Transcatheter aortic valve implantation: the evidence.

Transcatheter aortic valve implantation (TAVI) is the new standard-of-care for inoperable patients with better outcome than conservative management, including balloon valvuloplasty only. In high-risk patients, TAVI has clearly shown non-inferiority compared with surgical aortic valve replacement. Although data from national multicentre registries are very encouraging and we are already speculating about the use of TAVI in intermediate-risk patients, it is of note that the two commercially available and used transcatheter heart valves (THVs) have not yet been assessed by randomised clinical trials in those patients. Technological advances promise to simplify TAVI and to improve outcome by reducing the rate of TAVI-specific issues such as stroke, peri-prosthetic aortic regurgitation, acute kidney injury, vascular complications and conduction disturbances. Therefore, results from ongoing trials with the available THVs are urgently awaited. In future trials, screening, treatment and follow-up of TAVI patients will need to follow a standardised protocol to achieve better comparability of study data to address, decisively, the question of whether intermediate-risk or low-risk patients may also profit from a less invasive TAVI approach.