H. Oxhoj et al., Screening for pulmonary arteriovenous malformations - Contrast echocardiography versus pulse oximetry, SC CARDIOVA, 34(3), 2000, pp. 281-285
Pulmonary arteriovenous malformations (PAVM) cause right-to-left shunt and
imply risk of paradoxical embolism and cerebral abscess. These complication
s can be prevented by appropriate treatment. Detection of PAVMs is therefor
e important, so simple and reliable screening methods are needed for this p
urpose. The aim of this investigation was to compare pulse oximetry and con
trast echocardiography as screening tools for detection of pulmonary arteri
ovenous malformations. Eighty-five hereditary haemorrhagic telangiectasia (
HHT) patients and first-degree relatives identified in a comprehensive stud
y of HHT-families in the county of Funen, Denmark, were investigated. Stand
ing and supine pulse oximetry in room air was performed in all subjects, an
d in subjects with symptoms and/or abnormal pulse oximetry in room air, sup
ine pulse oximetry breathing 100% oxygen was also performed. Transthoracic
echocardiography with intravenous injection of echo contrast was performed
in all subjects. Outcome measures were oxygen saturation change >2% units o
n changing body position and echo contrast observed in the left-sided heart
chambers. Positive contrast echocardiography indicating the presence of PA
VM was found in 47 subjects, whereas pulse oximetry was abnormal in only 16
. The results strongly suggest that contrast echocardiography is a more sen
sitive screening tool for PAVMs than pulse oximetry.