title: An evaluation of ECG leads used to assess QT prolongation.
abstract: OBJECTIVE
  The aim of the present study is to elucidate the optimal lead to be selected for the evaluation of drug-induced QT prolongation.
  
  
  RESULTS
  We assessed the validity of each electrocardiography (ECG) lead for the evaluation of QT intervals in 688 patients receiving psychotropic drugs. Abnormal QTc prolongation was observed in 96 (14%) patients using the longest ECG lead. Prevalence of QTc prolongation was larger when using leads I, III, aVR, aVL, aVF, V1, and V6 (> 18%), and smaller when using lead V2 (10%). In the remaining 4 ECG leads, the overall accuracy to predict QTc prolongation was higher when using lead V3 (94%) compared with lead II (89%) or lead V5 (90%). Sensitivity to predict QTc prolongation was higher when using lead V4 (81%) compared with lead II (66%) or lead V2 (63%).
  
  
  CONCLUSIONS
  When a single lead was used for the evaluation of QT prolongation, the results were not always similar to those using the lead which demonstrated the longest QT interval, and if only one lead is to be chosen, lead V3 or V4 should be selected.
authors.affiliation: Department of Medicine and Clinical Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan. sadanaga@kumamaoto-u.ac.jp
authors.forename: Tsuneaki
authors.initials: T
authors.lastname: Sadanaga
authors.forename: Fumiko
authors.initials: F
authors.lastname: Sadanaga
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yao
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Fujishima
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004562:Electrocardiography; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008133:Long QT Syndrome / Q000139:chemically induced / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D015995:Prevalence; D011619:Psychotropic Drugs / Q000009:adverse effects; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D011619:Psychotropic Drugs