Link between change in cognition and left ventricular function following cardiac resynchronization therapy

Is it time for Heart-Brain clinics? A clinical survey and proposition to improve current care for cognitive problems in heart failure

BACKGROUND

Cognitive impairment is highly prevalent among patients with heart failure (HF). International guidelines on the management of HF recommend screening for cognitive impairment and tailored care for patients with cognitive impairment. However, practical guidance is lacking. In this study, we explore cardiologists' perspective on screening and care for cognitive impairment in patients with HF. We give an example of a multidisciplinary Heart-Brain care pathway that facilitates screening for cognitive impairment in patients with HF.

METHODS

We distributed an online survey to cardiologists from the Dutch working groups on Geriatric Cardiology and Heart Failure. It covered questions about current clinical practice, impact of cognitive impairment on clinical decision-making, and their knowledge and skills to recognize cognitive impairment.

RESULTS

Thirty-six out of 55 invited cardiologists responded. Only 3% performed structured cognitive screening, while 83% stated that not enough attention is paid to cognitive impairment. More than half of the cardiologists desired more training in recognizing cognitive impairment and three-quarters indicated that knowing about cognitive impairment would change their treatment plan. Eighty percent agreed that systematic cognitive screening would benefit their patients and 74% wished to implement a Heart-Brain clinic. Time and expertise were addressed as the major barriers to screening for cognitive impairment.

CONCLUSION

Although cardiologists are aware of the clinical relevance of screening for cognitive impairment in cardiology patients, such clinical conduct is not yet commonly practiced due to lack of time and expertise. The Heart-Brain care pathway could facilitate this screening, thus improving personalized care in cardiology.

A Correlative Relationship Between Heart Failure and Cognitive Impairment: A Narrative Review

Heart failure (HF) is a chronic condition affecting millions of people worldwide. While the cardinal manifestations of HF are related to the cardiovascular system, it has become progressively evident that mild cognitive impairment (MCI) is also a significant complication of the disease. In fact, a significant number of patients with HF may experience MCI, which can manifest as deficits in attention, memory, executive function, and processing speed. The mechanisms responsible for cognitive dysfunction in HF are intricate and multifactorial. Possible factors contributing to this condition include decreased cerebral blood flow, thrombogenicity associated with HF, systemic inflammatory conditions, and proteotoxicity. MCI in HF has significant clinical implications, as it is linked to poorer quality of life, increased morbidity and mortality, and higher healthcare costs. Additionally, MCI can disrupt self-care behaviors, adherence to medication, and decision-making abilities, all of which are crucial for effectively managing HF. However, there is currently no gold standard diagnostic tool and follow-up strategy for MCI in HF patients. There is limited knowledge on the prevention and treatment of MCI. In conclusion, MCI is a common and clinically important complication of HF. Considering the substantial influence of MCI on patient outcomes, it is imperative for healthcare providers to be cognizant of this issue and integrate cognitive screening and management strategies into the care of HF patients.

Restoring myocardial infarction-induced long-term memory impairment by targeting the cystic fibrosis transmembrane regulator

BACKGROUND

Cognitive impairment is a serious comorbidity in heart failure patients, but effective therapies are lacking. We investigated the mechanisms that alter hippocampal neurons following myocardial infarction (MI).

METHODS

MI was induced in male C57Bl/6 mice by left anterior descending coronary artery ligation. We utilised standard procedures to measure cystic fibrosis transmembrane regulator (CFTR) protein levels, inflammatory mediator expression, neuronal structure, and hippocampal memory. Using in vitro and in vivo approaches, we assessed the role of neuroinflammation in hippocampal neuron degradation and the therapeutic potential of CFTR correction as an intervention.

FINDINGS

Hippocampal dendrite length and spine density are reduced after MI, effects that associate with decreased neuronal CFTR expression and concomitant microglia activation and inflammatory cytokine expression. Conditioned medium from lipopolysaccharide-stimulated microglia (LCM) reduces neuronal cell CFTR protein expression and the mRNA expression of the synaptic regulator post-synaptic density protein 95 (PSD-95) in vitro. Blocking CFTR activity also down-regulates PSD-95 in neurons, indicating a relationship between CFTR expression and neuronal health. Pharmacologically correcting CFTR expression in vitro rescues the LCM-mediated down-regulation of PSD-95. In vivo, pharmacologically increasing hippocampal neuron CFTR expression improves MI-associated alterations in neuronal arborisation, spine density, and memory function, with a wide therapeutic time window.

