Arrhythmias - Supraventricular Tachycardia Flashcards
1
Q
ESSENCE
A
Tachyarrhthmia that originates above ventricles (eg atrial or atrioventricular node tissues)
2
Q
Also called
A
Paroxysmal supraventricular tachycardia (SVT)
3
Q
TYPES
A
- Based on source of electrical signal
- Atrioventricular nodal re-entrant tachycardia - reentry point back through AV node
- Atrioventricular re-entrant tachycardia - reentry point is accessory pathy (Wolff-Parkinson-White syndrome)
- Atrial tachycardia - originates somewhere in atria other than sinoatrial node, not caused by re-entering signal from ventricles
4
Q
AETIOLOGY
Precipitating factors
A
- Excessive caffeine or alcohol
- Hyperthyroidism
- Illic drug use
5
Q
CLINICAL FEATURES
Symptoms
A
- Palpitations
- Anxiety
- Presyncope/lightheadedness
- Chest pain
6
Q
CLINICAL FEATURES
Signs
A
Tachycardia
7
Q
INVESTIGATIONS
First choice
A
- ECG
- Holter monitoring
8
Q
ECG findings
A
- Tachycardia
- Narrow or wide QRS complex
- If wide must be differentiated from ventricular tachycardia
- Wide seen in SVT if there is bundle branch block or accessory pathway
9
Q
MANAGEMENT
Options
A
- Conservative
- Vagal maneuvers
- Medical
- IV adenosine
- AV nodal blocking agents (beta blockers/CCB)
- Procedural
- Synchronised cardioversion
- Radiofrequency catheter ablation
10
Q
MANAGEMENT
Exmaples of vagal maneuovres
A
- Carotid sinus massage
- Valsalva
- Facial immersion in ice or cold wet towel
11
Q
Vagal maneuvers indication
A
First step in stable patient
12
Q
IV adenosine indication
A
Stable patient unresponsive to vagal maneuvers
13
Q
Indication for synchronised cardioversion
A
Haemodynamically unstable patients
14
Q
Indication for radiofrequency catheter ablation
A
Best long term therapy for SVT
15
Q
COMPLICATIONS
Main one
A
Tachycardia mediated cardiomyopathy
