Ventricular Tachycardias - Prolonged QT Syndrome

Question 1

Definition

Answer 1

Ventricular tachycardia = typically congenital channelopathy disorder were mutation affects cardiac io channels therefore heart conduction, QT interval = 480ms = prolonged QT interval in the ECG finding of prolonged repolarisation of the muscle cells in the heart after a contraction
Can be congenital or acquired

Question 2

Signs

Answer 2

Signs of Andersen=Tawil syndrome
- Micrognathia
- Low-set ears
- Widely spaced eyes

Question 3

Symptoms

Answer 3

Syncope
- syncope from exertion, stress, arousal, or at night
Dizziness
Palpitations
Dyspnoea
Collapse or sudden cardiac death

Question 4

Investigations

Answer 4

ECG - Long QT (QTc > 430ms in males and >450ms in females)
Serum electrolytes: esp K+, Mg2+, Ca2+

Question 5

Management

Answer 5

Conservative: avoid precipitating (e.g., stress and exercise) correct electrolyte imbalance, cease QT-prolonging medication
Beta blocker
Implantable cardioverter-defibrillator (ICD)

Question 6

Complications

Answer 6

Torsade de pointes
Cardiac arrest and sudden death

Question 7

Aetiology

Answer 7

Romano ward syndrome
Jernell-Lange-Neisen Syndrome
Hypokalaemia + Hypocalcaemia
Drugs: Amiodarone, Magnesium