title: Treated pulmonary arteriovenous malformations: patterns of persistence and associated retreatment success.
abstract: OBJECTIVE
  To determine the relative frequencies of persistence patterns in treated pulmonary arteriovenous malformations (PAVMs) and to assess whether there is a difference in retreatment outcomes between PAVMs persisting via recanalization and those persisting via reperfusion.
  
  
  METHODS
  Between May 2003 and May 2011, 23 patients (10 male, 13 female; mean age, 44 years ± 18 [standard deviation]; age range, 12-72 years) who had PAVM embolization, persistence by computed tomography (CT), and a follow-up pulmonary arteriogram were included. This retrospective study was approved by the institutional review board and was fully HIPAA compliant. PAVMs were categorized as having recanalization, defined as persistence maintained by flow through a previously placed coil nest; reperfusion, defined as persistence through small feeders from adjacent normal pulmonary arteries; or incomplete treatment. Fifty-three persistent PAVMs were characterized; 38 of which had postretreatment CT data (median follow-up, 1 year). The retreatment success rate, defined by sac shrinkage on CT images, was assessed.
  
  
  RESULTS
  Recanalization was the most common pattern, occurring in 91% (n = 48) of 53 PAVMs. Pulmonary-to-pulmonary reperfusion occurred in 24% (n = 13) of 53 PAVMs. Angioarchitecture, coil-sac distance, coil number, and feeder diameter did not significantly differ between recanalized and reperfused PAVMs. There was a significant (P = .014) difference in retreatment success; retreatment was successful in 84% (n = 27) of 32 recanalized PAVMs but only 44% (n = 4) of nine reperfused PAVMs.
  
  
  CONCLUSIONS
  Recanalization through previously placed coils is the most common pattern of PAVM persistence and responds best to retreatment. Pulmonary-to-pulmonary reperfusion is less common and more difficult to re-treat successfully. Online supplemental material is available for this article.
authors.affiliation: From the Department of Radiology, Division of Interventional Radiology (C.S.W., S.O.T.), and Department of Medicine, Division of Translational Medicine and Human Genetics (R.E.P.), University of Pennsylvania Medical Center, Hospital of the University of Pennsylvania, 1 Silverstein, 3400 Spruce St, Philadelphia, PA 19104; and Department of Medicine, Division of Biostatistics, Drexel University School of Medicine, Philadelphia, Pa (J.L.C.).
authors.forename: Catherine S
authors.initials: CS
authors.lastname: Woodward
authors.forename: Reed E
authors.initials: RE
authors.lastname: Pyeritz
authors.forename: Jessie L
authors.initials: JL
authors.lastname: Chittams
authors.forename: Scott O
authors.initials: SO
authors.lastname: Trerotola
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000792:Angiography; D001165:Arteriovenous Malformations / Q000000981:diagnostic imaging* / Q000628:therapy*; D002648:Child; D004621:Embolization, Therapeutic; D005260:Female; D006801:Humans; D008171:Lung Diseases / Q000000981:diagnostic imaging / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D019233:Retreatment; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome