Background: Hereditary hemorrhagic telangiectasia (HHT)
is a dominantly inherited disease with a high prevalence of pulmonary
arteriovenous malformations (PAVMs). The first symptom of HHT may be
stroke or fatal hemoptysis associated with the presence of PAVM.
Objective: To evaluate different screening methods applied
for the identification of PAVMs.
Subjects: HHT patients with
positive findings on contrast echocardiography (CE) who participated in
a screening investigation and underwent pulmonary angiography
Methods: Different screening methods were
evaluated against the results of PA. In a group of patients with
positive findings on CE, we compared results of PA with the following:
severity of dyspnea; results of pulse oximetry arterial oxygen
saturation (Sao2) supine and upright; supine
Pao2 in room air and while breathing 100%
oxygen; size of arteriovenous shunt in supine position; chest
radiograph; and intensity of contrast at CE.
PA was performed in 25 HHT patients with positive findings on CE, 15 of
whom had PAVM. Embolization therapy was recommended in 12 patients, and
3 patients had small PAVMs not accessible for therapy. In 10 patients,
PAVM could not be demonstrated at PA. The sensitivity and specificity
calculated for the screening procedures are as follows: 53% and 90%,
respectively, for Sao2; 60% and 100%,
respectively, for chest radiograph; 73% and 80%, respectively, for
Pao2 in room air; 100% and 40%, respectively,
for Pao2 breathing 100% oxygen; and 64% and
80%, respectively, for shunt measurement.
Conclusion: Initial screening with CE followed by
measurement of Pao2 while breathing 100%
oxygen seemed to be the best screening procedure for identification of
patients with PAVM. Screening with chest radiograph and pulse oximetry
was shown to be insufficient.