Supraventricular Tachycardias - AVRT (Wolff-Parkinson White Syndrome)

Question 1

Definition

Answer 1

AVRT - means an accessory pathway exists for impulse conduction, not re-entry through AVN. OFTEN HEREDITORY

Question 2

Most common example of AVRT

Answer 2

Wolff-Parkinson White

Question 3

Pathophysiology

Answer 3

Accessory pathway for conduction = BUNDLE OF KENT - the impulse can travel to the AVN but also to the ventricle quicker
PRE-EXCITMENT SYNDROME = excites ventricles earlier than typical pathway = why you see delta waves

Question 4

Risk factors

Answer 4

Ebstein’s Anomaly
Hypertrophic cardiomyopathy
Mitral valves prolapse
Atrial septal defect

Question 5

Aetiology

Answer 5

Congenital
Hypokalaemia
Hypocalcaemia
Drugs: amiodarone, TTA
Bradycardia
Acute MI
Diabetes

Question 6

Signs and Symptoms

Answer 6

Palpitations
Severe dizziness
Dyspnoea
Syncope

Question 7

Diagnosis

Answer 7

ECG
- Slurred DELTA WAVES
- Short PR interval
- Wide QRS complex

Question 8

Treatment

Answer 8

FIRST LINE = Valsalva manoeuvre carotid massage (blow into syringe, vs resistance)
SECOND LINE = IV Adenosine (will temporally cease conduction (WARN PATIENT = FEEL LIKE DYING) = 6mg, then 12mg, then another 12mg (additional doses if initial 6mg unsuccessful)
THIRD LINE = Consider surgical radiofrequency ablation of bundle of Kent