Abstract
Mitral regurgitation (MR) is one of the most prevalent valvular disorders worldwide, with a growing burden driven by population aging and improved diagnostic capabilities. Understanding the mechanism of MR, whether primary, due to intrinsic valve abnormalities, or secondary, resulting from atrial or ventricular remodeling, is essential for optimal management. Echocardiography, particularly advanced modalities such as three-dimensional imaging and strain analysis, plays a central role in this process. It allows accurate quantification of MR severity, detailed characterization of valve and ventricular anatomy, and assessment of remodeling, all of which are critical for determining the optimal timing for intervention. Beyond diagnosis, echocardiography is indispensable in guiding therapy selection: it informs surgical planning by defining leaflet pathology for repair versus replacement strategies, and directs transcatheter interventions by guiding interatrial septal puncture, catheter orientation, and device deployment in real time. While surgery remains the gold standard for primary MR, transcatheter approaches including edge-to-edge repair and emerging mitral valve replacement are increasingly relevant, particularly in patients at high surgical risk or with complex anatomy. This review emphasizes the pivotal role of echocardiography in the pre-procedural assessment of MR, highlighting its ability to integrate anatomical, functional, and hemodynamic information to guide patient-tailored therapeutic strategies and optimize outcomes within a Heart Team framework.