Although atrial fibrillation (AF) development has been demonstrated to be associated with underlying cardiovascular conditions such as hypertension, valvular heart disease or diabetes mellitus; in a subset of relatively younger patients, no cardiopulmonary disease diagnosis can be established. Younger AF patients without clinical or echocardiographic evidence of cardiopulmonary disease are defined as lone AF patients. Despite the decrease in lone AF prevalence due to advances in understanding of AF pathogenesis, there are still issues yet to be resolved. Future studies are needed to demonstrate the cost- effectiveness of the routine use of more advanced diagnostic tools, such as non- invasive assessment of endothelial function, autoimmune markers or genetic screening and whether they would have clinical implications on treatment of lone AF.

This review focuses on the suggested mechanisms in lone AF initiation and maintenance.