Comparison of determinations of left atrial volume by the biplane area-length and Simpson's methods using 64-slice computed tomography.
OBJECTIVE
There is increasing evidence that left atrial (LA) size is an important predictor of adverse cardiovascular outcomes such as atrial fibrillation, stroke, and congestive heart failure. The aim of this study was to determine whether there is a difference in results of quantification of LA volume by the area-length and Simpson's methods using multislice computed tomography (MSCT).


RESULTS
The study population consisted of 51 patients with sinus rhythm (sinus group) and 20 patients with atrial fibrillation (af group) clinically indicated for MSCT angiography for evaluation of coronary arteries. Maximum LA volume, obtained at end-systole from the phase immediately preceding mitral valve opening, was measured using the area-length and Simpson's methods. In the sinus group, the mean LA volumes, indexed to body surface area, were 48.4+/-17.9 ml/m(2) with the area-length method and 48.3+/-17.0 ml/m(2) with the Simpson's method. In the af group, the mean indexed LA volumes with the area-length method and the Simposon's method were 91.5+/-47.5 ml/m(2) and 90.3+/-45.9 ml/m(2), respectively. LA volumes calculated by the area-length method exhibited a strong linear relationship and agreement with those calculated using Simpson's method in both the groups (sinus group: r=0.99, P<0.0001, af group: r=0.99, P<0.0001).


CONCLUSIONS
The area-length method is a simple and reproducible means of assessment of LA volume. Standardization of LA volume assessment using MSCT is important for serial follow-up and meaningful communication of results of testing among institutions and physicians.
Takagi
Yasuhiro
Y
Department of Internal Medicine, Osaka City University Graduate School of Medicine, 1-4-3 Asahi-machi, Abeno-ku, Osaka 545-8585, Japan.
Ehara
Shoichi
S
Okuyama
Takuhiro
T
Shirai
Nobuyuki
N
Yamashita
Hajime
H
Sugioka
Kenichi
K
Kitamura
Hitoe
H
Ujino
Keiji
K
Hozumi
Takeshi
T
Yoshiyama
Minoru
M
D000368:Aged; D001281:Atrial Fibrillation / Q000000981:diagnostic imaging; D003327:Coronary Disease / Q000000981:diagnostic imaging; D004452:Echocardiography; D005260:Female; D006325:Heart Atria / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D006352:Heart Ventricles / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D008875:Middle Aged; D009929:Organ Size; D015203:Reproducibility of Results; D014057:Tomography, X-Ray Computed / Q000379:methods*