Background: The prognostic importance of left atrial (LA) dysfunction is increasingly recognized. Magnetic Resonance Imaging (MRI) can provide excellent visualization of the left atrial wall. We aimed to study the association of LA dysfunction measured using feature-tracking MRI with incident adverse cardiovascular events among subjects with or without HF at baseline. Methods and Results: We prospectively studied 640 adults without HF (n=419), HF with preserved ejection fraction (HFpEF, n=101), or HF with reduced ejection fraction (HFrEF, n=120). We measured phasic LA function by volumetric and feature-tracking methods to derive longitudinal strain. The composite outcome of incident heart failure hospitalization or death was adjudicated over a median follow-up of 37.1 months. Measures of LA phasic function were more prominently impaired in subjects with HFrEF, than among subjects with HFpEF. 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, heart failure status, maximum LA volume, left ventricular (LV) mass and LV 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 HR=1.59; 95%CI=1.16–2.16, P=0.0035), and reservoir strain (Standardized HR=0.68; 95%CI=0.52–0.89, P=0.0055). Conclusions: Phasic LA function measured using MRI feature-tracking is independently predictive of the risk of incident HF admission or death, even after adjusting for LA volume and LV remodeling.

CKD is associated with increased (inactive) dp-ucMGP, a vitamin K-dependent inhibitor of vascular calcification, which correlates with large artery stiffness. Further studies are needed to assess whether vitamin K2 supplementation represents a suitable therapeutic strategy to prevent or reduce arterial stiffening in CKD.