Pulmonary Arteriovenous Malformations: What the Interventional Radiologist Should Know

Abstract

Pulmonary arteriovenous malformations (PAVMs) are abnormal connections between the pulmonary artery and pulmonary vein bypassing the normal capillary bed causing a right-to-left shunt. The majority (80–90%) of PAVMs are associated with hereditary hemorrhagic telangiectasia (HHT). PAVMs may be asymptomatic or present with symptoms of hypoxia, shortness of breath, migraines, sequelae of paradoxical embolization, or rupture. Transcatheter embolization has become the standard of care. This article will review the clinical presentation, workup, genetics, imaging findings, embolization, complications, and follow-up for patients with PAVMs.

Large pulmonary arteriovenous malformation lost to follow-up with 10 years of asymptomatic interval growth: A case report

“…In the general population, clinically significant PAVMs are uncommon, with a prevalence of 1 per 2600 individuals found in a retrospective study of patients undergoing lung cancer screening [ 3 ]. Up to 85% of PAVM cases are associated with hereditary hemorrhagic telangiectasia, resulting from abnormal angiogenesis throughout the body [ 1 , 8 ]. About 30%-50% of HHT patients have PAVMs, but 10%-20% of PAVM cases lack signs of HHT or other systemic disease.…”

“…PAVMs should be suspected in patients with a personal or family history of HHT or signs of right-to-left shunting such as digital clubbing, cyanosis, or dyspnea on exertion. Chest X-ray classically shows a round, well-circumscribed, soft tissue density that may be associated with enlarged vessels [ 1 , 8 , 10 , 14 ]. Noninvasive options to detect right-to-left shunting include arterial blood gases with PaO2 < 85 mm Hg suggesting a significant shunt (> 5%) is likely.…”

“…The first-line treatment for PAVMs is embolization which has a high success rate (95%-100%) and low rate of complications (most commonly pleurisy) [ 8 , 13 , 14 ]. Embolization is indicated in all symptomatic patients and asymptomatic patients with feeding vessels larger than 2-3 mm [ 8 , 9 , 17 ]. In patients who are not candidates for embolization therapy, local resection or segmentectomy may be performed.…”

“…When symptomatic, patients often present with signs of right-to-left shunting including dyspnea, cyanosis, and digital clubbing, but severe cases may present with hemoptysis and hemorrhagic shock from PAVM rupture [ [5] , [6] , [7] ]. Treatment depends on the size and position of the lesion with endovascular embolization indicated as first-line treatment in all symptomatic PAVMs and for asymptomatic lesions with feeding vessels larger than 2-3 mm [ 3 , 8 ].…”

“…Even large PAVMs may be asymptomatic despite their increased risk of rupture, and close surveillance is recommended to monitor for the development of symptomatic disease or enlargement [ 1 , [5] , [6] , [7] , [8] ]. Here we present a case of a large, asymptomatic PAVM found incidentally in a patient without HHT who was lost to follow-up and presented 10 years later with acute respiratory failure and interval increase in lesion size.…”