Angiographic features of pulmonary arteriovenous malformations: a new imaging classification system, BRAND, to guide...

To introduce a new classification system for pulmonary arteriovenous malformations (PAVMs) based on the BRanches, ANgles and Diameter of the feeding artery (BRAND), which is intended provide a better understanding of the vascular structure of PAVMs and facilitate the selection of therapeutic strategies for embolisation.

Twenty-one patients with PAVMs from 2005 to 2020 were reviewed retrospectively. According to angiographic morphology, classified the PAVMs using the BRAND classification.

A total of 41 PAVMs were treated with transcatheter embolisation. Based on the BRAND classification, there were four branches (9.8%), four acute angles (9.8%), and 32 occlusion sites >4 mm in diameter (78%). A total of 30 PAVMs (73.2%) were treated with occluders and plugs while the rest were embolised with coils (26.8%). Immediate technical success was achieved in all patients. In feeding arteries with acute angles, balloon-assisted tracking and trans-septal puncture techniques were used to facilitate the advancement of delivery systems. All origins of branches were preserved. Mean SaO₂ increased significantly from 79.5 ± 7.5% before embolisation to 92 ± 5.3% after embolisation (p<0.05). During a median follow-up of 5.4 years, two patients (9.5%) developed new PAVMs and required a second procedure. One patient (4.8%) underwent repeat embolisation due to the reperfusion of previously embolised PAVMs with coils.

BRAND classification is well suited to address the challenging feeding arteries of PAVMs and allow precise placement of the delivery system, leading to minimal procedural risk and high success rates.