Right Atrial Remodeling and Outcome in Patients with Secondary Tricuspid Regurgitation

ABSTRACT

Background

In patients with secondary tricuspid regurgitation (STR), right atrial remodeling (RAR) is a proven marker of disease progression. However, the prognostic value of RAR, assessed by indexed RA volume (RAVi) and reservoir strain (RAS) remains to be clarified. Accordingly, the aim of our study is to investigate the association with outcome of RAR in patients with STR.

Methods

We enrolled 397 patients (44% men, 72.7±13 years) with mild to severe STR. Complete two-dimensional and speckle-tracking echocardiography analysis of RA and right ventricular (RV) size and function were obtained in all patients. The primary endpoint was the composite of death from any cause and heart failure (HF) hospitalization.

Results

After a median follow-up of 15 months (IQR: 6-23), the endpoint was reached by 158 patients (39%). Patients with RAS <13% and RAVi >48 mL/m² had significantly lower survival rates compared to patients with RAS ≥13% and RAVi ≤48 mL/m² (log rank p<0.001). On multivariable analysis, RAS <13% (HR 2.11; 95% CI, 1.43-3.11; p<0.001) and RAVi >48mL/m² (HR 1.49; 95% CI, 1.01-2.18; p=0.04) remained associated with the combined endpoint, even after adjusting for RV free-wall longitudinal strain (RV-FWLS), significant chronic kidney disease, and NYHA class. STR excess mortality increased exponentially with values of 18.2% and 51.3 mL/m² for RAS and RAVi, respectively. In nested models, the addition of RAS and RAVi provided incremental prognostic value over clinical, conventional echocardiographic parameters of RV size and function, and RV-FWLS.

Conclusions

In patients with STR, RAR was independently associated with mortality and HF hospitalization. Assessment of RAR could improve risk stratification of patients with STR, potentially identifying those who may benefit from optimization of medical therapy and a closer follow up.