Multimodality Imaging Markers of Adverse Myocardial Remodeling in Aortic Stenosis

Aortic stenosis (AS) causes left ventricular remodeling (hypertrophy, remodeling, fibrosis) and other cardiac changes (left atrial dilatation, pulmonary artery and right ventricular changes). These changes, and whether they are reversible (reverse remodeling), are major determinants of timing and outcome from transcatheter or surgical aortic valve replacement. Cardiac changes in response to AS afterload can either be adaptive and reversible, or maladaptive and irreversible, when they may convey residual risk after intervention. Structural and hemodynamic assessment of AS therefore needs to evaluate more than the valve, and, in particular, the myocardial remodeling response. Imaging plays a key role in this. This review assesses how multimodality imaging evaluates AS myocardial hypertrophy and its components (cellular hypertrophy, fibrosis, microvascular changes, and additional features such as cardiac amyloid) both before and after intervention, and seeks to highlight how care and outcomes in AS could be improved. (C) 2019 by the American College of Cardiology Foundation.