title: Iohexol contrast medium induces QT prolongation in amiodarone patients.
abstract: OBJECTIVE
  Amiodarone is widely used in ventricular tachyarrhythmias and atrial fibrillation, known to prolong QT-intervals. Concurrent administration of drugs prolonging QT- time can induce life-threatening ventricular tachyarrhythmia.
  
  
  METHODS
  QT-interval changes following use of Iohexol contrast-medium for coronarangiography were observed comparing 21 patients taking long-term amiodarone therapy with 21 controls not taking amiodarone or QT-prolonging drugs retrospectively.
  
  
  RESULTS
  Concurrent use of Iohexol and amiodarone was associated with significant prolongation of QTc-interval (433, 95%CI: 419-448 ms vs. 480, 95%CI: 422-483 ms, P < 0.001) the day after coronarangiograpgy. 6/21 patients showed severe prolonged QTc-interval of >500 ms.
  
  
  CONCLUSIONS
  Caution is advised until more is known about pro-arrhythmic effects of Iohexol.
authors.affiliation: Friedrich-Schiller-University, Clinic of Internal Medicine III, Erlanger Allee 101, D-07740 Jena, Germany. Matthias.Goernig@med.uni-jena.de
authors.forename: Matthias
authors.initials: M
authors.lastname: Goernig
authors.forename: Thomas
authors.initials: T
authors.lastname: Kirmeier
authors.forename: Andreas
authors.initials: A
authors.lastname: Krack
authors.forename: Christiane S
authors.initials: CS
authors.lastname: Hartog
authors.forename: Hans R
authors.initials: HR
authors.lastname: Figulla
authors.forename: Uwe
authors.initials: U
authors.lastname: Leder
mesh_terms: D000638:Amiodarone / Q000627:therapeutic use*; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use*; D003287:Contrast Media / Q000009:adverse effects*; D006801:Humans; D007472:Iohexol / Q000009:adverse effects*; D008133:Long QT Syndrome / Q000139:chemically induced*; D012189:Retrospective Studies; D017180:Tachycardia, Ventricular / Q000188:drug therapy*
chemical_list: D000889:Anti-Arrhythmia Agents; D003287:Contrast Media; D007472:Iohexol; D000638:Amiodarone