Abstract: Objective To investigate the changes of P wave dispersion (Pd) during the hemodialysis in uremia patients. Methods Twelve-lead ECGs were recorded before hemodialysis, 2 hours after beginning hemoidalysis and after one hemodialysis session, then Pd was analyzed. Prior to hemodialysis, the left atrial structure was measured with echocardiography. Blood urea nitrogen, creatinin and ionic parameters were checked during the study. Results Pd of the uremic patients undergoing hemodialyis was larger than that of the control group. There were significant increase in P wave maximum duration (Pmax) and Pd at the end of one hemodialysis session. The left atrial diameter of the uremic patients undergoing hemodialyis was larger than that of the control group. Conclusion Hemodialysis can lead to abnormal increase of Pmax and Pd. Measurement of Pd is helpful for prevention and treatment of atrial fibrillation in uremic patients undergoing hemodialysis.

Key words: Hemodialysis, Uremia