Preventive programs and the development of specific therapeutic measures have helped to significantly reduce the load of cardiovascular risk over the previous decades. This applies to both the epidemiology of cardiovascular disease on the population level and the prognosis of individual patients affected by chronic disease. However, a significant residual hazard, beyond traditional risk models, is persisting. This gap may be filled by recent research that rediscovered thyroid homeostasis as a major determinant of cardiovascular health. Current advances extend to large population-based studies that identified even variation of thyroid function within established population-based reference ranges to be significant risk factors for sudden cardiac death, malignant arrhythmia and other major endpoints. Hence, it is most timely that a “thyro-cardio centric” thematic topic has been selected for this journal in order to bring more insights into the effects of thyroid hormone levels on cardiac health and disease.

Thyroid hormones are among the key mediators affecting cardiovascular function. Although a close link between the thyroid and the heart is known for more than two centuries, it was the recent years that witnessed the emergence of a deeper physiological understanding of the thyro-cardiac axis. This progress was accelerated by the development of new methods in molecular biology, electrophysiology, systems medicine, computational statistics and bioinformatics. The exponential growth of the number of published papers on the thyroid-heart nexus underscores the dynamics of this still evolving interdisciplinary field. It is against this background that the editors have organized the scientific content of this special issue.

Articles in this research topic include basic research papers, results of clinical studies and review articles that give a comprehensive overview on state-of-the-art methodology and recent results from the interface between the biology of thyroid hormones and cardiovascular electrophysiology, paving the way to a better understanding and management of a remaining challenge in predictive, preventive and personalised medicine.