Prevalence and risks of allosensitization in HeartMate left ventricular assist device recipients: the impact of leukofiltered cellular blood product transfusions.
OBJECTIVE
Allosensitization of left ventricular assist device recipients has been associated with perioperative transfusion of cellular blood products. The relative sensitizing contribution of leukofiltered cellular blood products, however, remains unclear. We investigated the pattern of sensitization in left ventricular assist device recipients in relation to cellular blood product transfusions received.


METHODS
Seventy-one consecutive nonsensitized recipients of the HeartMate left ventricular assist device (Thoratec Corporation, Pleasanton, Calif) as a bridge to transplantation were reviewed. Panel-reactive HLA antibody levels at consecutive times after device implantation were correlated with perioperative cellular blood product transfusions.


RESULTS
Fifty-four patients received leukofiltered cellular blood products (transfused), whereas 17 patients received only fresh-frozen plasma (nontransfused). Among nontransfused patients, 58.8% (10/17) became sensitized during mechanical support, versus 35.2% of transfused patients (19/54, P = .15). There was a trend toward more sensitization during the 12 weeks after device placement in nontransfused patients. Kaplan-Meier analysis revealed significantly more sensitization in nontransfused patients than in transfused patients, despite equal rates of transplantation (P = .05). A dose-response analysis revealed significant trends toward less sensitization and lower peak panel-reactive antibody level with more cellular blood product transfusions (P = .04). Multivariate Cox regression revealed only increasing transfusions to be associated with a reduced risk of sensitization (hazard ratio 0.18, P = .01).


CONCLUSIONS
Sensitization becomes more prevalent with increasing length of support. Avoidance of perioperative leukocyte-filtered cellular blood product transfusions does not decrease the incidence or degree of HLA sensitization. Conversely, cellular blood product transfusions may be associated with lessened alloimmunization and may mitigate the sensitization seen in recipients of the HeartMate left ventricular assist device as a bridge to transplantation.
Drakos
Stavros G
SG
Utah Transplantation Affiliated Hospitals (UTAH) Cardiac Transplant Program, Salt Lake City, Utah, USA.
Stringham
James C
JC
Long
James W
JW
Gilbert
Edward M
EM
Fuller
Thomas C
TC
Campbell
Beverly K
BK
Horne
Benjamin D
BD
Hagan
Mary E
ME
Nelson
Karl E
KE
Lindblom
Judy M
JM
Meldrum
Patty A
PA
Carlson
Joanne F
JF
Moore
Stephanie A
SA
Kfoury
Abdallah G
AG
Renlund
Dale G
DG
D001803:Blood Transfusion; D016009:Chi-Square Distribution; D005260:Female; D006680:HLA Antigens / Q000276:immunology*; D006353:Heart-Assist Devices; D006801:Humans; D007518:Isoantibodies / Q000097:blood*; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D016016:Proportional Hazards Models; D018709:Statistics, Nonparametric
D006680:HLA Antigens; D007518:Isoantibodies