title: Noninvasive monitoring of acute and chronic rejection in heart transplantation.
abstract: OBJECTIVE
  Recent years have seen advances in the early detection of cardiac graft rejection.
  
  
  RESULTS
  We review the possibilities offered by tissue Doppler imaging and speckle tracking echocardiography, cardiac magnetic resonance, cardiac computed tomography, single positron emission tomography, gene expression profiling, and quantitation of donor-derived cell-free DNA, and microRNAs.
  
  
  CONCLUSIONS
  Noninvasive monitoring of acute and chronic rejection after cardiac transplantation is an unmet need and remains a challenge. Imaging techniques and peripheral blood biomarkers are the most commonly used approaches, and in recent years there has been great progress. Gene expression profiling seems to be useful for ruling out the presence of a moderate to severe acute cellular rejection in stable, low-risk patients. Newer monitoring tools, like donor-derived cell-free DNA or microRNA, seem to be promising for individualizing immunosuppressive therapies and better understanding the mechanisms of rejection.
authors.affiliation: Unidad de Insuficiencia Cardiaca Avanzada y Trasplante Cardiaco, e Instituto Biomédico de A Coruña, Complejo Hospitalario Universitario de A Coruña-Centro de Investigacion Biomedica en Red en Enfermedades Cardiovasculares CIBERCV, Universidade da Coruña, A Coruña, Spain.
authors.forename: Maria G
authors.initials: MG
authors.lastname: Crespo-Leiro
authors.forename: Gonzalo
authors.initials: G
authors.lastname: Barge-Caballero
authors.forename: David
authors.initials: D
authors.lastname: Couto-Mallon