Moderate Symptomatic Aortic Stenosis: A New Trigger Point for Transcatheter Aortic Valve Replacement?

As of today, international guidelines recommend that aortic valve replacement may be considered in patients with moderate aortic stenosis (AS) only if an indication for coronary revascularization is present. 1 Vahanian A Beyersdorf F Praz F Milojevic M Baldus S Bauersachs J Capodanno D Conradi L De Bonis M De Paulis R Delgado V Freemantle N Gilard M Haugaa KH Jeppsson A Jüni P Pierard L Prendergast BD Sádaba JR Tribouilloy C Wojakowski W ESC/EACTS Scientific Document Group2021 ESC/EACTS Guidelines for the management of valvular heart disease [published correction appears in Eur Heart J 2022;43:2022]. Eur Heart J. 2022; 43: 561-632 Google Scholar Nevertheless, moderate AS has been linked to an increased risk of cardiovascular events and mortality in recent observational studies. 2 Strange G Stewart S Celermajer D Prior D Scalia GM Marwick T Ilton M Joseph M Codde J Playford D National Echocardiography Database of Australia contributing sitesPoor long-term survival in patients with moderate aortic stenosis. J Am Coll Cardiol. 2019; 74: 1851-1863 Google Scholar Whether the latter finding is caused by moderate AS itself, a rapid progression to severe AS, or associated co-morbidities (i.e., moderate AS is a marker of greater clinical baseline risk) remains to be established. Recent literature has highlighted that AS is not only a disease of the aortic valve but also of the left ventricle (LV), with multiple cardiac magnetic resonance studies indicating the presence of LV midwall fibrosis in patients with moderate AS as a marker of worse prognosis, even in the setting of preserved LV ejection fraction. 3 Amanullah MR Pio SM Ng ACT Sin KYK Marsan NA Ding ZP Leon MB Généreux P Delgado V Ewe SH Bax JJ. Prognostic implications of associated cardiac abnormalities detected on echocardiography in patients with moderate aortic stenosis. JACC Cardiovasc Imaging. 2021; 14: 1724-1737 Google Scholar However, whether interventional treatment (surgical or percutaneous) can improve outcomes in patients with moderate AS over medical therapy is currently not known (Figure 1).