Abstract No. 220 Embolotherapy for Pulmonary Arteriovenous Malformations: A Single-Center Experience

Pulmonary arteriovenous malformations (PAVMs) are abnormal direct connections between pulmonary arteries and veins. Embolization is the preferred treatment for PAVMs; however, there is ongoing debate regarding the best approach to ensure long-term occlusion. This study investigates which techniques or characteristics correlate with treatment failure. Review of PAVM embolization procedures between September 2014 and December 2022 at a hereditary hemorrhagic telangiectasia (HHT) center of excellence was performed. PAVMs undergoing initial treatment with follow up cross-sectional imaging were included. Data was collected for PAVM angioarchitecture, embolization of the nidus, embolic material, technical success, and recanalization/reperfusion on follow-up cross sectional imaging. Categorical variables were compared using chi-square test and continuous variables using independent samples t-test. The final cohort included 93 PAVMs in 57 patients (median age 47, 65% female). The majority of patients had HHT (49/57, 86%). Most PAVMs were simple (77/93, 82%) and saccular (68/93, 73%). The nidus was treated in 63/93 (68%), and more often with simple PAVMs (56/77, 73%) than complex PAVMs (7/16, 44%), which was statistically significant (P=0.03). Treatment was performed with coils (64/93, 69%), coils and plugs (23/93, 25%), plugs alone (5/93, 5%), or Onyx (1/93, 1%). Complex PAVMs were more likely to be treated with a plug (10/16, 62%) than simple PAVMS (18/77, 23%), which was statistically significant (P< 0.005). Treatment technical success was achieved in 85/93 (91%) of PAVMs after the index procedure, and 90/93 (97%) after all subsequent procedures, including 3 that developed delayed thrombosis on follow-up. Recanalization occurred in 2/93 (2%) after 3 and 35 months, and reperfusion occurred in 1/93 (1%) after 2.5 months. Mean follow-up was 30 ± 26 months. Of the 11 that had primary technical failure or recanalization/reperfusion, statistically significant associations were seen with complex angioarchitecture (5/11, 45%, P=0.02) and fibered coils (7/11, 63%, P=0.05). Also in this subgroup, mean feeding artery diameter and sac diameter were bigger (4.5 vs. 3.9 mm and 16 vs. 13.3 mm, respectively), but not statistically significant. No major procedural or post-procedural complications occurred. Embolization of simple and complex PAVMs can result in high rates of technical success. Complex PAVMs may be more difficult to treat the entire nidus, and may have higher rates of technical failure or reperfusion/recanalization.