Developing the technique of percutaneous implantation of aortic valves (TAVI) for the treatment of degenerative aortic stenosis: Where are we and what future for TAVI?

The TAVI (Transcatheter Aortic Valve Implantation) is a French innovation, initiated in 2002 by the cardiology team of Rouen University Hospital and whose 20th anniversary is being celebrated this year. This technique consists of implanting a valve prosthesis within the native aortic valve of adults suffering from calcific degenerative aortic stenosis (AS) using standard cardiac catheterization techniques. AS is the most frequent acquired valvular disease of adults, mainly affecting the elderly. Its prevalence increases with age, concerning about 7% of a population older than 75 years, which is considerable. Many patients cannot benefit fromthe only possible treatment, surgical aortic valve replacement (SAVR), a heavy open-heart surgery, due to their advanced age or comorbidities. These patients are doomed to early death, 80% within three years after the onset of the first symptoms. This has motivated our interest for the development of less invasive interventional techniques, such as balloon aortic valve dilatation in 1985, then TAVI in order to overcome the limitations of the first approach. The development of TAVI was a fascinating 20-year odyssey, the main stages of which are summarized in this article. This technique, the mere mention of which raised the worst criticisms, has known a considerable success and a worldwide expansion that defy the imagination. This has resulted from the combination of continuous technological advances since the first case, with rigorous scientific evaluation using a number of controlled registries, but also by several several successive randomized studies comparing TAVI to SAVR in patients at decreasing surgical risk. The non-inferiority or superiority of TAVI on patients improvement and mortality at mid and long-term could be consistently demonstrated and this led to a change in paradigm for the treatment of AS. Currently, TAVI is being validated for any patient, whatever the surgical risk, older than 65 years in the USA or 75 years in Europe, whereas SAVR remains indicated for patients who are not optimal candidates to TAVI. More than 1.5 million patients have been treated with TAVI worldwide and a growth of 4 to 10% per year is predicted. Since 2019, the number of TAVI exceeds that of SAVR in several countries including the USA. Finally, the collateral effects of this breakthrough technology on medical practice and on the development of other valvular and structural interventional techniques is particularly noteworthy. In this regard, the history of TAVI should be very inspiring for the young clinicians and scientists aimed at improving medical therapies.& COPY; 2022 l'Academie nationale de medecine. Published by Elsevier Masson SAS. All rights reserved.