Increases in P-wave duration and dispersion after hemodialysis are totally (or partially) due to the procedure-induced alleviation of the body fluid overload: a hypothesis with strong experimental support.

Increases in the P-wave duration (P-du) and P-wave dispersion (P-d) following hemodialysis (HD) are attributed to changes in the electrolytic milieu with HD, or are considered to be due to an unknown mechanism. Such changes are thought to be proarrhythmic, and thus have potential clinical implications. Increase in the amplitude of QRS complexes following HD has been amply documented in the literature. Also, recent work linking attenuation/augmentation of amplitude of QRS and P-wave complexes in patients with increase/subsequent decrease weights due to anasarca peripheral edema/and its alleviation, or before/after hemodialysis (HD) suggests that the increase in the P-du and P-d after HD may be totally (or partially) mediated by the alleviation of the fluid overload by the procedure. This is supported by the decrease/increase in the QRS duration noted with anasarca/and its alleviation. To further clarify this issue, and prove or refute the above hypothesis, it is recommended that correlations of changes in the P-du and P-d with the loss of weight or net fluid dialyzed are carried out, in addition to the traditional considerations of electrolytic alterations after HD.