Paravalvular regurgitation: The unconquered frontier in TAVR

摘要

Transcatheter aortic valve replacement (TAVR) has been a major development in the field of interventional cardiology and has become the treatment of choice for inoperable patients with severe symptomatic aortic stenosis. It is also an alternative therapeutic option to surgical aortic valve replacement (SAVR) in patients at high operative risk. The initial enthusiasm of TAVR technology is somewhat marred by a higher rate of paravalvular regurgitation (PVR) as compared to SAVR, which adversely impacts mortality. The problem of PVR is present with both types of most commonly used transcatheter heart valve systems (balloon-expandable, Edwards Lifesciences, Irvine, CA, USA; self-expandable CoreValve, Medtronic, Minneapolis, MN, USA). After SAVR moderate-to-severe aortic regurgitation is infrequent, occurring in approximately 4% of patients, and adversely affects mortality as well. The incidence of moderate-to-severe PVR in patients with TAVR is much higher-CoreValve (9-21%) and Edwards (6-13.9%).In SAVR, the calcified leaflets are excised and the prosthetic valve is sized and seated under direct vision with sealing of any apparent areas of leakage. TAVR, on the other hand, is remotely deployed via a delivery catheter under fluoroscopic and echo guidance with less direct control. The native calcined leaflets are left in place with the potential of creating an irregular apposition surface with suboptimal seal leading to PVR.