INTERPRETATION

Our results indicate that CFTR therapeutics improve inflammation-induced alterations in hippocampal neuronal structure and attenuate memory dysfunction following MI.

FUNDING

Knut and Alice Wallenberg Foundation [F 2015/2112]; Swedish Research Council [VR; 2017-01243]; the German Research Foundation [DFG; ME 4667/2-1]; Hjärnfonden [FO2021-0112]; The Crafoord Foundation; Åke Wibergs Stiftelse [M19-0380], NMMP 2021 [V2021-2102]; the Albert Påhlsson Research Foundation; STINT [MG19-8469], Lund University; Canadian Institutes of Health Research [PJT-153269] and a Heart and Stroke Foundation of Ontario Mid-Career Investigator Award.

Education level may modify the association between cardiac index and cognitive function among elders with normal ejection function

Background

Lower cardiac index (CI) in elders has been associated with incident dementia, and higher CI has protectively effect with brain aging. In the present study, we investigated the modulating effects of education level and arterial stiffness on the association between CI and cognitive function among older adults.

Methods

A total of 723 elders (≥60 years, 50.1% women) with normal left ventricular ejection fraction (≥50%) were identified from the Cardiovascular Diseases Risk Factor Two-Township Study. CI was calculated from the Doppler-derived stroke volume. We evaluated arterial stiffness by measuring carotid-femoral pulse wave velocity (CFPWV) and global cognitive function by using the Mini-Mental Short Examination (MMSE). Education level was determined by years of formal education.

Results

In linear regression analysis adjusting for age, sex, formal years of education, and CFPWV, CI was significantly positively associated with MMSE (BETA=0.344±0.130, P = 0.0082). In logistic regression analysis adjusting for age, sex, formal years of education, and CFPWV, subjects with a CI≥75 percentile had a significantly lower risk of low MMSE (<26) (OR = 0.495, 95% CI = 0.274–0.896, P = 0.02). In subgroup analysis, higher CI was significantly associated with higher MMSE and lower risk of low MMSE only in elders with ≤ 9 years of formal education. Causal mediation analysis suggests that higher CI maintains higher MMSE in elders with lower education levels whereas higher CFPWV causes lower MMSE in all the elders.

Conclusion

In elders with normal ejection fraction, a higher CI was associated with a lower risk of cognitive function impairment, independent of arterial stiffness, mainly in subjects with a lower education level and possibly a smaller cognitive reserve.

Cognitive Dysfunction in Heart Failure: Pathophysiology and Implications for Patient Management

PURPOSE OF REVIEW

There is increasing recognition of the prevalence and impact of cognitive dysfunction (CD) in heart failure (HF) patients. This contemporary review appraises the evidence for epidemiological association, direct pathophysiological links and emerging pharmacological and non-pharmacological interventions. Furthermore, we present evidence for care models that aim to mitigate the morbidity and poor quality of life associated with these dual processes and propose future work to improve outcomes.

RECENT FINDINGS

CD disproportionately affects heart failure patients, even accounting for known comorbid risk factors, and this may extend to subclinical left ventricular dysfunction. Neuroimaging studies now provide evidence of anatomical and functional differences which support previously postulated mechanisms of reduced cerebral blood flow, micro-embolism and systemic inflammation. Interventions such as multidisciplinary ambulatory HF care, education and memory training improve HF outcomes perhaps to a greater degree in those with comorbid CD. Additionally, optimisation of standard heart failure care (cardiac rehabilitation, pharmacological and device therapy) may lead to additional cognitive benefits. Epidemiological, neuroimaging and intervention studies provide evidence for the causal association between HF and CD, although evidence for Alzheimer's dementia is less certain. Specific reporting of cognitive outcomes in HF trials and evaluation of targeted interventions is required to further guide care provision.

Cognitive decline in heart failure: Biomolecular mechanisms and benefits of exercise

By definition, heart failure (HF) is a human pathological condition affecting the structure and function of all organs in the body, and the brain is not an exception to that. Failure of the heart to pump enough blood centrally and peripherally is at the foundation of HF patients' inability to attend even the most ordinary daily activities and progressive deterioration of their cognitive capacity. What is more, between heart and brain exists a bidirectional relationship that goes well beyond hemodynamics and concerns bioelectric and endocrine signaling. This increasingly consolidated evidence makes the scenario even more complex. Studies have mainly chased how HF impairs cognition without focusing much on preventive measures, notably cardio-cerebral health proxies. Here, we aim to provide a brief account of known and hypothetical factors that may explain how exercise can help obviate cognitive dysfunction associated with HF in its different forms. As we shall see, there is a stringent need for a deeper grasp of such mechanisms. Indeed, gaining this new knowledge will automatically shed new light on the inner workings of HF itself, thus resulting in more effective prevention and treatment of this escalating syndrome.

