Signal-averaged P wave duration and the dimensions of the atria.
BACKGROUND
Delay of atrial electrical conduction measured as prolonged signal-averaged P wave duration (SAPWD) could be due to atrial enlargement. Here, we aimed to compare different atrial size parameters obtained from echocardiography with the SAPWD measured with a signal-averaged electrocardiogram (SAECG).


METHODS
In 74 patients scheduled for elective echocardiography, an SAECG was recorded directly after the echocardiogram. We measured the SAPWD and registered clinical characteristics. The correlation between the SAPWD and the left atrial diameter (LAD), left atrial volume (LAV), right atrial volume (RAV), and total atrial volume (TAV) was analyzed by linear regression analyses. The effect of concomitant risk factors on TAV and the SAPWD was examined.


RESULTS
Linear regression analysis showed that the correlation between the SAPWD and the LAD was significant (R(2)= 0.11, P = 0.03). However, LAV (R(2)= 0.15, P = 0.009), RAV (R(2)= 0.27, P = 0.0003), and TAV (R(2)= 0.37, P < 0.0001) were more strongly correlated to the SAPWD. The TAV and the SAPWD were not significantly associated with coexisting risk factors.


CONCLUSIONS
The SAPWD is significantly correlated to the atrial size; most strongly to the TAV. The size of the right atrium, with the sinus node area, appears to affect the SAPWD.
Dixen
Ulrik
U
Department of Cardiology, University Hospital of Hvidovre, Copenhagen, Denmark. ulrikdixen@mail.dk
Joens
Christian
C
Rasmussen
Bo V
BV
Parner
Jan
J
Jensen
Gorm B
GB
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004452:Echocardiography; D004562:Electrocardiography; D005260:Female; D006325:Heart Atria / Q000000981:diagnostic imaging / Q000503:physiopathology*; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D012307:Risk Factors