Altes A, et al. - In a prospective cohort of HF-rEF patients in sinus rhythm receiving cardiac resynchronization therapy (CRT), researchers assessed the association between right atrium [RA] volume (RAV) and long-term mortality. Study participants included 172 patients. Using Simpson's method, the right atrium volume index (RAVI) was calculated from the apical four-chamber view and indexed to body surface area. In patients with HFrEF in sinus rhythm receiving CRT, RA enlargement is a powerful and highly reproducible independent predictor of long-term mortality. Compared to patients with RAVI≤29 mL/m², those in the highest tertile (RAVI > 29 ml/m²) had significantly greater risk of death.