title: Improved outcomes with an implantable left ventricular assist system: a multicenter study.
abstract: BACKGROUND
  Cumulative experience with the Novacor wearable electric left ventricular assist system (LVAS) now exceeds 850 recipients. The pump inflow conduit (IFC) has been implicated in embolic complications.
  
  
  METHODS
  Clinical outcomes were compared for two IFC designs in a retrospective, nonrandomized, multicenter study. The original IFC (woven, unsupported, crimped polyester: control group) and an alternative IFC (knitted, gelatin-sealed, integrally supported, uncrimped polyester: test group) were utilized upon availability in North American and European centers. Differences in cerebral embolism to 180 days postimplant were analyzed.
  
  
  RESULTS
  Four hundred ninety patients implanted between August 1996 and August 1999, were studied. Two hundred eighty-eight received the control IFC and 202 received the test IFC. The groups (control, test) were well matched for age (48, 49 years), etiology (idiopathic 53%[152 of 288], 55% [112 of 202]; ischemic 34% [97 of 288], 33% [66 of 202]) and mean observation time (97, 91 days). The incidence of embolic cerebrovascular accidents (CVA) was 21% (60 of 288) in the control and 12% (24 of 202) in the test group (p = 0.010). Independent risk factors for embolic CVA were found to be preimplant acute myocardial infarction (odds ratio 4.3), age above 50 years (odds ratio 2.1), and ischemic etiology (odds ratio 1.7). There was no difference in survival between the groups (71% [205 of 288], 68% [137 of 202]).
  
  
  CONCLUSIONS
  The alternative (test) IFC has significantly reduced the incidence of embolic CVA. This improvement is likely due to increased resistance to deformation at implant, improved neointimal adhesion, and more favorable blood flow characteristics within the conduit.
authors.affiliation: Department of Cardiothoracic Surgery, Falk Research Center, Stanford University School of Medicine, California 94305-5407, USA.
authors.forename: P M
authors.initials: PM
authors.lastname: Portner
authors.forename: P G
authors.initials: PG
authors.lastname: Jansen
authors.forename: P E
authors.initials: PE
authors.lastname: Oyer
authors.forename: D R
authors.initials: DR
authors.lastname: Wheeldon
authors.forename: N
authors.initials: N
authors.lastname: Ramasamy
mesh_terms: D009202:Cardiomyopathies / Q000601:surgery*; D005260:Female; D006353:Heart-Assist Devices; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D017202:Myocardial Ischemia / Q000601:surgery*; D012189:Retrospective Studies; D016896:Treatment Outcome