Hippocampal blood flow abnormality associated with depressive symptoms and cognitive impairment in patients with chronic heart failure

Background: Depressive symptoms and memory impairment are prevalent in patients with chronic heart failure (CHF). Although the mechanisms remain to be elucidated, the hippocampus (an important brain area for emotion and memory) may be a possible neural substrate for these symptoms. Methods and Results: We prospectively enrolled 40 Stage C patients, who had past or current CHF symptoms, and as controls 40 Stage B patients, who had structural heart disease but had never had CHF symptoms, in Brain Assessment and Investigation in Heart Failure Trial (B-HeFT) (UMIN000008584). As the primary index, we measured cerebral blood flow (CBF) in the 4 anterior-posterior segments of the hippocampus, using brain MRI analysis. Depressive symptoms, immediate memory (IM) and delayed memory (DM) were assessed using Geriatric Depression Scale (GDS), and Wechsler Memory Scale-revised (WMS-R), respectively. Hippocampus CBF in the most posterior segment was significantly lower in Stage C than in Stage B group (P=0.029 adjusted for Holm’s method). Multiple regression analysis identified significant association between hippocampus CBF and GDS or DM score in Stage C group (all P<0.05). GDS score was significantly higher, and IM and DM scores were lower in Stage C patients with hippocampus CBF below the median than those with hippocampus CBF above the median (all P<0.05). Conclusions: Hippocampus abnormalities are associated with depressive symptoms and cognitive impairment in CHF patients.