Transcatheter aortic valve implantation (TAVI): current indications and future scenarios

Th e introduction of transcatheter aortic valve implantation (TAVI) has represented a major breakthrough in the management of patients with symptomatic severe aortic valve stenosis. Th is approach is superior to conservative treatment in patients deemed inoperable with traditional surgical aortic valve replacement (AVR)1 and non-inferior or even superior to AVR in patients at high or intermediate operative risk according to the Society of Th oracic Surgeons (STS) score.2-4 Indications to TAVI are thus currently expanding, and some ongoing studies are investigating the role of TAVI in low-risk symptomatic patients or even asymptomatic patients with severe aortic valve stenosis.5 Th e exponential growth of TAVI has been related to some key advancements in diagnostic and procedural aspects: implementation of dedicated software for multi-detector computed tomography for valve sizing and characterization of the access site, iteration of devices with signifi cant reduction of paravalvular leak and the need for pacemaker implantation, and the use of smaller-caliber delivery systems, with reduced rates of vascular com plications. Randomized trials comparing TAVI vs. AVR for the treatment of severe aortic valve stenosis have been based on the STS score, but increasing experience and accruing evidence suggest a more complex algorithm for clinical decision making on the optimal treatment for patients with severe aortic valve stenosis, wherein surgical scores should be integrated with other anatomic and physiologic factors.