13th Annual Global Embolization Symposium & Technologies
Purpose : To evaluate intermediate-term success of embolotherapy for pulmonary arteriovenous malformations (PAVMs), and determine the factors that predict durable occlusion.
Material and Methods : 101 patients with 269 native PAVMs undergoing first embolization between 2008–2018 were selected for IRB-approved retrospective evaluation. 67 (66%) patients were female and mean age was 44 years (range, 10-87). 82 patients had a diagnosis of definite hereditary hemorrhagic telangiectasia (HHT). Treatment was considered for feeding arteries >2 mm. PAVMs were characterized as having simple (1 feeding artery) or complex (>2 feeding vessels) angioarchitecture. Embolization technique was characterized as occlusion of i) proximal feeding artery (PFA) (>1 cm from nidus), ii) distal feeding artery (DFA) (within 1 cm of nidus), iii) nidus only (NO), or iv) nidus plus distal feeding artery (NFA). Embolic materials included coils, plugs, or both in 228, 20, and 21 PAVMs, respectively. Technical success was defined as lack of flow on angiography at the time of embolization. Treatment success was defined as absence of contrast opacification of the sac and/or draining vein on follow-up CT angiography.
Results : Technical success was achieved in all 269 PAVMs. Overall treatment success was 236/269 (87.7%) at a mean follow-up of 548 days (range, 32–3091). Success improved over time, with a rate of 179/189 (94.7%) from 2014–2018 vs. 54/80 (71.3%) from 2008–2013 (P<0.001). Success rates were 165/179 (92.2%) for simple PAVMs vs. 71/90 (78.9%) for complex PAVMs (P=0.002). Overall success rate by technique was 87.5% (7/8) for PFA, 83.9% (120/143) for DFA, 57.1% (4/7) for NO, and 94.6% (105/111) for NFA. For simple AVMs, success was significantly higher for NFA technique (59/59, 100%) than DFA technique (97/110, 88.2%) (p=0.005). For complex AVMs, success was higher for NFA technique (46/52, 88.5%) than either DFA technique (23/33, 69.7%) or NO technique (0/3, 0%). There was no statistically significant difference in success with respect to HHT status, feeding artery diameter, type of embolic material, or number of coils deployed. No coil migrations or major complications were observed.
Conclusions : Our 10-year experience with embolization of 269 native PAVMs suggests that success rates have improved over time, but that complex AVMs continue to pose a challenge. For both simple and complex PAVMs, embolization of both the nidus and the feeding artery leads to more durable occlusion than embolization of the feeding artery alone.