Relationship between P-wave dispersion and effective hemodialysis in chronic hemodialysis patients.

OBJECTIVE To investigate whether or not P-wave dispersion (PWD) can be used as a good indicator of effective hemodialysis. SUBJECTS AND METHODS The study included 35 patients (20 males, 15 females, mean age 61 +/- 10 years) who regularly received hemodialysis treatment for chronic renal failure. Following hemodialysis, the patients whose hemodynamic parameters were preserved and who reached dry body weight were included. Twelve-lead resting electrocardiogram (ECG) at a speed of 25-50 mm/s, the value of total body fluid (TBF) and bioelectric impedance using bipedal bioelectric impedance equipment were obtained before and immediately after hemodialysis. Blood samples were also taken for the assessment of blood electrolytes, urea and creatinine. PWD was defined as the difference between the maximum and minimum P-wave duration calculated on a standard 12-lead ECG before and after dialysis. RESULTS The following parameters were obtained before and after hemodialysis: blood pressure 132 +/- 21 vs. 130 +/- 10 mm Hg (p > 0.05), TBF 33.9 +/- 6 vs. 32 +/- 5.6 liters (p = 0.001), impedance 499 +/- 110 vs. 596 +/- 136 Omega (p = 0.001), P-max 103.1 +/- 8.9 vs. 106.3 +/- 12.7 ms (p > 0.05), P-min 70.2 +/- 11 vs. 72.5 +/- 7.9 ms (p > 0.05), PWD 32.2 +/- 11.9 vs. 33.8 +/- 13.4 ms (p > 0.05). Although statistically significant decreases were observed in urea and creatinine levels after hemodialysis, no such changes were observed in blood electrolytes. CONCLUSION The P-max and PWD did not change significantly after hemodialysis, hence these two parameters can be used as an indicator of effective hemodialysis.