title: Does re-operation have an effect on outcome following heart transplantation?
abstract: OBJECTIVE
  Previous cardiac operation has traditionally been considered as a potential risk factor for patients undergoing heart transplantation. This study aimed to evaluate the outcome of patients undergoing heart transplantation as a second cardiac procedure and compare it with primary heart transplantation, using meta-analytical methodology.
  
  
  METHODS
  A literature search was undertaken to identify relevant comparative studies. Outcomes of interest were classified into four categories: (a) intra-operative times; (b) post-operative outcomes; (c) resources; (d) actuarial outcomes.
  
  
  RESULTS
  Seven studies matched the selection criteria, reporting on 1004 patients. Six hundred and twenty-three had transplantation as primary operation and 381 as re-operation. The 1-year, 2-year, and 5-year mortality were similar for the two groups (HR=0.85, p=0.54; HR=0.97, p=0.88; and HR=1.04, p=0.92, respectively). Total operative, cold-ischaemic, by-pass, and cross-clamp times were significantly longer for the re-operation group by 59.44 (p<0.001), 14.62 (p=0.05), 25.24 (p<0.001), and 7.93 (p<0.001)min, respectively. Both ICU and hospital stay were longer for the re-operation group but only the former was statistically significant (WMD=1.37; p=0.02). Post-operative complications were similar, except re-exploration rate and blood transfusion requirement, which were higher in the re-operation group (OR=3.51; p<0.001 and WMD=2.21; p<0.001, respectively).
  
  
  CONCLUSIONS
  Heart transplantation following previous cardiac operation is technically demanding requiring longer operative times compared to primary heart transplantation. It does not, however, add a significant risk to the survival of the patient, and associated morbidity is not significantly compromised.
authors.affiliation: Imperial College London, Department of Bio-Surgery and Technology, St. Mary's Hospital, London, United Kingdom.
authors.forename: Constantinos
authors.initials: C
authors.lastname: Kokkinos
authors.forename: Thanos
authors.initials: T
authors.lastname: Athanasiou
authors.forename: Christopher
authors.initials: C
authors.lastname: Rao
authors.forename: Vasilis
authors.initials: V
authors.lastname: Constantinidis
authors.forename: Christos
authors.initials: C
authors.lastname: Poullis
authors.forename: Andrew
authors.initials: A
authors.lastname: Smith
authors.forename: Michelle
authors.initials: M
authors.lastname: Ridgway
authors.forename: Paris P
authors.initials: PP
authors.lastname: Tekkis
authors.forename: Ara
authors.initials: A
authors.lastname: Darzi
mesh_terms: D006348:Cardiac Surgical Procedures; D016027:Heart Transplantation; D006801:Humans; D007431:Intraoperative Complications; D007902:Length of Stay; D011183:Postoperative Complications; D012086:Reoperation; D016019:Survival Analysis; D016896:Treatment Outcome