title: A longitudinal study of the course of asymptomatic antibody-mediated rejection in heart transplantation.
abstract: BACKGROUND
  Growing evidence suggests worse cardiac allograft vasculopathy and mortality in patients with asymptomatic antibody-mediated rejection (AMR). Debate continues about whether therapeutic intervention is warranted to avoid adverse outcomes. In this study we examine the course of individual episodes of untreated asymptomatic AMR on follow-up endomyocardial biopsy (EMB).
  
  
  METHODS
  The U.T.A.H. Cardiac Transplant Program database was queried for transplant recipients between 1985 and 2009 who survived beyond 1 year and had at least 1 episode of lone AMR with a follow-up EMB. All EMBs were screened for AMR by immunofluorescence and graded for severity. Data were analyzed based on time from transplant (early, ≤12 months; late, >12 months).
  
  
  RESULTS
  Nine hundred fifty-eight patients with a total of 15,448 biopsies qualified for the study. Average age at transplant was 46.7 years; 13% of the patients were female. Within the first year post-transplant, asymptomatic AMR was diagnosed in 13.6% of biopsies compared with 5.2% beyond 1 year. AMR resolved in 65% (early) vs 75% (late) on follow-up EMB. More severe AMR was less likely to improve regardless of time from transplant. Furthermore, after an episode of AMR had resolved, the recurrence rate at 3, 6 and 12 months was 44%, 50.1% and 56.2%, respectively.
  
  
  CONCLUSIONS
  The incidence of AMR is higher in the first year post-transplant and the likelihood of resolution is less on follow-up EMB, especially when more severe. A small but significant number of cases became worse or did not change. These new findings may be helpful in planning future studies that test whether therapeutic interventions on asymptomatic AMR favorably impact outcomes.
authors.affiliation: Intermountain Medical Center and Intermountain Healthcare, Salt Lake City, Utah, USA. akfoury@imail.org
authors.forename: Abdallah G
authors.initials: AG
authors.lastname: Kfoury
authors.forename: Gregory L
authors.initials: GL
authors.lastname: Snow
authors.forename: Deborah
authors.initials: D
authors.lastname: Budge
authors.forename: Rami A
authors.initials: RA
authors.lastname: Alharethi
authors.forename: Josef
authors.initials: J
authors.lastname: Stehlik
authors.forename: Melanie D
authors.initials: MD
authors.lastname: Everitt
authors.forename: Dylan V
authors.initials: DV
authors.lastname: Miller
authors.forename: Stavros G
authors.initials: SG
authors.lastname: Drakos
authors.forename: Bruce B
authors.initials: BB
authors.lastname: Reid
authors.forename: M Patricia
authors.initials: MP
authors.lastname: Revelo
authors.forename: Edward M
authors.initials: EM
authors.lastname: Gilbert
authors.forename: Craig H
authors.initials: CH
authors.lastname: Selzman
authors.forename: Feras M
authors.initials: FM
authors.lastname: Bader
authors.forename: Jennifer J
authors.initials: JJ
authors.lastname: Connelly
authors.forename: M Elizabeth H
authors.initials: ME
authors.lastname: Hammond
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000906:Antibodies / Q000276:immunology*; D001706:Biopsy; D002648:Child; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D006084:Graft Rejection / Q000453:epidemiology / Q000276:immunology* / Q000473:pathology; D016027:Heart Transplantation; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000276:immunology / Q000473:pathology; D011379:Prognosis; D012189:Retrospective Studies; D012720:Severity of Illness Index; D055815:Young Adult
chemical_list: D000906:Antibodies