Cognitive Impairment in Heart Failure: Landscape, Challenges, and Future Directions

Heart failure (HF) is a major global healthcare problem accounting for substantial deterioration of prognosis. As a complex clinical syndrome, HF often coexists with multi-comorbidities of which cognitive impairment (CI) is particularly important. CI is increasing in prevalence among patients with HF and is present in around 40%, even up to 60%, of elderly patients with HF. As a potent and independent prognostic factor, CI significantly increases the hospitalization and mortality and decreases quality of life in patients with HF. There has been a growing awareness of the complex bidirectional interaction between HF and CI as it shares a number of common pathophysiological pathways including reduced cerebral blood flow, inflammation, and neurohumoral activations. Research that focus on the precise mechanism for CI in HF is still ever insufficient. As the tremendous adverse consequences of CI in HF, effective early diagnosis of CI in HF and interventions for these patients may halt disease progression and improve prognosis. The current clinical guidelines in HF have begun to emphasize the importance of CI. However, nearly half of CI in HF is underdiagnosed, and few recommendations are available to guide clinicians about how to approach CI in patients with HF. This review aims to synthesize knowledge about the link between HF and cognitive dysfunction, issues pertaining to screening, diagnosis and management of CI in patients with HF, and emerging therapies for prevention. Based on data from current studies, critical gaps in knowledge of CI in HF are identified, and future research directions to guide the field forward are proposed.

Cerebral blood flow impairment and cognitive decline in heart failure

BACKGROUND AND PURPOSE

Cognitive decline is an important contributor to disability in patients with chronic heart failure, affecting 25%-50% of patients. The aim of this review is to stress the importance of understanding pathophysiological mechanisms of heart failure involved in cognitive decline.

METHODS

An extensive PubMed search was conducted for the literature on the basic mechanisms of cerebral blood flow regulation, the effect of cardiac dysfunction on cerebral blood flow, and possible mechanisms underlying the association between cardiac dysfunction and cognitive decline.

RESULTS

Published literature supports the thesis that cardiac dysfunction leads to cerebral blood flow impairment and predisposes to cognitive decline. One of the postulated mechanisms underlying cognitive decline in chronic heart failure is chronic regional hypoperfusion of critical brain areas. Cognitive function may be further compromised by microvascular damage due to cardiovascular risk factors. Furthermore, it is implied that cerebral blood flow assessment could enable early recognition of patients at risk and help guide appropriate therapeutic strategies.

CONCLUSION

Interdisciplinary knowledge in the fields of neurology and cardiology is essential to clarify heart and brain interconnections in chronic heart failure. Understanding and identifying the basic neuropathophysiological changes in chronic heart failure could help with developing methods for early recognition of patients at risk, followed by institution of therapeutic actions to prevent or decrease cognitive decline.

Cognitive impairment in heart failure: clinical implications, tools of assessment, and therapeutic considerations

Cognitive impairment (CI) is an important comorbidity in patients with heart failure (HF). Its prevalence parallels the severity of heart failure, while it is an independent prognostic marker of adverse events. Various factors contribute to cognitive decline in HF, influencing self-care. There are no standardized screening methods for the diagnosis and management of these patients. The aim of the present manuscript is to provide an overview of the impact of cognitive impairment in HF, describe the utility of assessment tools and imaging methods for the evaluation of CI, and propose a comprehensive diagnostic and management approach.

Testing influences of APOE and BDNF genes and heart failure on cognitive function

BACKGROUND

Apolipoprotein E (APOE) ε2, ε4 and brain-derived neurotrophic factor (BDNF) Val66Met alleles have been associated with cognition. Associations of these alleles with cognition in heart failure (HF) and influences of HF across the cognitive spectrum (i.e., cognitively normal to Alzheimer's dementia [AD]) remain unexplored.

OBJECTIVES

To investigate influences of APOE ε2, ε4, BDNF Met and HF on cognition among participants across the cognitive spectrum.

