Moderate aortic stenosis: diagnostic pitfalls and the role of multimodality imaging in risk stratification and clinical management.

BACKGROUND: Moderate aortic stenosis (AS) has traditionally been considered a transitional and relatively benign stage of valvular disease. Yet, contemporary evidence shows that it is associated with substantial morbidity and mortality even before progression to severe AS. This paper synthesizes current evidence on the limitations of standard echocardiography, highlights the role of advanced imaging and artificial intelligence, and outlines evolving strategies for risk stratification and clinical management. Multimodality imaging provides a more accurate assessment of disease severity beyond conventional echocardiographic parameters: computed tomography aortic valve calcium scoring, cardiac magnetic resonance, and 18 F-sodium fluoride positron emission tomography reveal early myocardial injury and identify rapid progressors. AI further enhances reproducibility and supports the development of emerging prognostic models. A staging approach that integrates ventricular, atrial, and right-sided involvement correlates more closely with clinical outcomes than valve metrics alone, enabling a more comprehensive characterization of disease burden. Although guideline-directed surveillance remains the standard strategy for most patients, selected high-risk individuals, particularly those with adverse remodeling, elevated biomarkers, or recurrent heart failure admissions, may benefit from earlier intervention. SHORT CONCLUSION: While waiting for the results of ongoing randomized trials cardiologist should implement all the imaging multimodality tools available in order to individuate patients in which an earlier treatment of moderate AS will more probably improve long-term outcomes.