What are the causes of Prolonged QT interval?

Prolonged QT interval: 

The causes of the prolonged QT interval are followings:

Congenital causes of the prolonged QT interval:

• Jervell-Lange-Nielsen (JLN) syndrome: (includes deafness and is due to an abnormal potassium channel)
• Romano-Ward syndrome: (no deafness)

Drugs that Induce prolongation of QT interval: 

• Amiodarone
• Sotalol
• Class 1a antiarrhythmic drugs
• TCA (e.g. amitriptyline) (˃SSRI)
• SSRI (especially citalopram, Sertraline)
• Lithium
• Methadone
• Chloroquine
• Mefloquine
• Terfenadine
• Macrolides: Erythromycin, Clarithromycin
• Levofloxacin
• Domperidone
• Ketoconazole
• Haloperidol
• Tacrolimus

Other causes:

• Electrolyte: Hypocalcaemia, Hypokalemia, Hypomagnesaemia
• Acute MI
• Myocarditis
• HOCM
• Hypothermia
• Subarachnoid haemorrhage
• Hypothyroidism

Source:

• https://litfl.com/qt-interval-ecg-library/
• Step Up to MRCP Review note for Part 1 and 2 by By Dr Khaled El Magraby; page: 8