METHODS

Genetic association study using national databases (N = 7,166).

RESULTS

APOE ε2 frequencies were similar across the cognitive spectrum among participants with HF. APOE ε4 frequency was lower among participants with HF and AD than non-HF participants with AD. BDNF Met frequencies did not differ across the spectrum. HF was associated with worse attention and language. In the HF subsample, ε4 was associated with worse memory.

CONCLUSION

Associations between APOE and cognition may differ in HF but need to be tested in a larger sample.

Incident prolonged QT interval in midlife and late-life cognitive performance

BACKGROUND

Measures of cardiac ventricular electrophysiology have been associated with cognitive performance in cross-sectional studies. We sought to evaluate the association of worsening ventricular repolarization in midlife, as measured by incident prolonged QT interval, with cognitive decline in late life.

METHODS

Midlife QT interval was assessed by electrocardiography during three study visits from 1965/68 to 1971/74 in a cohort of Japanese American men aged 46-68 at Exam 1 from the Honolulu Heart Study. We defined incident prolonged QT as the QT interval in the upper quartile at Exam 2 or 3 after QT interval in lower three quartiles at Exam 1. Cognitive performance was assessed at least once using the Cognitive Abilities Screening Instrument (CASI), scored using item response theory (CASI-IRT), during four subsequent visits from 1991/93 to 1999/2000 among 2,511 of the 4,737 men in the Honolulu-Asia Aging Study otherwise eligible for inclusion in analyses. We used marginal structural modeling to determine the association of incident prolonged QT with cognitive decline, using weighting to account for confounding and attrition.

RESULTS

Incident prolonged QT interval in midlife was not associated with late-life CASI-IRT at cognitive baseline (estimated difference in CASI-IRT: 0.04; 95% CI: -0.28, 0.35; p = 0.81), or change in CASI-IRT over time (estimated difference in annual change in CASI-IRT: -0.002; 95%CI: -0.013, 0.010; p = 0.79). Findings were consistent across sensitivity analyses.

CONCLUSIONS

Although many midlife cardiovascular risk factors and cardiac structure and function measures are associated with late-life cognitive decline, incident prolonged QT interval in midlife was not associated with late-life cognitive performance or cognitive decline.

Design and Rationale of the Cognitive Intervention to Improve Memory in Heart Failure Patients Study

BACKGROUND

Memory loss is an independent predictor of mortality among heart failure patients. Twenty-three percent to 50% of heart failure patients have comorbid memory loss, but few interventions are available to treat the memory loss. The aims of this 3-arm randomized controlled trial were to (1) evaluate efficacy of computerized cognitive training intervention using BrainHQ to improve primary outcomes of memory and serum brain-derived neurotrophic factor levels and secondary outcomes of working memory, instrumental activities of daily living, and health-related quality of life among heart failure patients; (2) evaluate incremental cost-effectiveness of BrainHQ; and (3) examine depressive symptoms and genomic moderators of BrainHQ effect.

METHODS

A sample of 264 heart failure patients within 4 equal-sized blocks (normal/low baseline cognitive function and gender) will be randomly assigned to (1) BrainHQ, (2) active control computer-based crossword puzzles, and (3) usual care control groups. BrainHQ is an 8-week, 40-hour program individualized to each patient's performance. Data collection will be completed at baseline and at 10 weeks and 4 and 8 months. Descriptive statistics, mixed model analyses, and cost-utility analysis using intent-to-treat approach will be computed.

CONCLUSIONS

This research will provide new knowledge about the efficacy of BrainHQ to improve memory and increase serum brain-derived neurotrophic factor levels in heart failure. If efficacious, the intervention will provide a new therapeutic approach that is easy to disseminate to treat a serious comorbid condition of heart failure.

