PurposeThe heart receives cervical and thoracic sympathetic contributions. Although the stellate ganglion is considered the main contributor to cardiac sympathetic innervation, the superior... Show morePurposeThe heart receives cervical and thoracic sympathetic contributions. Although the stellate ganglion is considered the main contributor to cardiac sympathetic innervation, the superior cervical ganglia (SCG) is used in many experimental studies. The clinical relevance of the SCG to cardiac innervation is controversial. We investigated current morphological and functional evidence as well as controversies on the contribution of the SCG to cardiac innervation.MethodsA systematic literature review was conducted in PubMed, Embase, Web of Science, and COCHRANE Library. Included studies received a full/text review and quality appraisal.ResultsSeventy-six eligible studies performed between 1976 and 2023 were identified. In all species studied, morphological evidence of direct or indirect SCG contribution to cardiac innervation was found, but its contribution was limited. Morphologically, SCG sidedness may be relevant. There is indirect functional evidence that the SCG contributes to cardiac innervation as shown by its involvement in sympathetic overdrive reactions in cardiac disease states. A direct functional contribution was not found. Functional data on SCG sidedness was largely unavailable. Information about sex differences and pre- and postnatal differences was lacking.ConclusionCurrent literature mainly supports an indirect involvement of the SCG in cardiac innervation, via other structures and plexuses or via sympathetic overdrive in response to cardiac diseases. Morphological evidence of a direct involvement was found, but its contribution seems limited. The relevance of SCG sidedness, sex, and developmental stage in health and disease remains unclear and warrants further exploration.Graphical abstractAn overview of the current literature derived from morphological and functional data on the involvement of SCG in cardiac innervation, relevance of sidedness, sex differences, and pre- and postnatal differences in various species. X = Information not available Show less
The heart is innervated by the autonomic nervous system, which can be divided into sympathetic and parasympathetic parts. The balance between cardiac sympathetic and parasympathetic innervation is... Show moreThe heart is innervated by the autonomic nervous system, which can be divided into sympathetic and parasympathetic parts. The balance between cardiac sympathetic and parasympathetic innervation is critical for maintaining normal cardiac function. After myocardial infarction, sympathetic hyperinnervation has been discovered in patients as well as in animal models, which has raised growing awareness in relation to arrhythmogenesis. However the mechanism is not clear yet. In this thesis, we hypothesize a role for epicardium-derived cells (EPDCs) in this process. In addition, we aimed to study ganglia remodeling after myocardial infarction. We explored: i) the role of EPDCs in promoting cardiac sympathetic re-/hyperinnervation after cardiac damage in vitro, ii) the impact of sex of EPDCs on cardiac innervation, iii) the generation of inducible proliferative human EPDCs (iEPDCs), iv) neuronal remodeling of superior cervical ganglia after myocardial infarction and v) the molecular signature of SCG revealed by single nucleus RNA sequencing. Show less
