Abstract 713: Right Atrial Ejection Fraction and Right Atrial Functional Index Predict Outcomes in Ambulatory Patients With Coronary Artery Disease: Findings From the Heart and Soul Study
Background: Right atrial (RA) function has been little studied; therefore, we sought to estimate the magnitude of its contribution to overall cardiac status through measuring its influence on outcomes. We measured RA function as an empting fraction and as a function index and compared the magnitude of impairment in RA function by each measure with its impact on clinical outcomes.
Methods: We performed transthoracic echocardiography in 944 ambulatory patients with CAD who were free of mitral stenosis and atrial fibrillation. Right atrial function was reported as RA ejection fraction (RAEF = RAESV-RAEDV/RAESV) and as RA functional index (RAFI = RAEF × PV VTI/RAESVI), as has been reported for left atrial function. Outcomes were defined as all-cause mortality and CHF hospitalizations. We divided participants by deciles of RAEF and RAFI and used proportional hazards models to compare the risk of developing HF or death in patients according to RAEF and RAFI.
Results: Participants with RAEF and RAFI in the lowest quartile were more likely to develop HF or die during 5.2 years of follow-up than those with RAEF or RAFI in the other deciles (Figure⇓). When entered as continuous variables in age-adjusted models, the c-statistic for predicting HF or death for RAEF (.67) was similar to LAEF (.68, p=0.56). However, the c-statistic for predicting HF or death for RAFI (.68) was lower than LAFI (.71, p=0.01).
Conclusions: 1 - RAEF and RAFI are independent predictors of CHF hospitalizations and all-cause mortality. 2 - RA function can be easily measured and provides meaningful prognostic information.