Effects of haemodialysis on maximum P wave duration and P wave dispersion.
BACKGROUND
Analysing a 12-lead surface electrocardiogram (ECG), the inter-lead variability of the P wave interval, i.e. P wave dispersion, is defined as the difference between the maximum and the minimum P wave duration. Our aim was to assess the effect of haemodialysis on P wave duration and dispersion in non-diabetic patients with end-stage renal failure on chronic haemodialysis.


METHODS
Twenty-eight patients (14 men and 14 women, mean age 58+/-16 years, average duration of dialysis 4.5+/-2.8 years) were examined. Prior to haemodialysis, echocardiography (M-mode and two-dimensional) was performed. Haemodialysis sessions were carried out with polysulfone dialysers and bicarbonate dialysate fluids. Twelve-lead ECGs were recorded at the beginning, 15 and 30 min after starting dialysis, at the end, and 2 h after completion of each session. Ionic parameters were checked during the study. P wave durations were measured with calipers in three consecutive complexes of each lead by one observer.


RESULTS
P maximum was 58+/-16 ms at the beginning, and showed an increase by the end of dialysis to 98+/-8.9 ms (P<0.0001). Pre-dialysis P dispersion was 23+/-10 ms and increased to 41+/-16 ms by the end of the sessions (P<0.0001). In patients with a left atrial diameter larger than 45 mm, P dispersion increased from 23+/-11 to 53+/-10 ms (P<0.0003) by the end of the sessions.


CONCLUSIONS
According to our results, ionic imbalance and dialysis itself may cause changes in P duration and dispersion simultaneously.
First Department of Medicine, Medical and Health Science Center, University of Debrecen, Hungary.
Zoltán
Z
Szabó
György
G
Kakuk
Tibor
T
Fülöp
János
J
Mátyus
József
J
Balla
István
I
Kárpáti
Attila
A
Juhász
Csaba
C
Kun
Zsolt
Z
Karányi
István
I
Lorincz
D001281:Atrial Fibrillation / Q000453:epidemiology; D001794:Blood Pressure / Q000502:physiology*; D004562:Electrocardiography; D005260:Female; D006321:Heart / Q000503:physiopathology*; D006325:Heart Atria / Q000473:pathology; D006331:Heart Diseases / Q000150:complications / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D006435:Renal Dialysis; D013997:Time Factors