Determinants of outcome in atrial functional tricuspid regurgitation

Abstract Background Atrial functional tricuspid regurgitation (AFTR) is increasingly recognized as a result of atrial remodelling in patients with atrial fibrillation (AF). However, prognostic predictors in this population remain incompletely defined. Objectives To evaluate echocardiographic characteristics and identify predictors of all-cause mortality in patients with AFTR. Methods We retrospectively studied consecutive patients with AF who underwent transthoracic echocardiography between 2017 and 2025. Inclusion required significant right atrial remodelling, defined as a right atrial area > 25 cm 2 . Patients with at least moderate functional tricuspid regurgitation comprised the AFTR cohort, while patients with mild/trivial/no tricuspid regurgitation served as controls. Patients with primary valvular disease, cardiomyopathy, congenital heart disease, device-related valve disease, RV dilatation, or more than mild RV systolic dysfunction were excluded. Cox proportional hazards regression was performed to identify predictors of mortality. Results A total of 152 patients were included, comprising 120 patients with AFTR and 32 controls. Compared with controls, patients with AFTR demonstrated larger atrial dimensions, higher right-sided hemodynamic-burden, impaired RV longitudinal strain, and reduced reservoir RA strain. During a median follow-up of 6.3 years, 53 deaths (45%) occurred among patients with AFTR. In univariable Cox analysis, age (HR 1.02, 95% CI 1.00-1.04; p = 0.016), TR Vmax (HR 1.59, 95% CI 1.07–2.35; p = 0.020), and lower reservoir RA strain (HR 0.90, 95% CI 0.84–0.96; p = 0.003) were associated with mortality. In multivariable analysis, reservoir RA strain remained independently associated with mortality (adjusted HR 0.88, 95% CI 0.81–0.95; p < 0.001). Conclusion AFTR is characterized by marked biatrial remodelling and impaired right atrial function. Reduced RA reservoir strain was independently associated with mortality, supporting a potential role for RA deformation imaging in risk stratification in AFTR.