Right Ventricular Function in Patients With Significant Tricuspid Regurgitation.

Significant tricuspid regurgitation (TR) is increasingly recognized as a major determinant of morbidity and mortality, yet the clinical impact of significant TR has long been underestimated. Assessment of right ventricular (RV) systolic function is central to understanding and managing TR and represents the principal determinant of symptoms, therapeutic response, and long-term outcomes. The unique sensitivity of the RV to alterations in preload and afterload leads to maladaptive remodeling, making accurate functional assessment essential for risk stratification and for optimizing the timing and type of intervention, especially given the expanding range of available surgical and transcatheter treatment options. Echocardiography remains the primary imaging modality, providing qualitative and quantitative evaluations of RV function through parameters such as tricuspid annular plane systolic excursion (TAPSE), RV fractional area change (RVFAC), and tissue Doppler systolic velocity (S'). Advances in speckle-tracking echocardiography for RV free-wall longitudinal strain and in three-dimensional imaging have improved accuracy; however, all echocardiographic measures remain limited by the complex geometry of the RV. When feasible and available, cardiac magnetic resonance (CMR) imaging serves as the reference standard for precise assessment of RV volumetric and functional parameters. Impaired RV systolic function, both before and after intervention, irrespective of the imaging parameter used for the assessment, consistently predicts adverse outcomes in patients with severe TR, including heart failure progression, reduced exercise tolerance, and decreased survival. Therefore, early recognition and quantification of RV dysfunction are crucial to enable timely therapy, as interventions before the development of advanced RV impairment provide symptomatic and survival benefits. This review summarizes the pathophysiology, quantitative thresholds, and prognostic significance of RV function assessment, emphasizing the pivotal role this evaluation plays in the contemporary management of significant TR.