Right Atrial Phasic Function in Heart Failure With Preserved and Reduced Ejection Fraction.

OBJECTIVES: This study researched right atrial (RA) deformation indexes and their association with all-cause mortality among subjects with or without heart failure (HF). BACKGROUND: Although left atrial dysfunction is well described in HF, patterns of RA dysfunction and their prognostic implications are unclear. Cardiac magnetic resonance (CMR) imaging can provide excellent visualization of the RA. We used CMR to characterize RA phasic function in HF and to assess its prognostic implications. METHODS: This study prospectively examined 608 adults without HF (n = 407), as well as adults with HF with a reduced ejection fraction (HFrEF) (n = 105) or with HF with a preserved ejection fraction (HFpEF) (n = 96). Phasic RA function was measured via volume measurements and feature-tracking methods to derive longitudinal strain. All-cause death was ascertained over a median follow-up of 38.9 months. Standardized hazard ratios (HRs) were computed via Cox regression. RESULTS: Measures of RA phasic function were more prominently impaired in subjects with HFrEF than those in subjects with HFpEF. In analyses that adjusted for demographic factors, HF status, left ventricular ejection fraction, right ventricular end-diastolic volume index, and right ventricular ejection fraction, RA reservoir strain (HR: 0.66; 95% confidence interval [CI]: 0.47 to 0.92; p = 0.0154), RA expansion index (HR: 0.53; 95% CI: 0.31 to 0.91; p = 0.0116), RA conduit strain (HR: 0.58; 95% CI: 0.40 to 0.84; p = 0.0039), and RA conduit strain rate (HR: 1.51; 95% CI: 1.02 to 2.220; p = 0.0373) independently predicted all-cause mortality. In contrast, RA booster pump function and RA volume index did not independently predict the risk of death. CONCLUSIONS: Phasic RA function is predictive of the risk of all-cause death in a diverse group of subjects with and without HF. RA conduit and reservoir function are independent predictors of mortality.

Left Atrial Phasic Function by Cardiac Magnetic Resonance Feature Tracking Is a Strong Predictor of Incident Cardiovascular Events.

BACKGROUND: The prognostic importance of left atrial (LA) dysfunction is increasingly recognized. Magnetic resonance imaging can provide excellent visualization of the LA wall. We aimed to study the association of LA dysfunction measured using feature-tracking magnetic resonance imaging with incident adverse cardiovascular events among subjects with or without heart failure (HF) at baseline. METHODS AND RESULTS: We prospectively studied 640 adults without HF (n=419), HF with preserved ejection fraction (n=101), or HF with reduced ejection fraction (n=120). We measured phasic LA function by volumetric and feature-tracking methods to derive longitudinal strain. The composite outcome of incident HF hospitalization or death was adjudicated during a median follow-up of 37.1 months. Measures of LA phasic function were more prominently impaired in subjects with HF with reduced ejection fraction than among subjects with HF with preserved ejection fraction. In unadjusted Cox proportional hazards models, all measures of phasic LA function and volumes (maximum, minimum, and diastatic) were associated with the composite outcome. However, in analyses that adjusted for clinical risk factors, HF status, maximum LA volume, left ventricular mass, and left ventricular ejection fraction, measures of conduit and reservoir LA function, but not booster-pump function, were associated with the composite outcome. The strongest associations were observed for conduit longitudinal strain (standardized hazard ratio, 0.66; 95% CI, 0.49-0.88; P=0.004), conduit strain rate (standardized hazard ratio, 1.59; 95% CI, 1.16-2.16; P=0.0035), and reservoir strain (standardized hazard ratio, 0.68; 95% CI, 0.52-0.89; P=0.0055). CONCLUSIONS: Phasic LA function measured using magnetic resonance imaging feature tracking is independently predictive of the risk of incident HF admission or death, even after adjusting for LA volume and left ventricular remodeling.