Profiling the unique protective properties of intracranial arterial endothelial cells

Cardiovascular disorders, like atherosclerosis and hypertension, are increasingly known to be associated with vascular cognitive impairment (VCI). In particular, intracranial atherosclerosis is one of the main causes of VCI, although plaque development occurs later in time and is structurally different compared to atherosclerosis in extracranial arteries. Recent data suggest that endothelial cells (ECs) that line the intracranial arteries may exert anti-atherosclerotic effects due to yet unidentified pathways. To gain insights into underlying mechanisms, we isolated post-mortem endothelial cells from both the intracranial basilar artery (BA) and the extracranial common carotid artery (CCA) from the same individual (total of 15 individuals) with laser capture microdissection. RNA sequencing revealed a distinct molecular signature of the two endothelial cell populations of which the most prominent ones were validated by means of qPCR. Our data reveal for the first time that intracranial artery ECs exert an immune quiescent phenotype. Secondly, genes known to be involved in the response of ECs to damage (inflammation, differentiation, adhesion, proliferation, permeability and oxidative stress) are differentially expressed in intracranial ECs compared to extracranial ECs. Finally, Desmoplakin (DSP) and Hop Homeobox (HOPX), two genes expressed at a higher level in intracranial ECs, and Sodium Voltage-Gated Channel Beta Subunit 3 (SCN3B), a gene expressed at a lower level in intracranial ECs compared to extracranial ECs, were shown to be responsive to shear stress and/or hypoxia. With our data we present a set of intracranial-specific endothelial genes that may contribute to its protective phenotype, thereby supporting proper perfusion and consequently may preserve cognitive function. Deciphering the molecular regulation of the vascular bed in the brain may lead to the identification of novel potential intervention strategies to halt vascular associated disorders, such as atherosclerosis and vascular cognitive dysfunction.

Supraphysiologic-dose anabolic-androgenic steroid use: A risk factor for dementia?

Supraphysiologic-dose anabolic-androgenic steroid (AAS) use is associated with physiologic, cognitive, and brain abnormalities similar to those found in people at risk for developing Alzheimer's Disease and its related dementias (AD/ADRD), which are associated with high brain β-amyloid (Aβ) and hyperphosphorylated tau (tau-P) protein levels. Supraphysiologic-dose AAS induces androgen abnormalities and excess oxidative stress, which have been linked to increased and decreased expression or activity of proteins that synthesize and eliminate, respectively, Aβ and tau-P. Aβ and tau-P accumulation may begin soon after initiating supraphysiologic-dose AAS use, which typically occurs in the early 20s, and their accumulation may be accelerated by other psychoactive substance use, which is common among non-medical AAS users. Accordingly, the widespread use of supraphysiologic-dose AAS may increase the numbers of people who develop dementia. Early diagnosis and correction of sex-steroid level abnormalities and excess oxidative stress could attenuate risk for developing AD/ADRD in supraphysiologic-dose AAS users, in people with other substance use disorders, and in people with low sex-steroid levels or excess oxidative stress associated with aging.

Association between cognitive function and parameters of echocardiography and coronary artery angiography

We aimed to determine whether there is an association between cognition and the results of echocardiography and angiography, based on neuropsychological assessments.

METHODS

We assessed the cognition of 85 patients who had recently undergone coronary artery angiography. We calculated the Gensini score for the coronary artery disease index. We also performed echocardiography to find indices of cardiac functioning.

RESULTS

The lower left ventricular ejection fraction correlated with lower scores on visuospatial, executive function, processing speed/attention and verbal memory capacities (p ≤ 0.05). A higher Gensini score and left atrial size correlated with lower executive function and processing speed/attention (p ≤ 0.05). In the group of patients with an impaired cognitive state, higher Gensini scores correlated with decreased processing speed/attention (p = 0.01) and the e' index was associated with lower capacity of executive function (p = 0.05).

CONCLUSION

Decreased processing speed/attention and executive function may correlate with cardiac dysfunction and coronary artery disease. The Color Trail Test may be considered for simple screening for cognitive problems in elderly patients with coronary artery disease or diastolic dysfunction.

Vascular Cognitive Impairment Linked to Brain Endothelium Inflammation in Early Stages of Heart Failure in Mice

BACKGROUND

Although advanced heart failure (HF) is a clinically documented risk factor for vascular cognitive impairment, the occurrence and pathomechanisms of vascular cognitive impairment in early stages of HF are equivocal. Here, we characterize vascular cognitive impairment in the early stages of HF development and assess whether cerebral hypoperfusion or prothrombotic conditions are involved.

