Abstract

Pulmonary arteriovenous malformations (PAVMs are caused by an abnormal communication between the pulmonary arteries and veins. They may occur as an isolated anomaly or in association with hereditary hemorrhagic telangiectasia (HHT) (Rendu-Osler-Weber Syndrome). PAVMs occur in more than 30% of patients with HHT, are usually multiple, and occur most commonly in the lung bases. The larger malformations are associated with arterial hypoxemia, transient ischemic attacks, and stroke secondary to paradoxical embolism and cerebral abcess. Contrast echocardiography possesed the best attributes for a single screening test, however pulmonary angiography has still a gold standard for the diagnosis. Transcatheter coil embolization has replaced surgical resection as the treatment of choise; certainly effective for reducing right to left shunt, improving arterial hypoxemia, and increasing exercise capacity. In a conclusion, absence of dyspnea or normal resting oxygen saturation does not exclude clinically significant PAVMs and all patients with suspected PAVMs should therefore undergo detailed radiological screening.