Effect of age and heart rate on atrial mechanical function assessed by Doppler tissue imaging in healthy individuals.
BACKGROUND
The potential usefulness of Doppler tissue imaging (DTI) to assess atrial mechanical function in cardiac disease has been demonstrated. However, there are few reports on normal values of atrial function by DTI analysis.


METHODS
Echocardiography with color-coded DTI was performed in 131 healthy control subjects. The peak atrial contraction velocity (V(A)) and the timing of mechanical events were assessed offline at the left atrial (LA) and right atrial (RA) free wall and interatrial septum.


RESULTS
V(A) was higher in the RA (9.0 +/- 2.6 cm/s) than the LA (7.5 +/- 2.4 cm/s, P < .001), and both sites were higher than the interatrial septum (5.6 +/- 1.3 cm/s, both P < .001). The interatrial delay was 24 +/- 21 milliseconds. V(A) at the LA was higher in the participants aged 60 years or older than those who were younger than 60 years (8.1 +/- 2.7 vs 6.7 +/- 1.4 cm/s, P < .001), as was the velocity at the RA (9.6 +/- 2.8 vs 8.0 +/- 2.1 cm/s, P < .01). V(A) at the LA was higher in the participants with heart rate of 60/min or higher than those with lower heart rate (7.9 +/- 2.5 vs 6.8 +/- 1.8 cm/s, P < .05). Sex difference had no effect on V(A) and timings of atrial events.


CONCLUSIONS
Assessment of atrial mechanical function by DTI is feasible in healthy individuals. The V(A) is the highest at the RA, followed by LA, and the lowest at the interatrial septum. Older age and faster heart rate seems to augment V(A) in the atrial walls.
Zhang
Qing
Q
Division of Cardiology, Department of Medicine and Therapeutics, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong SAR.
Kum
Leo C C
LC
Lee
Pui-Wai
PW
Lam
Yat-Yin
YY
Wu
Eugene B
EB
Lin
Hong
H
Yip
Gabriel Wai-Kwok
GW
Wu
LiWen
L
Yu
Cheuk-Man
CM
D000375:Aging / Q000502:physiology*; D016275:Atrial Function / Q000502:physiology*; D015150:Echocardiography, Doppler / Q000379:methods*; D005240:Feasibility Studies; D005260:Female; D006325:Heart Atria / Q000000981:diagnostic imaging*; D006339:Heart Rate / Q000502:physiology*; D006352:Heart Ventricles / Q000000981:diagnostic imaging*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016276:Ventricular Function; D016277:Ventricular Function, Left