Pulmonary arteriovenous - Malformations screening procedures and pulmonary angiography in patients with hereditary hemorrhagic telangiectasia

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. Setting: Odense University Hospital. Subjects: HHT patients with positive findings on contrast echocardiography (CE) who participated in a screening investigation and underwent pulmonary angiography (PA), 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 (Sao(2)) supine and upright; supine Pao, in room air and while breathing 100% oxygen; size of arteriovenous shunt in supine position; chest radiograph; and intensity of contrast at CE, Results: 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 Sao,; 60% and 100%, respectively, for chest radiograph; 73% and 80%, respectively, for Pao, in room air; 100% and 40%, respectively, for Pao, breathing 100% oxygen; and 64% and 80%, respectively, for shunt measurement. Conclusion: Initial screening with CE followed by measurement of Pao, 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.