Percutaneous embolization of pulmonary arteriovenous malformations in adult patient with Rendu-Osler-Weber: a case report.

Background: Hereditary haemorrhagic telangiectasia (HHT), or Rendu-Osler-Weber syndrome, is a rare genetic disorder characterized by the development of telangiectasias and arteriovenous malformations (AVMs) throughout the body. We present a case of percutaneous embolization of pulmonary AVMs in an adult patient. Case summary: A 26-year-old male patient with polycythaemia of unknown origin and a family history of secundum atrial septal defect underwent cardiac evaluation which revealed clubbing as a sign of peripheral cyanosis. Transthoracic echocardiography showed no intracardiac shunting, but further imaging revealed pulmonary AVMs in the lower lobe of the left lung. Magnetic resonance imaging of the brain detected vascular-ischaemic lesions, likely due to embolization through the pulmonary malformations. Right heart catheterization and pulmonary angiography confirmed the presence of large AVMs in the left lower pulmonary lobe. Percutaneous closure using Amplatzer devices was performed, followed by temporary anticoagulation therapy. Oxygen saturation improved and follow-up imaging confirmed successful closure of the AVMs. Genetic testing using whole exome sequencing identified a mutation in the ENG gene, confirming the diagnosis of HHT. Discussion: Our case highlights the importance of investigating both intra- and extracardiac shunting in patients with clinical features of right-to-left shunting. Arteriovenous malformations can serve as a pathway for paradoxical emboli, potentially leading to ischaemic brain events, and might cause pulmonary arterial hypertension. Screening for arteriovenous malformations in various organs and embolization of significant shunts are essential aspects of managing HHT. Genetic testing aids in confirming the diagnosis and guides family testing.