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QTc calculator
Example:
(standard paper speed 25 mm/sec)
n1 = 9
n2 = 24
Congenital/Hereditary (long QT syndrome/channelopathies)
Acquired causes of long QT
Anorexia nervosa, Alcohol
Bradycardia, Brain
Coronary artery disease, Cardiomyopathy
Drugs (see below), Diet (liquid protein)
Electrolyte imbalance (hypokalemia, hypocalcemia, hypomagnesemia), Endocrine (hypothyroid)
Drugs causing QT interval prolongation
Anti-Arrhythmics e.g. procainamide, disopyramide, Amiodarone, Sotalol
Anti-Anginals e.g. Ranolazine
Anti-Biotics e.g. Macrolides, Fluoroquinolones, Bactrim, azoles
Anti-psyChotics: 1st gen>2nd gen (chlorpromazine, haloperidol, risperidone)
Anti-Depressions: SSRIs, TCAs
Anti-Emetics: (5-HT3 antagonists) ondansetron, also droperidol
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