Aortic regurgitation (AR) is an important predictor of adverse prognosis after transcatheter aortic valve implantation (TAVI) by both self-expanding and balloon-expandable prostheses and is predominantly paravalvular (PV). The mounting evidence for moderate/severe PV AR as an independent predictor of mortality is discussed. Moreover, there is an unclear impact on prognosis of mild PV AR that is most likely the result of imperfect assessment of this complication, which currently remains semi-quantitative. The relevance of its accurate quantification to reliable prognostication is described, along with how this data might be used to guide intervention and optimise outcomes of patients with PV AR.