title: Routine thymectomy in congenital cardiac surgery changes adaptive immunity without clinical relevance.
abstract: The actual importance of the thymus in both children and adults is largely unclear. In congenital cardiac surgery, a partial or total thymectomy is frequently performed to improve access to the heart and great vessels. We performed a literature search to evaluate the effect on the adaptive immune system of the removal of thymus tissue in patients with congenital heart disease. A PubMed search according to Dunning's standard provided 149 articles, of which 13 addressed our search question. Each study has been tabulated with author, cases, controls, follow-up, methods, results and limitations. A first group of articles repeatedly showed the effect on the T-cell compartment, including the impact on subgroups of this compartment. More recent studies, usually with a longer follow-up, confirm that the earlier changes in T-cell population appear to be permanent. Only one author found a normalization of T-cell population five years after thymectomy. In contrast to these clear changes in T-cell population, there is currently no clear clinical relevance. A literature search on thymectomy in congenital cardiac surgery revealed clear changes in T-cell-related immunity; however, there is a lack of clinical relevance. Further investigation of the adaptive immune system is required to explain this discrepancy.
authors.affiliation: Department of Cardiovascular Sciences, Research Unit of Experimental Cardiac Surgery, KU Leuven, Leuven, Belgium jorg.roosen@gmail.com.
authors.forename: Jorg
authors.initials: J
authors.lastname: Roosen
authors.affiliation: Department of Cardiovascular Sciences, Research Unit of Experimental Cardiac Surgery, KU Leuven, Leuven, Belgium.
authors.forename: Wouter
authors.initials: W
authors.lastname: Oosterlinck
authors.affiliation: Department of Cardiovascular Sciences, Research Unit of Experimental Cardiac Surgery, KU Leuven, Leuven, Belgium.
authors.forename: Bart
authors.initials: B
authors.lastname: Meyns
mesh_terms: D056704:Adaptive Immunity; D006330:Heart Defects, Congenital / Q000175:diagnosis / Q000276:immunology / Q000601:surgery*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D012307:Risk Factors; D013934:Thymectomy / Q000009:adverse effects; D016896:Treatment Outcome
keywords: Cardiac surgery; Congenital heart disease; Immune function; Thymectomy