Abstract 9116: Overlap Between Cognitive Brain Damage and Reduced Cerebral Blood Flow in Heart Failure

Abstract

Heart failure (HF) subjects show reduced cerebral blood flow (CBF) in brain sites that control autonomic and cognitive functions. Brain structural injury also emerges in cognitive and autonomic control sites; however, it is unclear whether brain sites with reduced CBF overlap areas with structural brain injury. METHODS: We collected Diffusion Tensor Imaging (DTI) data from 9 HF (age, 54.6±10.4 years; BMI, 30.5±5.4 kg/m2; LVEF, 31.3±7.8, 6 male) and 7 control subjects (age, 53.7±3.1 years; BMI, 25.9±3.0 kg/m2, 6 male) using a 3.0 Tesla MRI scanner, and assessed regional brain injury and overlap with CBF changes. Using DTI data, whole brain mean diffusivity (MD) maps were calculated, normalized to a common space, and smoothed. The normalized and smoothed MD maps were compared voxel-by-voxel between HF and controls using ANCOVA (p = 0.005), with age and gender as covariates. The brain clusters with significantly increased MD values, indicative of brain injury, were overlaid onto background images. The brain clusters with significantly reduced regional CBF values were also overlaid onto background images. Both findings were compared region-by-region for overlap in structural injury and CBF changes. RESULTS: Multiple brain areas in HF subjects (Figure), including the right insular lobe (a), right hippocampus (b), and midline pons (c) showed overlap in structural injury and CBF changes (ANCOVA p=0.005; group comparisons in Table). CONCLUSIONS: HF subjects show brain sites with overlap in structural injury and CBF changes in autonomic and cognitive regulatory areas. The findings indicate that reduced CBF may contribute to structural injury in those sites.