Impact of hemodialysis on comprehensive ventricular repolarization - Cardiac arrhythmia are one of the most important problems in haemodialysis patients. An important cause of the arrhythmias is inhomogenous myocardial repolarization. In this study, the ventricular repolarization parameters (QT, QTc, JT and JTc) and dispersions (d) of the parameters (QT-d, QTc-d, JT-d and JTc-d) were evaluated. Also, were recorded the right-sided lends (RV3-6) and posterior leads (V7-9) in addition to the standard 12 lead ECG to assess comprehensive ventricular repolarization. The leads were divided in three groups: Group A (Standard ECG leads), Group B (Right-sided leads) and Group C (All of the leads). Among the above mentioned parameters, only JT and JTc intervals decreased significantly in all groups. There was no significant difference between the groups in evaluation of the parameters. It was concluded that in assessment of ventricular repolarization, the most important ECG intervals may be JT and JTc intervals, and the standard 12 lead ECG record is sufficient in evaluation of ventricular repolarization in hemodialysis patients.