Unmet Needs in the Assessment of Right Ventricular Function for Severe Tricuspid Regurgitation.

Tricuspid regurgitation (TR) is a highly prevalent valvular heart disease that has been long overlooked, but lately its independent association with adverse cardiovascular outcomes was recognized. The time point to intervene and repair the tricuspid valve is defined by the right ventricular (RV) dilation and dysfunction that comes up at a later stage. While guidelines favor tricuspid valve repair before severe RV dysfunction ensues, the definition of RV dysfunction in a universal manner remains vague. As a result, the candidates for transcatheter or surgical TR procedures are often referred late, when advanced RV dysfunction is established, and any derived procedural survival benefit is attenuated. Thus, it is of paramount importance to establish a universal means of RV function assessment in patients with TR. Conventional echocardiographic indices of RV function routinely applied have fundamental flaws that limit the precise characterization of RV performance. More recently, novel echocardiographic indices such as strain via speckle-tracking have emerged, demonstrating promising results in the identification of early RV damage. Additionally, evidence of the role of alternative imaging modalities such as cardiac computed tomography and cardiac magnetic resonance, for RV functional assessment in TR, has recently arisen. This review provides a systematic appraisal of traditional and novel multimodality indices of RV function in severe TR and aims to refine RV function assessment, designate future directions, and ultimately, to improve the outcome of patients suffering from severe TR.