Heart failure can be the final stage of almost any type of cardiovascular diseases. Such diseases are the leading cause of recurrent hospital stay and mortality in developed countries, and an increasingly important cause of morbidity and mortality in developing countries. In consideration of the growing incidence of this syndrome, the Province of Trento (Northern Italy) supports a research project called e-Heart Failure. The aims of this project include the implementation of a web-based patient record management system which must allow all the professionals involved in the care process to provide a shared and continuous care. This paper emphasizes the role of ontologies in supporting the continuity of care. In a complex scenario where multiple agents co-operate in order to allow continuity of care, ontologies are the essential glue to ensure semantic consistency to data and knowledge shared by the different actors involved in the process, including patients and their families.