**Abstract**

Degenerative aortic valve disease is the most common heart valve disease in western countries. After the onset of symptoms, the prognosis of aortic stenosis is poor, despite optimal medical therapy. In recent years transcatheter aortic valve implantation has been affirmed as a viable treatment for patients with high to low surgical risk. Patient screening and procedural planning are crucial for minimizing complications and achieving procedural success. In the last decade, we have seen a progressive technological development in the percutaneous approach, allowing for expanding indications even in low-risk populations. Here we report a brief review summarizing patient screening and procedural planning in patients with aortic valve disease undergoing a transcatheter approach.

**Keywords:** aortic valve stenosis, aortic valve disease, transcatheter aortic valve implantation, transcatheter aortic valve replacement, interventional cardiology

## **1. Introduction**

Alongside the progressive aging of the general population, aortic valve disease is currently one of the most common heart valve diseases worldwide, and its management is going to have a central role in public health, with an expected doubling of the cases in the next 50 years [1, 2]. This topic is particularly significant in developed countries, as in the United States, 4.2 to 5.6 million (approximately 2.5% of the population) are estimated to have a clinically relevant form of heart valve disease in which aortic valve diseases account for 35% of cases [3]. Notwithstanding worldwide primary etiology of aortic stenosis is rheumatic fever. In western countries, regular access to antibiotic therapy and the aging of the population made calcific aortic valve disease, its most common cause, giving account to the rise of aortic stenosis as the most significant heart valve disease in the elderly population [4].

Transcatheter aortic valve implantation (TAVI) has progressively emerged as a valid alternative and choice since 16 April 2002, the date of the world's first TAVI, performed by Alain Cribier in Lyon (France). In the European Society of Cardiology (ESC) 2012 Guidelines TAVI was limited to surgical high/prohibitive risk patients [5], mainly

based on the results of the Placement of Aortic Transcatheter Valves I (PARTNER I; NCT005308944) trial. This trial investigated patients with severe aortic stenosis who were not suitable candidates for surgery; TAVI, as compared with standard therapy, significantly reduced the rates of death from any cause (71.8% vs. 93.6%, Hazard Ratio 0.50; 95% CI 0.39–0·65; p < 0.0001), cardiovascular death (57.3% vs. 85.9%; p < 0.0001), repeat hospitalizations (47.6% vs. 87.3%; p < 0.0001), and cardiac symptoms in terms of New York Heart Association (NYHA) class improvement (NYHA III-IV 14.3% vs. 40%; p = 0.531) [6]. In 2016 PARTNER II trial (NCT01314313), comparing SAVR and TAVI in a randomized trial considering intermediate-risk, patients concluded that TAVI had a similar rate of the primary endpoint (death and disabling stroke) at 2 years follow-up in the overall cohort (Hazard Ratio 0.87; 95% CI 0.71–1.07; p = 0.18) and lower in the transfemoral-access cohort (Hazard Ratio 0.78; 95% CI 0.61–0.99; p = 0.04). On the other hand, surgery demonstrated fewer major vascular complications and less paravalvular aortic regurgitation compared to transcatheter approach [7]. In 2019 results from PARTNER III trial (NCT02675114), comparing SAVR and TAVI in surgical low-risk, patients confirmed that the rate of the composite of death, stroke, or rehospitalization at 1 year was significantly lower with TAVI than with conventional surgery (8.5% vs. 15.1%) [8]. In parallel to PARTNER trials, based on a balloon-expandable prosthesis (Edwards Sapien valve), surgical replacement and transcatheter aortic valve implantation (SURTAVI - intermediate-risk; NCT01586910) and Evolut (low-risk; NCT02701283) trials were conducted, comparing standard surgical therapy to transcatheter implantation of a self-expandable aortic prosthesis (Medtronic Evolut valve). In both studies, TAVI was not inferior to surgery in reducing the primary endpoint of death from any cause or disabling stroke at 24 months [9, 10]. In 2019, based on the evidence generated by these clinical trials, the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA) approved TAVI for the treatment of symptomatic severe aortic stenosis in surgical low-risk patients (**Figure 1**) [11, 12].

2021 ESC/EACTS Guidelines (**Figure 2**) for the management of valvular heart disease have a more balanced approach, currently recommending TAVI for elderly (≥ 75 anni, STS-PROM/EuroSCORE II >8%) or patients unsuitable for surgery and

*Overview of the most important clinical trials, stratified according to surgical risk scores.*

*Transcatheter Treatment of Aortic Valve Disease Clinical and Technical Aspects DOI: http://dx.doi.org/10.5772/intechopen.105860*

#### **Figure 2.**

*Management of patients with aortic stenosis [13].*

SAVR for younger patients who are low risk for surgery (<75 years and STS-PROM/ EuroSCORE II <4%) or in patients who are operable and unsuitable for transfemoral TAVI, leaving gray-zone context to the comprehensive evaluation of individual clinical, anatomical, and procedural factors by the Heart Team, which discussion is however recommended in every scenario [13].
