Article

Effects of haemodialysis on maximum P wave duration and P wave dispersion.

First Department of Medicine, Medical and Health Science Center, University of Debrecen, Hungary.
Nephrology Dialysis Transplantation (impact factor: 3.4). 09/2002; 17(9):1634-8. pp.1634-8
Source: PubMed

ABSTRACT 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.
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.
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.
According to our results, ionic imbalance and dialysis itself may cause changes in P duration and dispersion simultaneously.

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Keywords

12-lead surface electrocardiogram
 
bicarbonate dialysate fluids
 
calipers
 
chronic haemodialysis
 
consecutive complexes
 
dispersion
 
end-stage renal failure
 
haemodialysis
 
Haemodialysis sessions
 
Ionic parameters
 
left atrial diameter larger
 
minimum P wave duration
 
non-diabetic patients
 
P dispersion
 
P wave dispersion
 
P wave duration
 
P wave durations
 
P wave interval
 
polysulfone dialysers
 
sessions
 

Zoltán Szabó