Heart Failure and Moderate Aortic Stenosis: is Early TAVI the Better Strategy?

Aortic stenosis (AS) is the most common valvular heart disease in Western countries. Current clinical guidelines recommend intervention exclusively for severe AS, given its association with poor short-term prognosis. However, accumulating evidence over recent years suggests that even moderate AS may be associated with adverse outcomes, particularly in patients with heart failure with reduced ejection fraction (HFrEF). Consequently, an early aortic valve replacement (AVR) strategy could potentially improve survival and reduce heart-failure-related hospitalizations. Moreover, treating moderate AS in patients with HFrEF may reduce left ventricular afterload and improve haemodynamic status, thereby facilitating the initiation and/or up-titration of guideline-directed medical therapy (GDMT), especially when such therapy is poorly tolerated due to hypotension or other hypoperfusion-related factors. Nevertheless, the available evidence is derived predominantly from retrospective observational studies. The only published randomized controlled trial to date (the TAVR UNLOAD trial) failed to demonstrate a prognostic benefit of transcatheter aortic valve implantation (TAVI) in patients with moderate AS and HFrEF or heart failure with mildly reduced ejection fraction (HFmrEF). Two additional ongoing randomized trials may ultimately provide more definitive evidence. In summary, although the pathophysiological rationale is sound and the available data are encouraging, an early AVR strategy in moderate AS cannot currently be regarded as evidence-based.