Difference between revisions of "QT prolongation"

(Text replacement - " haloperidol" to " haloperidol")
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==Background==
 
==Background==
 
+
*Prolonged ventricular repolarisation --> increased risk of ventricular arrythmias
 
==Clinical Features==
 
==Clinical Features==
 +
*Hisotry may or may not include
 +
**[[Syncope]], [[cardiac arrest]], family history of long QT or sudden death
  
 
==Differential Diagnosis==
 
==Differential Diagnosis==
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==Evaluation==
 
==Evaluation==
 
*[[ECG]]
 
*[[ECG]]
**QTc >440 (male), >460 (female)
+
**quick/imprecise measure: QT takes up more than half the R-R distance
 +
**Measure QT interval in lead II or V5-6
 +
**QTc = QT /√R-R
 +
**Long QT: QTc >440 (male), >460 (female)
 
**>500 = real concern (may result in [[torsades]])
 
**>500 = real concern (may result in [[torsades]])
  

Revision as of 13:44, 8 September 2016

Background

  • Prolonged ventricular repolarisation --> increased risk of ventricular arrythmias

Clinical Features

Differential Diagnosis

Drug List

  • Antiarrhythmics
    • Amiodarone, disopyramide, dofetilide, flecainide, ibutilide, mexiletine, procainamide, quinidine, sotalol
  • Antibiotics
    • Macrolide
      • Azithromycin, erythromycin, clarithromycin
    • Fluoroquinolone
      • Ciprofloxacin, gatifloxacin, gemifloxacin, levofloxacin, moxifloxacin, ofloxacin
    • Other
      • Pentamidine, telithromycin, trimethoprim-sulfamethoxazole
  • Antidepressants
    • Amitriptyline, citalopram, doxepin, fluoxetine, nortriptyline, paroxetine, sertraline, venlafaxine
  • Antiemetics
    • Dolasetron, droperidol, granisetron, ondansetron
  • Antifungals
    • Fluconazole, itraconazole, ketoconazole, voriconazole
  • Antihypertensives
    • Nicardipine
  • Antineoplastics
    • Lapatinib, nilotinib, sunitinib, tamoxifen
  • Antimalarials
    • Chloroquine, halofantrine
  • Antipsychotics
    • Chlorpromazine, clozapine, galantamine, haloperidol, lithium, paliperidone, pimozide, quetiapine, risperidone, thioridazine, ziprasidone
  • Antivirals
    • Amantadine, atazanavir, foscarnet
  • Diuretics
    • Indapamide
  • Immune suppressants
    • Tacrolimus
  • Opiates
    • Methadone
  • Phosphodiesterase inhibitors
    • Sildenafil, vardenafil
  • Skeletal muscle relaxants
    • Tizanidine
  • Urinary antispasmodics
    • Solifenacin

Evaluation

  • ECG
    • quick/imprecise measure: QT takes up more than half the R-R distance
    • Measure QT interval in lead II or V5-6
    • QTc = QT /√R-R
    • Long QT: QTc >440 (male), >460 (female)
    • >500 = real concern (may result in torsades)

Management

Pause Dependent (precipitated by bradycardia)

Adrenergic Dependent (precipited by tachycardia)

Disposition

See Also

External Links

References