Echocardiography in transcatheter aortic valve implantation

Transcatheter aortic valve implantation (TAVI) has become a feasible and effective therapeutic option for patients with severe aortic stenosis and high operative risk or relative contraindications for surgical aortic valve replacement (SAVR). Patient selection plays a crucial role in the success of TAVI. Echocardiography is a mainstay during the whole process starting with the very important morphological evaluation and accurate measurement of the aortic root, followed by guiding the procedure and detecting possible complications, and ending with serial assessment of the patient's heart and the implanted prosthesis. This present article reviews the role of echocardiography before, during, and after transcatheter aortic valve implantation.

Experience with anatomically orientated devices for transapical aortic valve implantation

Transcatheter aortic valve implantation (TAVI) is a new technology, which is rapidly growing to a routine procedure amenable for patients with symptomatic aortic valve stenosis and higher than average risk for conventional aortic valve surgery. The crucial disadvantage of TAVI remains the not well foreseeable risk of more than trivial degree of paravalvular leakage and a high rate of atrioventricular block and consecutive pacemaker implantation. In addition, current implantation techniques do not allow controlling the rotation of first-generation devices that might be beneficial regarding optimal physiological valve performance, optimal coronary flow and avoidance of placement of covered commissures in front of the coronary ostia. These shortcomings had pushed the development of second-generation self-expandable nitinol-based devices for subcoronary implantation that aim a reduction of paravalvular leak and AV-block by anatomical orientated positioning into the aortic root. This review focuses on the description of three different TAVI concepts, which are presently under early clinical evaluation, or have recently received commercial approval, using the transapical approach.