Jm. Lupoglazoff et al., Role of the right-to-left interatrial shunt in exercise tolerance of patients with paucisymptomatic Ebstein's anomaly., ARCH MAL C, 92(5), 1999, pp. 631-636
The aim of this study was to assess cardiorespiratory tolerance to exercise
in children with non-operated, paucisymptomatic and untreated forms of Ebs
tien's anomaly.
The authors undertook a prospective study in 11 children, mean age 9.6 year
s, who had lung function tests, cardiorespiratory exercise stress tests (bi
cycle ergometry N=8, treadmill N=3) and contrast echocardiography.
All parameters of spirometry were normal. Contrast echocardiography showed
a right-to-left interatrial shunt in 7 children (group 1) whereas the remai
ning 4 children had no shunt (group 2). The resting oxygen saturation was 9
7.4 +/- 2%, with no difference between the two groups. On the other hand, o
xygen saturation at peak VO2 (VO2 max) was 90 +/- 9.5%, significantly lower
in group 1 than in group 2 (85.7 +/- 2.2% vs 98.2 +/- 1.2%; p=0.03). In gr
oup 1, the VO2 max was correlated to oxygen saturation (r=0.98; p< 0.001, N
=6). The oxygen desaturation was correlated with presence of a right-to-lef
t interatrial shunt (p=0.01).
The reduced exercise tolerance of non-operated, paucisymptomatic children w
ith Ebstein's anomaly is due to a right-to-left interatrial shunt. In patie
nts with poor exercises tolerance, contrast echocardiography is advised for
the detection of these atrial shunts.