessness
4. Fatigue
5. Can be made worse by alcohol

Question 21

How is atrial firbillation treated?

Answer 21

Treatment can be rhythm control and rate control focused

Focus on rate control - reduce activity from atrium going down into the ventricle

Increase block at the AV node – calcium channel antagonist (diltiazem) or beta-adrenergic receptor blocker (bisoprolol)

Question 22

How does AF increase the risk of stroke?

Answer 22

Atrial fibrillation is very common and a major preventable cause of stroke

Clot forms in fibrillating left atrium (blood pools/clot forms) - Emboli can then pass to cerebral circulation leading to a stroke

Risk of stroke calculated using CHA2DS2-VAScScore - give a risk for stroke

Question 23

If someone has a high risk of stroke, what medications could be consider putting them on?

Answer 23

Offer anticoagulant
1. Apixaban
2. Rivaroxaban
3. Warfarin

First two are more common - warfarin is harder to control

Question 24

Explanation for the cause of supraventricular tachycardia (SVT)?

Answer 24