Hemodiafiltration and hemodialysis differently affect P wave duration and dispersion on the surface electrocardiogram.

AIM: The incidence of atrial fibrillation is increased during hemodialysis (HD); however, the effects of hemodiafiltration (HDF) on atrial arrhythmias have not been evaluated. The prolongation of the P wave and P dispersion (Pd) can predict atrial arrhythmias. METHODS: Data from 30 patients receiving HDF over a period of 3 months were collected; the same group of patients was then evaluated during treatment with conventional HD for at least another 3 months. Electrolyte values were obtained, and surface electrocardiograms (ECG), echocardiography, and Holter ECGs were performed. RESULTS: The duration of the P wave and Pd increased significantly during HD. The left atrial diameter decreased significantly only during HDF. During HDF, the left atrial cross diameter measured at the beginning of the session was positively correlated with the incidence of supraventricular premature beats (p = 0.011, r = 0.4556). The decrease in left atrial diameter during HDF was negatively correlated with the incidence of supraventricular premature beats (p = 0.016, r = -0.43). During HDF, the changes in sodium and Pd were significantly positively correlated (p < 0.05, r = 0.478). During HD, the changes in ionized calcium levels and Pd were positively correlated (p < 0.05, r = 0.377). CONCLUSION: Our results suggest that HDF has a more beneficial effect on P wave duration and Pd than HD. The alterations in the ECG markers may be the result of the simultaneous occurrence of certain electrolyte imbalances and renal replacement methods.

Hemodiafiltration beneficially affects QT interval duration and dispersion compared to hemodialysis.

BACKGROUND/AIMS: The prolongation of the QT interval and dispersion could predict ventricular arrhythmias. It is not yet established whether there is a difference between the effects of hemodialysis and hemodiafiltration on QT interval duration and dispersion. METHODS: Data of thirty patients was investigated while they were receiving hemodiafiltration over a period of 3 months; then the same group of patients was evaluated during treatment with conventional hemodialysis for at least another 3 months. Ionic parameters and surface electrocardiograms (ECG) were analyzed five times during each session, and 2D, M-mode echocardiography and Holter ECGs were performed to acquire additional information. RESULTS: QT interval duration (QTmax) and dispersion (QTd) showed a significant increase during hemodialysis, but not during hemodiafiltration. QTmax was 388.66 ± 31.81 ms at the beginning of hemodialysis and increased to 400.66 ± 39.12 ms even at the 30th minute (p < 0.05). QTd was found to be 31.33 ± 10.08 ms before the commencement of hemodialysis with the largest prolongation being seen at the 240th minute (51.33 ± 14.56 ms, p < 0.05). The occurrence of ventricular premature beats was significantly higher during hemodialysis (p = 0.018). The left atrial diameter significantly decreased at the end of hemodiafiltration (at the beginning 45.1 ± 5.25 mm, at the end 40.77 ± 5.76 mm; p < 0.05). CONCLUSION: Our results suggest a beneficial effect of hemodiafiltration on the studied electrocardiographic parameters compared to hemodialysis. The larger decrease in the left atrial diameter suggests a more efficient intracardiac volume-decreasing potential of hemodiafiltration.