Asymptomatic severe aortic stenosis: what do we know and where we are going?

Take Home Messages
  • 1/3 of patients with severe aortic stenosis are asymptomatic
  • Timing of aortic valve replacement is critical to balance irreversible myocardial damage and sudden cardiac death against short and long-term intervention complications
  • This review highlights multiple features that should alert the clinician of a patient at high risk of progression or poor long-term prognosis
  • Numerous ongoing studies are aimed at making a paradigm shift in the management of this challenging cohort

Valvular heart disease (VHD) is increasing in incidence (1) and it is expected that the number of patients affected is due to double by 2046. Aortic stenosis (AS) is the most common valvular lesion requiring intervention (2) in the United Kingdom (UK) and Europe, even in the pre-transcatheter aortic valve replacement (TAVR) era. In the UK from 2018-2019 there were >10,000 TAVR or isolated surgical aortic valve replacements (SAVR), of which TAVR has now surpassed SAVR (3).

AS is often caused by progressive fibro-calcific thickening and remodelling of the aortic valve (AV) leaflets that leads to restriction and obstruction (4). This subsequently induces increased afterload on the left ventricle (LV) and LV hypertrophy. This initially adaptive response eventually decompensates resulting in heart failure and death.

The prognosis of symptomatic severe AS is dire, with a 1-year mortality of ~50% (5). At present there are no medications that ameliorate the disease progress, therefore timely valve replacement is essential for long term survival.

With regards to the management of asymptomatic AS, there is debate around the timing of AVR. Intervention should ideally take place when the risks of the disease process (irreversible myocardial damage and sudden cardiac death (SCD)) outweigh the periprocedural and long-term complications from intervention. This editorial will discuss the high-risk features of asymptomatic severe AS and future research aimed at optimising outcomes in this group.