Outcomes of C4d+ Immunostaining in Heart Transplantation: Is All Immunologic AMR Bad?
Cedars Sinai Medical Center, Los Angeles, CA.
Meeting: 2018 American Transplant Congress
Abstract number: 169
Keywords: Antibodies, Biopsy, Rejection
Session Information
Session Name: Concurrent Session: The Guest That NEVER Leaves: Immunologic Challenges in Heart Transplantation
Session Type: Concurrent Session
Date: Sunday, June 3, 2018
Session Time: 4:30pm-6:00pm
Presentation Time: 5:06pm-5:18pm
Location: Room 4C-3
Purpose: Antibody-mediated rejection (AMR) remains a threat to patients (pts) following heart transplant (HTx). C4d immunostaining is one component involved in the diagnosis of AMR and capillary deposition of C4d in endomyocardial biopsies (EMB) has been associated with poor outcome. However, the outcomes in asymptomatic HTx pts with a C4d+ EMB remains unclear. Therefore, we sought to evaluate the impact of C4d+ immunostaining on outcomes in asymptomatic heart transplant recipients.
Methods: Between 2010 and 2015, we reviewed 6,252 biopsies of 583 heart transplant recipients. We selected 499 patients: 415 pts with no C4d on EMB vs. 84 pts with C4d+ on EMB. A C4d+ EMB (AMR1i) was defined as “diffuse capillary staining” by immunoperoxidase and/or “3+/4+ vascular” staining by immunofluorescence. Pts with any weak staining as well as AMR2/3 pts were excluded. Subsequent 1 and 2 year outcomes assessed included: Survival, freedom from cardiac allograft vasculopathy (CAV: defined as any angiographic stenosis ≥ 30%), freedom from non-fatal major adverse cardiac events (NF-MACE: myocardial infarction, new congestive heart failure, percutaneous coronary intervention, ICD/pacemaker implant, and stroke), and freedom from any-treated rejection.
Results: The mean time to C4d+ EMB was 36 days. Pts who developed C4d on EMB had significantly less 1-year subsequent freedom from AMR2 compared to the no C4d group (89.9% vs 98.7%, p < 0.0001). However, there was no significant difference between the two groups for subsequent 1-year survival, freedom from CAV, freedom from NF-MACE, and freedom from any-treated rejection.
Conclusion: Despite more AMR 2, patients with lone AMR1i in the first year of transplant appear to have acceptable outcomes compared to pts with no C4d deposition. Further study in a larger cohort of pts is needed to confirm these findings.
| Endpoints | C4d+ on EMB (n=84) | No C4d+ on EMB (n=415) | P-Value |
| Subsequent 1-Year Survival | 93.5% | 91.9% | 0.650 |
| Subsequent 1-Year Freedom from CAV | 94.5% | 91.6% | 0.341 |
| Subsequent 1-Year Freedom from ATR | 82.8% | 85.4% | 0.473 |
| Subsequent 1-Year Freedom from ACR | 92.0% | 93.2% | 0.757 |
| Subsequent 1-Year Freedom from AMR | 89.9% | 98.7% | <0.001 |
| Subsequent 1-Year Freedom from NF-MACE | 91.9% | 94.5% | 0.438 |
CITATION INFORMATION: Rafiei M., Patel J., Kransdorf E., Levine R., Dimbil S., Mersola S., Esmailian G., Geft D., Chang D., Czer L., Kobashigawa J. Outcomes of C4d+ Immunostaining in Heart Transplantation: Is All Immunologic AMR Bad? Am J Transplant. 2017;17 (suppl 3).
To cite this abstract in AMA style:
Rafiei M, Patel J, Kransdorf E, Levine R, Dimbil S, Mersola S, Esmailian G, Geft D, Chang D, Czer L, Kobashigawa J. Outcomes of C4d+ Immunostaining in Heart Transplantation: Is All Immunologic AMR Bad? [abstract]. https://atcmeetingabstracts.com/abstract/outcomes-of-c4d-immunostaining-in-heart-transplantation-is-all-immunologic-amr-bad/. Accessed May 16, 2025.« Back to 2018 American Transplant Congress