Measurement of the QT interval.
D001145:Arrhythmias, Cardiac / Q000503:physiopathology*; D004562:Electrocardiography / Q000379:methods*; D006329:Heart Conduction System / Q000503:physiopathology*; D006352:Heart Ventricles / Q000503:physiopathology; D006801:Humans; D008133:Long QT Syndrome / Q000503:physiopathology*; D009203:Myocardial Infarction / Q000503:physiopathology*