Biomarkers of heart transplant rejection: the good, the bad, and the ugly!

Acute cellular rejection (ACR), antibody-mediated rejection (AMR), and cardiac allograft vasculopathy (CAV) are important limitations for the long-term survival of heart transplant recipients. Although much progress has been made in reducing ACR with modern immunosuppressive treatments and continuous biopsy surveillance, there is still a long way to go to better understand and treat AMR, to enable early detection of patients at risk of CAV, and to reduce the development and sustained progression of this irreversible disease that permanently compromises graft function. This review considers the advances made in ACR detection and treatment allowing a more prolonged survival and the risk factors leading to endothelial injury, dysfunction, inflammation, and subsequent CAV, as well as new treatment modalities for CAV. The review also evaluates the controversies around the definition, pathogenesis, and treatment of AMR. To date, much progress is still needed to significantly reduce post-transplant complications and increase graft and patient survival.