Page 15 - Heart Transplant Guidelines
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Heart Function Service: Heart Transplant Guidelines

               to transplant across the antibodies and deal with the rejections etc afterwards. The last two options are
               discussed further below.

               The presence and strength of the HLA antibody is detected by the HLA single antigen test and reported
               as mean fluorescence intensity (MFI).  If the amount of antibody “saturates” the HLA columns then
               repeateing the test with serial dilutions enables the antibody titer to be determined. When an HLA
               antibody measures above 7000 MFI, it is correlated with a positive crossmatch by flow cytometry or the
               complement dependent cytotoxicity (CDC) test. At Children’s Medical Center, Dallas, an HLA antibody
               measurement of >3000 MFI is correlated with a positive crossmatch. Patients that are sensitized pre
               transplant have a reduced likelihood of a “matched organ”. The actual likelihood depends upon the
               number of different antibodies formed (often called the panel reactive antibody or PRA). To increase the
               chances of a “matched” transplant (and thus less rejection) desensitization can be undertaken to reduce
               the antibody strength and breadth. Desensitization can thus be undertaken prior to transplant if the
               patients is highly sensitized to potential donors. Scientific validation of these strategies has yet to be
               achieved.  If desensitization is contemplated then the plan should be discussed with the heart transplant
               team including the immunologist and parents should be informed about the risks and outcomes based
               on current literature and the discussion documented in the medical record.

               Guideline for Patients with a Positive Retrospective Cross-Match
               The following guideline is based on the CTOTC-04 study. This guideline will be used for all sensitized
               patients with significant DSAs identified by virtual cross match at the time of heart transplantation.

               Pre-Transplant Guideline:

               Patient who have HLA antibodies identified at time of evaluation require a virtual cross-match when a
               donor becomes available. Coordinator will call HLA Lab at the time of donor offer.

               Peri-Transplant Guideline:

                   •  Standard intraoperative steroids pre cross clamp release
                   •  Peri-operative antibody removal will be performed via plasmapheresis at start of
                       cardiopulmonary bypass (CPB) and/or within 4 hours of CPB initiation.
                   •  A minimum of one and maximum of three volume plasmapheresis will be performed depending
                       on MFI of DSAs (<4000MFI = 1 vol, 4000-8000MFI = 2 vol, >8000MFI = 3 vol)

               Post-Transplant Guideline:


               Thymoglobulin Induction per guideline to be given after plasmapheresis

               The following additional steps will be followed if retrospective cross match returns positive.


                   •  Post-operative plasmapheresis will be performed within 24 hours of patient arrival to the ICU
                       following transplant.
                   •  Plasmapheresis will be performed per our institution guideline – coordinator to alert Blood Bank

               Updated December 14, 2018                                                                   15
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