Global disparities in access to cardiac care for congenital heart disease in low- and middle-income countries: A bibliometric analysis

Objective: The aim of the study was to conduct a comprehensive bibliometric analysis of publications on inequalities in access to cardiac surgical care for congenital heart defects in order to systematize knowledge, identify the main research areas and determine promising areas for further study.Methods: A systematic bibliographic search was performed in the international Scopus and Web of Science databases for the time period from 2010 to 2025 using the keyword search strategy.To analyze the bibliometric data, we used the specialized software tool VOS viewer, which made it possible to create visualizations of network connections of keywords, conduct a cluster analysis of thematic areas, construct time maps of the field evolution (overlay visualization) and assess the density of research areas (density visualization).Results: The structure of the research field is represented by five interconnected thematic clusters: perinatalepidemiological direction and organization of healthcare systems; clinical and diagnostic aspects and cardiac surgery; socio-economic determinants and insurance systems; clinical outcomes and resource provision, health policy and inequalities in access to care.The central connecting element is the term "congenital heart defects", integrating all thematic domains.Key mediator functions are performed by the nodes of prenatal diagnosis, echocardiography, insurance, health disparities.Time analysis showed a shift in research focus from clinical and technical problems to social aspects of inequalities.Density analysis revealed a concentration of publications around pediatric aspects with an insufficient representation of studies of adult patients, telemedicine technologies and quality of life.Conclusion: Modern scientific literature demonstrates fragmentation of studies, a pronounced pediatric orientation, geographical heterogeneity (dominance of publications from developed countries) and the prevalence of retrospective methodological approaches.