Computational analysis of uremia effects on ventricular action potential

Patients suffering from renal failure often develop cardiac disturbances. In order to give a mathematical description of the effects of uremia on cardiac cellular excitability, the Ten Tusscherpsilas model (2006) of human ventricular myocyte has been modified to incorporate the known effects of uremia on several ionic currents. The model was applied to study the effects of uremia and of the dialysis therapy on action potential duration (APD) and its restitution in response to the S1-S2 protocol. An altered transient repolarization and a shorter APD were found in the uremic myocyte. The APD restitution was also affected by uremia. At the end of dialysis, action potentials obtained after short diastolic intervals were characterized by the absence of the plateau phase. This could contribute to electrical inhomogeneity and explain the increase of arrhythmia occurrence often clinically observed in the last stage of the dialysis session.