**Abstract**

Paravalvular leaks (PVLs) are complications of a surgical or percutaneous valve replacement. They are persistent defects between the native annulus and the sewing ring, which result in a regurgitant prosthesis. They are observed in 2–18% of patients after a surgical valve replacement (SVR) and in 7–40% after a transcatheter aortic valve replacement (TAVR). Clinical manifestations are heart failure and hemolysis. They develop in 1–5% of PVL patients, and they have a poor prognosis. Surgery was the only available treatment to improve the patient's outcome. But it is a high-risk surgery in frail patients and PVL relapse is not rare. Percutaneous PVL closure has emerged as a promising technique. Nevertheless, it needs a careful assessment, demands high technical expertise, and still has limitations. This chapter focuses on the diagnosis of PVL after a SVR and transcatheter PVL closure (TPVL).

**Keywords:** surgical valve replacement, transcatheter aortic valve replacement, paravalvular leak, transesophageal echocardiography, 3D echocardiography

## **1. Introduction**

Paravalvular leaks (PVLs) are complications of a surgical or percutaneous valve replacement. They are persistent defects between the native annulus and the sewing ring, which result in a regurgitant prosthesis. They are more frequent after a surgical replacement (SVR) of the mitral (SMVR) than the aortic valve (SAVR) (7–17% and 2–10%, respectively) [1–3]. They can be detected early or several decades after the index surgery [4]. PVL reemerged as a frequent and deleterious complication with transcatheter aortic valve replacement (TAVR) development. Where it was reported variably in 7–40% of patients, it decreased with prostheses and technical improvements. Only 1–5% of PVLs result in patent clinical effect [5]; hemolytic anemia or congestive heart failure. In patients with one or both clinical manifestations, spontaneous evolution is unfavorable, and an intervention is indicated. Percutaneous closure seems an optimal therapeutic solution, less invasive than surgery, and has promising results. Nevertheless, this technique demands high technical expertise, and it has its proper limitations and complications, hence indications should be carefully weighed.
