Cardiac dysfunction is associated with indices of brain atrophy and cognitive impairment in heart failure with reduced ejection fraction.

Abstract

Cardiac dysfunction in heart failure with reduced ejection fraction (HFrEF) may contribute to brain atrophy and cognitive decline beyond that which is typical of healthy ageing. This study tested the hypothesis that HFrEF would be associated with regionally-unique brain remodelling and impaired cognitive performance independent of age. Further, that cardiac index and clinical markers of HFrEF severity would predict brain remodelling and cognition with age and HFrEF, respectively. Cardiac function and brain morphology were assessed using magnetic resonance imaging in young healthy adults (24±6y), older healthy adults (60±6y) and patients living with HFrEF (59±6y). The Montreal Cognitive Assessment was administered to assess cognition. Gray matter volume (GMV) (young: 492±24, old: 456±24, HFrEF: 433±32cm³, P≤0.05) and cortical thickness (young: 2.44±0.07, old: 2.33±0.08, HFrEF: 2.22±0.10mm, P<0.01) were lower with age and lowered further with HFrEF. Regional analysis revealed a unique pattern of atrophy with HFrEF. Whereas age had little effect on cortical curvature (P=0.60), it was greater in HFrEF (young: 0.127±0.003, old: 0.128±0.003, HFrEF: 0.136±0.005mm^-1, P<0.01). Cardiac index was the best correlate of brain atrophy and cognitive performance with age (R=0.33-0.47; P<0.05). However, EF and end systolic volume index were better correlates of brain atrophy and cognitive performance in HFrEF (R=-0.50-0.49; P≤0.05). These data indicate that lower GMV and cortical thickness in HFrEF are not merely an acceleration of age-related declines but reflect a unique pattern of brain atrophy and remodelling. Additionally, classic markers of HF severity may be better predictors of pathological brain remodelling than reduced cardiac index.