TAVI in LOW RISK in the REAL WORLD

Severe aortic stenosis is the most common valvular heart disease worldwide. Its prevalence increases with age and is estimated to affect approximately 2% of the population aged 70-80 and as many as 9% of adults over 80 years of age.¹ Given the progressive aging of the population and the ever-increasing life expectancy, its prevalence will continue to rise, representing not only a topic of scientific interest but also a significant public health issue. In the past, the treatment of severe aortic stenosis was strictly the domain of cardiac surgery, and the gold standard was aortic valve replacement via open-heart surgery. In 2002, however, in an effort to offer a compassionate treatment option to patients considered high-risk or even ineligible for traditional surgery, transcatheter aortic valve replacement (TAVI) was introduced. The PARTNER study was the first randomized trial to evaluate the use of a balloon-expandable valve (Sapien - Edwards). The study consisted of two cohorts: Cohort A, comprising patients at high surgical risk, demonstrated that TAVI was non-inferior to SAVR in terms of 1-year all-cause mortality.

And a second cohort, Cohort B, which enrolled patients who were not considered suitable candidates for surgical aortic valve replacement (SAVR) and demonstrated a reduction in the rate of all-cause mortality or rehospitalization with transcatheter aortic valve implantation (TAVI) compared with standard medical therapy.² The efficacy and safety of transcatheter aortic valve replacement were quickly recognized by the ESC/EACTS and ACC/AHA, which incorporated this technique into their guidelines in 2012 and 2014, respectively. TAVI was in fact recommended as a Class I recommendation for patients ineligible for cardiac surgery and as a Class IIA recommendation for high-risk patients. At the same time, the CoreValve Extreme Risk Pivotal and CoreValve US Pivotal studies demonstrated the safety and efficacy of a self-expanding valve in the treatment of aortic stenosis (CoreValve - Medtronic); and in the second study, even its superiority over traditional surgery.

Since then, several studies have been conducted to demonstrate the safety and efficacy (non-inferiority) of TAVI compared to SAVR, even in intermediate-risk patients, including PARTNER 2 (which used a second-generation Sapien XT valve) and SURTAVI (CoreValve and Evolut R). Once again, guidelines were not long in coming, and in 2017, the ESC/EACTS classified the use of TAVI in patients with increased risk (intermediate or high) as Class I. Two further studies, PARTNER 3 and Evolut Low Risk, subsequently demonstrated the non-inferiority of TAVI compared to SAVR, thereby securing approval in Europe and the United States for use in low-risk patients. These valves have distinguished themselves by achieving excellent results across various outcomes in low-risk patients. In fact, Sapien 3 demonstrated superior results in terms of 1-year mortality and stroke rates and a lower need for pacemaker implantation compared to Evolut, which, however, achieved better hemodynamic performance within its own studies. Currently, registries showing TAVI outcomes in real-world patients are few and limited; therefore, it is important to assess whether data on outcomes in low-risk all-comers outside of trial settings align with trial results.

Patients included in the retrospective part of the study will be enrolled from January 2021 through September 2024 and will account for approximately two-thirds of the patients enrolled in the CCM.

Patients included in the prospective part of the study will be enrolled from October 2024 through August 2025.