Clin Res Cardiol (2022). https://doi.org/10.1007/s00392-022-02002-5

Predictors Of Humoral Response To COVID-19 Vaccination In Heart Transplant Recipients

S. T. Küppers1, F. Memenga1, K. Borof1, D. Knappe2, S. Blankenberg3, M. Barten4, H. Reichenspurner4, P. Kirchhof1, C. Magnussen1, M. Rybczynski2

1Klinik für Kardiologie, Universitäres Herz- und Gefäßzentrum Hamburg GmbH, Hamburg; 2Allgemeine und Interventionelle Kardiologie, Universitäres Herz- und Gefäßzentrum Hamburg GmbH, Hamburg; 3Klinik für Kardiologie, Universitäres Herz- und Gefäßzentrum UKE Hamburg GmbH, Hamburg; 4Klinik und Poliklinik für Herz- und Gefäßchirurgie, Universitäres Herz- und Gefäßzentrum Hamburg GmbH, Hamburg;

Purpose A reduced formation of IgG antibodies after COVID-19 vaccination has been reported in immunosuppressed heart transplant (HT) recipients, while predictors of the decreased humoral response in these patients remain elusive.   Methods In 68 HT recipients who previously received two doses of a COVID-19 vaccine, anti-SARS-CoV-2 spike IgG (anti-spike IgG) were quantified (LIAISON® SARS-CoV-2 TrimericS IgG assay) during routine visits. IgG concentrations at or above 33.8 BAU/ml were considered positive, as defined by the manufacturer. Clinical characteristics including the immunosuppressive regimen were assessed. We performed regression analyses to identify predictors of humoral response.   Results Of 68 HT recipients (44 (65%) male, median age 54 years (IQR 41-64), median time since HT 7.4 years (1.7-13.0)), 56 patients (82%) were treated with calcineurin-inhibitors, 35 (51%) with mycophenolate mofetil, 47 (69%) with everolimus, and 33 (49%) with prednisolone. 60 patients (88%) received two doses of an mRNA vaccine (50 patients BNT162b2, 10 mRNA-1273) and 8 patients (12%) two doses of the vector vaccine AZD1222. Two patients (2.9%) reported a prior COVID-19 infection. The median interval between the two vaccine shots was 41.5 days (35.0, 42.0). A positive humoral response 40 days after the second dose was detected in 26 patients (38%). Comparing the two types of vaccines used, antibody positivity rates were not significantly different (p = 0.10). Upon multivariate analysis, older patient age (p=0.006), shorter time since HT (p=0.022), male sex in combination with time since HT (p=0.023 for interaction effect), and use of prednisolone (p<0.001 in a tobit linear regression) were associated with lower log-transformed COVID-19 antibody titers. There was no detectable effect of vaccine type or of other immunosuppressive agents.   Conclusion Older age, shorter time since transplantation, and treatment with prednisolone appear to be associated with lower anti-spike IgG concentrations after COVID-19 vaccination in HT patients. Overall humoral response rates were low (38%), regardless of the type of vaccine used or type of non-prednisolone immunosuppressive agent. Further studies are needed to determine the clinical effectiveness of COVID-19 vaccination in HT recipients and the need for specific booster vaccinations in this vulnerable population.

https://dgk.org/kongress_programme/jt2022/aP1195.html