Right Atrial Volume Index in Chronic Systolic Heart Failure and Prognosis

Objectives: The aim of this study was to determine the relationship between right atrial volume index (RAVI) and right ventricular (RV) systolic and diastolic function, as well as long-term prognosis in patients with chronic systolic heart failure (HF).

Background: RV dysfunction is associated with poor prognosis in patients with HF, although echocardiographic assessment of RV systolic and diastolic dysfunction is challenging. The ability to visualize the RA allows a quantitative, highly reproducible assessment of the RA volume that can be indexed to body surface area.

Methods: The ADEPT (Assessment of Doppler Echocardiography for Prognosis and Therapy) trial enrolled 192 subjects with chronic systolic HF (left ventricular ejection fraction [LVEF] <or=35%). The RA volume was calculated by Simpson's method using single-plane RA area and indexed to body surface area (RAVI). RV systolic function was graded as normal, mild, mild-moderate, moderate, moderately severe, or severe dysfunction.

Results: In our study cohort, the mean RAVI was 28 +/- 15 ml/m(2), and increased with worsening RV systolic dysfunction, LVEF, and LV diastolic dysfunction (Spearman's r = 0.61, r = 0.26, and r = 0.51, respectively; p < 0.001 for all). RAVI correlated modestly with echocardiographic estimates of RV diastolic dysfunction, including tricuspid early/late velocities ratio (Spearman's r = 0.34, p < 0.0001), hepatic vein systolic/diastolic ratio (Spearman's r = -0.26, p < 0.001) but not tricuspid early/tricuspid annular early velocities ratio (E/Ea) (Spearman's r = 0.12, p = 0.11). Increasing tertiles of RAVI were predictive of death, transplant, and/or HF hospitalization (log-rank p = 0.0002) and remained an independent predictor of adverse clinical events after adjusting for age, B-type natriuretic peptide, LV ejection fraction, RV systolic dysfunction, and tricuspid E/Ea ratio (hazard ratio: 2.00, 95% confidence interval: 1.15 to 3.58, p = 0.013).

Conclusions: In patients with chronic systolic HF, RAVI is a determinant of right-sided systolic dysfunction. This quantitative and reproducible echocardiographic marker provides independent risk prediction of long-term adverse clinical events.