Transcatheter Aortic Valve Implantation for Pure Aortic Regurgitation

Abstract

The incidence of noncalcific pure aortic regurgitation (AR) is much lower than that of calcific aortic stenosis (AS). Conventional aortic valve surgery is the gold standard for the treatment of pure AR. However, a number of patients with AR have been declined for open-heart surgery because of age and other significant comorbidities. Although transcatheter aortic valve implantation (TAVI) is now a standard treatment for calcific AS in high risk patients, TAVI remains an investigational therapy for pure AR. This is because the majority of transcatheter heart valves (THV) require calcification of the aortic valve for their anchoring. A lack of calcification can result in a high incidence of valve migration and paravalvular leak. The Edwards SAPIEM valve is generally avoided in patients with pure AR. However, this valve with a dock device was successfully used in the treatment of pure AR in a small number of patients. The Medtronic CoreValve has been used with some success in patients with pure AR, but this is associated with high incidences of valve migration and paravalvular leaks. Some THVs, such as Direct Flow THV and Acurate THV, incorporate self-seating geometry that facilitates optimal positioning at the aortic annulus. A few case reports have showed the feasibility of these valves in the treatment of pure AR. Other valves, such as Engager, JenaValve and J-Valve THVs, have further incorporated design elements, such as 3 “arches”, 3 “feelers”, and 3 “graspers”, respectively, which facilitate both self-positioning and anchoring at the aortic valve. Clinical experience has suggested that these valves are probably more suitable for the treatment of pure AR. Excellent outcomes with minimal paravalvular leaks and 30-day mortality rate have been reported following TAVI with the use of J-Valve in patients with pure AR.