Patients with hereditary haemorrhagic telangiectasia (HHT)-related Pulmonary Arteriovenous Malformations (PAVMs). For all patients, the final diagnosis of certain HHT the diagnosis can be made depending on the presence of four criteria known as the Curaçao criteria: 1) Spontaneous recurrent epistaxis 2) Multiple telangiectasias in typical locations 3) Proven visceral Arteriovenous Malformations (AVM) (lung, liver, brain, spine) 4) First-degree family member with HHT. If conditions three or four are met, a patient has "definite HHT", while condition two is considered as "possible HHT". All patients had a molecular diagnosis and all follow-up clinical assessments were available in the database.

Annual clinical consultation with an Hereditary Haemorrhagic Telangiectasia (HHT) specialist and/or pneumologist and organ specialists when necessary (such as hepatologists, cardiologists and neurologists).

Explorations (contrast echography, chest Computed Tomography and treatments performed according to international guidelines.

TransCatheter Embolotherapy for each treatable Pulmonary Arteriovenous Malformations (PAVMs) and follow-up every 3 years.

Chest Computed Tomography (CT) every 6-12 months.

The presence of pulmonary arteriovenous malformations (PAVMs) (unique, multiple, disseminated or diffuse, the number of PAVMs and the largest feeding artery size) upon examination by CT could be correlated to the frequency of brain abscess and ischemic stroke in patients with hereditary haemorrhagic telangiectasia (HHT). These patients underwent a yearly CT scan to check for PAVM presence.