KCP: Palpitations and Syncope Flashcards
What is Syncope?
Loss of consciousness due to cerebral perfusion
What is presyncope?
The lightheadedness experienced by someone who feels like they might be about to lose consciousness
What do you call a fast heart rate?
Tachycardia
What do you call a slow heart rate?
Bradycardia
What do you call an irregular heart beat?
Arrhythmia
Definition of tachycardia?
> 100 bpm
Definition of bradycardia?
< 60 bpm
How do you calculate heart rate from an ecg?
Does this patient have an irregular heart beat?
Count number of big squares between R waves
R-R=2.4 squares
Divide 300 by this number = 125 bpm
Patient is tachycardic
How is time represented on an ecg?
Each square is 0.2s
Therefore there is 300 squares per minute
Therefore:
beats per minute = 300 / squares per beat
Common arrhythmias for too fast, too slow and intermittent
Too fast
* Atrial fibrillation
* Ventricular tachycardia
* Supraventricular tachycardia
Too slow
* Heart block
Intermittent
* Paroxysmal supraventricular tachycardia
* Paroxysmal AF
* Ectopic beats
What is Paroxysmal Supraventricular Tachycardia? (SVT)
Intermittent rapid tachycardia with abrupt onset and offset
What is supraventricular tachycardia also known as?
It is a called a narrow complex tachycardia
What does an ECG look like in SVT?
QRS complexes are of normal duration (< 3 small squares, < 120 ms)
So electrical impulse is following the normal ventricular conduction pathway, but at a fast rate
SVT Presentation
- Palpitations
- Often had previous episodes that spontaneously reverted
- Light headedness
- Nausea
- Chest pain
- Breathlessness
- Usually haemodynamically stable
Which nerve do you need to activate in order to treat SVT symptoms?
Vagus Nerve
Vagus nerve is involved in the parasympathetic nervous system, activation releases acetylcholine acting on the muscarinic receptors thus slowing down conduction on the atrioventricular node
How can you activate the vagus nerve?
- Carotid sinus massage
- Valsalva manoeuvre
- Cold water on the face i.e. a diving response
- Modified Valsalva manoeuvre
What is the valsalva manoeuvre
“Popping your nose”
What is Ventricular Tachycardia?
It is a broad complex tachycardia
What can Ventricular Tachycardia imply?
Patients normally have underlying heart disease
What is going on in this ECG?
QRS complexes are of increased duration (>3 small squares, >120 ms)
So electrical impulse most likely originates in the ventricle and not following a normal conduction pathway.
It is fast and abnormal therefore is Ventricular Tachycardia
VT-Presentation?
- Palpitations
- Chest pain
- Shortness of breath
- Loss of consciousness
Briefly describe the ECGs of first, second and third degree heart block
What’s going on with this ECG?
Complete heart block
Presentation of complete block?
- Syncope and pre-syncope
- Fatigue
- Breathlessness
- Cardiac arrest
- Usually have underlying heart disease
Complete heart block short term treatment?
We want to inhibit the vagus nerve which is a muscarinic cholinergic agonist.
There fore we need a muscarinic cholinergic antagonist.
This is Atropine
Complete heart block long term treatment?
Pacemaker
What is going on in this ECG?
Atrial Fibrillation
Atrial Fibrillation Presentation
- Incidental finding
- Palpitations
- Breathlessness
- Fatigue
- Can be made worse by alcohol
AF treatment?
Increase block at the AV node
- Beta-adrenergic receptor blockers e.g. bisoprolol
- Calcium channel antagonist e.g. diltiazem
What other complication can AF lead to?
Stroke
- Clot forms in fibrillating left atrium
- Emboli can then pass to cerebral circulation leading to a stroke
What is…
Is a metric used to assess the risk of osmeone having a stroke.
If score is 1 consider anti-coagulant
If score is > 2 anti-coagulant and anti-platelet
Biggest risk from untreated atrial fibrillation
Stroke
This rhythm can lead to systemic emboli. Patients are normall started on anticoagulation. It may also increase risk of heart failure.
What would you use atropine for?
Short term treatment for complete heart block
What would you use adenosine for?
A heart condition marked by episodes of rapid heart rate (paroxysmal supraventricular tachycardia)
