Threshold effect for lipoprotein(a) in aortic stenosis

Latest Advances in Multimodality Imaging of Aortic Stenosis

Aortic stenosis is a common condition associated with major morbidity, mortality, and health-care costs. Nevertheless, we currently lack any effective medical therapies that can treat or prevent disease development or progression. Modern advances in echocardiography and CT have helped improve the assessment of aortic stenosis severity and monitoring of disease progression, whereas cardiac MRI informs on myocardial health and the development of fibrosis. In a series of recent studies, 18F-NaF PET/CT has been shown to assess valvular disease activity and progression, providing mechanistic insights that can inform potential novel therapeutic approaches. This review will examine the latest advances in the imaging of aortic stenosis and bioprosthetic valve degeneration and explore how these techniques can assist patient management and potentially accelerate novel therapeutic developments.

Calcific aortic valve disease: from molecular and cellular mechanisms to medical therapy

Calcific aortic valve disease (CAVD) is a highly prevalent condition that comprises a disease continuum, ranging from microscopic changes to profound fibro-calcific leaflet remodelling, culminating in aortic stenosis, heart failure, and ultimately premature death. Traditional risk factors, such as hypercholesterolaemia and (systolic) hypertension, are shared among atherosclerotic cardiovascular disease and CAVD, yet the molecular and cellular mechanisms differ markedly. Statin-induced low-density lipoprotein cholesterol lowering, a remedy highly effective for secondary prevention of atherosclerotic cardiovascular disease, consistently failed to impact CAVD progression or to improve patient outcomes. However, recently completed phase II trials provide hope that pharmaceutical tactics directed at other targets implicated in CAVD pathogenesis offer an avenue to alter the course of the disease non-invasively. Herein, we delineate key players of CAVD pathobiology, outline mechanisms that entail compromised endothelial barrier function, and promote lipid homing, immune-cell infiltration, and deranged phospho-calcium metabolism that collectively perpetuate a pro-inflammatory/pro-osteogenic milieu in which valvular interstitial cells increasingly adopt myofibro-/osteoblast-like properties, thereby fostering fibro-calcific leaflet remodelling and eventually resulting in left ventricular outflow obstruction. We provide a glimpse into the most promising targets on the horizon, including lipoprotein(a), mineral-binding matrix Gla protein, soluble guanylate cyclase, dipeptidyl peptidase-4 as well as candidates involved in regulating phospho-calcium metabolism and valvular angiotensin II synthesis and ultimately discuss their potential for a future therapy of this insidious disease.