Guest Editor: Prof Nicolas Van Mieghem, Thoraxcenter, Erasmus MC, Rotterdam, the Netherlands 

Aortic regurgitation is the third most common valvular disease, but remains a conundrum in terms of pathology, frequency, diagnosis and treatment. A significant proportion of patients with severe aortic regurgitation are left untreated and face impaired functional status and prognosis. The root cause for this reality is diverse and includes advanced age, frailty and comorbidities that often coincide with severe aortic regurgitation, inconclusive diagnostic imaging studies that result in underreporting and missed diagnosis, concomitant aortic pathology with incremental operative risk, and treatment expertise that may be limited to open heart surgery in many institutions and geographies. 

The aim of this collection is to provide a holistic overview on key facets of aortic regurgitation with specific attention to innovative therapeutic strategies. Aortic valve repair and dedicated transcatheter technologies have emerged and may alter the approach of patients with aortic regurgitation by providing treatment options that ultimately may improve quality of life and life expectancy.