title: New definition and natural history of patients with diffuse pulmonary arteriovenous malformations: twenty-seven-year experience.
abstract: BACKGROUND
  Patients with diffuse pulmonary arteriovenous malformations (PAVM), a small but important subset of the PAVM population, have significant morbidity and mortality rates.
  
  
  METHODS
  Thirty-six patients (21 female and 15 male) with diffuse PAVM from a cohort of 821 consecutive patients with PAVM were evaluated. Diffuse PAVM were categorized angiographically: involvement of one or more segmental pulmonary arteries in one or both lungs. Hereditary hemorrhagic telangiectasia (HHT) status, gender, presence or absence of large (> or = 3-mm diameter artery) focal PAVM, oxygen saturations, complications including hemoptysis, years of follow-up, and survival were tabulated.
  
  
  RESULTS
  HHT was present in 29 of 36 patients (81%), and diffuse PAVM were more commonly bilateral (26 of 36 patients, 72%) than unilateral (10 of 36 patients, 28%) [p = 0.02]. Female gender was associated with bilateral diffuse PAVM (19 of 26 patients, 73%) [p = 0.01]. Focal PAVM were present in both groups but more commonly in patients with bilateral involvement (16 of 26 patients, 62%) [p = 0.02]. Initial oxygen saturations (pulse oximetry, standing) of patients with unilateral and bilateral diffuse PAVM were 87 +/- 7% and 79 +/- 8% (mean +/- SD), respectively (p = 0.02). The last or current values for patients with unilateral and bilateral involvement are 95 +/- 3% and 85 +/- 7%, respectively (p < 0.0001). Nine deaths occurred, and all were in patients with bilateral involvement. Deaths were due to hemoptysis of bronchial artery origin (n = 2), hemorrhage from duodenal ulcer (n = 1), spontaneous liver necrosis (n = 3), brain hemorrhage (n = 1), brain abscess (n = 1), and operative death during attempted lung transplant (n = 1).
  
  
  CONCLUSIONS
  Patients with diffuse PAVM are a high-risk group, and yearly follow-up is recommended.
authors.affiliation: Department of Respiratory Medicine, School of Medicine, Policlinic of Bari, Bari, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Pierucci
authors.forename: Joshua
authors.initials: J
authors.lastname: Murphy
authors.forename: Katharine J
authors.initials: KJ
authors.lastname: Henderson
authors.forename: Deborah A
authors.initials: DA
authors.lastname: Chyun
authors.forename: Robert I
authors.initials: RI
authors.lastname: White
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000792:Angiography; D001165:Arteriovenous Malformations / Q000175:diagnosis / Q000453:epidemiology* / Q000628:therapy; D006328:Cardiac Catheterization; D002648:Child; D002675:Child, Preschool; D004621:Embolization, Therapeutic / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D009017:Morbidity / Q000639:trends; D011379:Prognosis; D011651:Pulmonary Artery / Q000002:abnormalities* / Q000000981:diagnostic imaging; D011667:Pulmonary Veins / Q000002:abnormalities* / Q000000981:diagnostic imaging; D012189:Retrospective Studies; D015996:Survival Rate / Q000639:trends