Developing Insights Regarding Tricuspid Valve Regurgitation: Morphology, Assessment of Severity, and the Need for a Novel Grading Scheme

Current understanding that progressive tricuspid regurgitation (TR) is associated with worse outcomes has highlighted the clinical need for a more accurate assessment of TR morphology and severity. This need has been further emphasized owing to the development of a myriad of percutaneous right-sided interventions, which may offer successful treatment of TR in selected patients. Understanding the etiology and quantification of the severity of TR has important implications in the selection of novel therapeutic strategies, i.e., medical vs. percutaneous vs. surgical approaches. Newer grading schemas that better reflect the TR lesion severity have been recently proposed and may facilitate monitoring of the evolution of TR following percutaneous and/or surgical treatment. In this review, we summarize contemporary concepts regarding tricuspid valve morphology, TR etiology, and associated mechanisms and echocardiographic approaches to grade TR severity.