4:12 PM Abstract No. 109 Proximal versus distal embolization technique for treatment of reperfused pulmonary arteriovenous malformations

Abstract

To compare the success of proximal versus distal embolization technique for treatment of previously embolized, recurrent pulmonary arteriovenous malformations (rPAVMs). Between July 2007 and July 2017, 16 consecutive patients underwent embolization of 41 previously treated rPAVMs within a single academic medical center with imaging follow-up. At the time of treatment, the mechanism of reperfusion (through or around the existing embolic) was characterized. Repeat embolization was performed either by embolizing proximal to or around the existing embolic (proximal embolization technique) or by embolizing distal to the existing embolic (distal embolization technique). Follow-up imaging was reviewed to determine the presence or absence of persistent perfusion of the rPAVM, which was defined as contrast opacification of the sac and/or draining vein. Persistent perfusion rates of the embolization techniques were compared. Mean patient age was 55.4 years (range, 38 to 75 years) and 68.8% were female. 13 patients (81.2%) had definite hereditary hemorrhagic telangiectasia (HHT). Of the 41 previously embolized PAVMs, 28 had reperfused through the existing embolic, 4 had reperfused around the existing embolic, and 9 had reperfused by both mechanisms. Eight of the 41 rPAVMs were treated with distal embolization technique, and 33 were treated with proximal embolization technique. Overall persistent perfusion rate of the re-embolized rPAVMs was 53.7% at median follow-up time of 280 days. Persistent perfusion was significantly less likely with distal embolization technique (1/8, 12.5%) than with proximal embolization technique (21/33, 63.6%) (p = 0.016). Recurrent PAVMs are difficult to treat, with high rates of persistent perfusion following repeat embolization. Embolization distal to the existing embolic is significantly more likely to produce durable occlusion than embolization proximal to or around the existing embolic.