Evaluation and management of paravalvular aortic regurgitation after transcatheter aortic valve replacement

Paravalvular aortic regurgitation (PAR) negatively affects the prognosis after transcatheter aortic valve replacement (TAVR) with dramatically increased morbidity and mortality in patients with more than mild PAR. Because transcatheter heart valves are implanted in a sutureless fashion using oversizing to anchor the prosthesis stent frame at the level of the virtual aortic annulus, stent frame underexpansion due to heavily calcified cusps, suboptimal placement of the prosthesis, and/or annulus-prosthesis-size mismatch due to malsizing can contribute to paravalvular leakage. In contrast to open heart surgery, TAVR does not offer the opportunity to measure the aortic annulus under direct vision during the procedure. Therefore, the dilemma before each TAVR procedure is the appropriate sizing of the dimensions of the aortic annulus and to choose not only the size but also the transcatheter heart valve type (self-expanding vs. balloon-expandable) that fits the given anatomy best. Because precise echocardiographic quantification of PAR in patients with TAVR remains challenging especially in the acute implantation situation, a multimodal approach for the evaluation of PAR with the use of hemodynamic measurements and imaging modalities is imperative to precisely quantify the severity of aortic regurgitation immediately after valve implantation and to identify patients who will benefit from corrective measures such as post-dilation or valve-in-valve implantation. Every measure has to be taken to prevent or reduce PAR to provide a satisfying long-term clinical outcome.