METHODS AND RESULTS

Tgαq*44 mice with slowly developing isolated HF triggered by cardiomyocyte-specific overexpression of G-αq*44 protein were studied before the end-stage HF, at the ages of 3, 6, and 10 months: before left ventricle dysfunction; at the stage of early left ventricle diastolic dysfunction (with preserved ejection fraction); and left ventricle diastolic/systolic dysfunction, respectively. In 6- to 10-month-old but not in 3-month-old Tgαq*44 mice, behavioral and cognitive impairment was identified with compromised blood-brain barrier permeability, most significantly in brain cortex, that was associated with myelin sheet loss and changes in astrocytes and microglia. Brain endothelial cells displayed increased E-selectin immunoreactivity, which was accompanied by increased amyloid-β1-42 accumulation in piriform cortex and increased cortical oxidative stress (8-OHdG immunoreactivity). Resting cerebral blood flow measured by magnetic resonance imaging in vivo was preserved, but ex vivo NO-dependent cortical arteriole flow regulation was impaired. Platelet hyperreactivity was present in 3- to 10-month-old Tgαq*44 mice, but it was not associated with increased platelet-dependent thrombogenicity.

CONCLUSIONS

We report for the first time that vascular cognitive impairment is already present in the early stage of HF development, even before left ventricle systolic dysfunction. The underlying pathomechanism, independent of brain hypoperfusion, involves preceding platelet hyperreactivity and brain endothelium inflammatory activation.

Cognitive decline in heart failure

Cognitive impairment (CI) is common in older adults with heart failure (HF). The prevalence of CI is higher among patients with HF than in those without. The spectrum of CI in HF is similar to that observed in the general population and may range from delirium to isolated memory or non-memory-related deficits to dementia. Both HF with reduced ejection fraction and HF with preserved ejection fraction have been associated with defects in different domains of cognition. Numerous risk factors have been shown to contribute to CI in HF. Additionally, various pathophysiological mechanisms related to HF can contribute to cognitive decline. These conditions are not routinely screened for in clinical practice settings with HF populations, and guidelines on optimal assessment strategies are lacking. Validated tools and criteria should be used to differentiate acute cognitive decline (delirium) from chronic cognitive decline such as mild cognitive impairment and dementia. CI in HF has been associated with higher rates of disability and impairment in self-care activities that may in turn increase healthcare cost, hospital readmission and mortality. Early detection of CI may improve clinical outcomes in older adults with HF. Appropriate HF management strategies may also help to reduce CI in patients with HF, and future research is needed to develop and test newer and more effective interventions to improve outcomes in patients with HF and CI.

Self-Care for the Prevention and Management of Cardiovascular Disease and Stroke: A Scientific Statement for Healthcare Professionals From the American Heart Association

Self-care is defined as a naturalistic decision-making process addressing both the prevention and management of chronic illness, with core elements of self-care maintenance, self-care monitoring, and self-care management. In this scientific statement, we describe the importance of self-care in the American Heart Association mission and vision of building healthier lives, free of cardiovascular diseases and stroke. The evidence supporting specific self-care behaviors such as diet and exercise, barriers to self-care, and the effectiveness of self-care in improving outcomes is reviewed, as is the evidence supporting various individual, family-based, and community-based approaches to improving self-care. Although there are many nuances to the relationships between self-care and outcomes, there is strong evidence that self-care is effective in achieving the goals of the treatment plan and cannot be ignored. As such, greater emphasis should be placed on self-care in evidence-based guidelines.

Expert Opinion-Cognitive Decline in Heart Failure: More Attention is Needed

Cognitive decline is a prevalent condition and independent prognostic marker of unfavourable outcomes in patients with heart failure. The highest prevalence, up to 80 %, is reported in patients hospitalised due to acute decompensation. Numerous factors contribute to cognitive dysfunction in heart failure patients, with hypertension, atrial fibrillation, stroke and impaired haemodynamics being the most relevant. Cerebral hypoperfusion, disruption of blood-brain barrier, oxidative damage and brain-derived cytokines are pathogenic links between heart failure and alteration of cognitive functioning. White matter hyperintensities, lacunar infarcts and generalised volume loss are common features revealed by neuroimaging. Typically affected cognitive domains are presented. Assessment of cognitive functioning, even by simple screening tests, should be part of routine clinical examination of heart failure patients.

Nurse-Enhanced Computerized Cognitive Training Increases Serum Brain-Derived Neurotropic Factor Levels and Improves Working Memory in Heart Failure

BACKGROUND

Memory loss is common in heart failure (HF) patients, but few interventions have been tested to treat it. The objective of this study was to evaluate efficacy of a cognitive training intervention, Brain Fitness, to improve memory, serum brain-derived neurotropic factor (BDNF) levels, working memory, processing speed, executive function, instrumental activities of daily living, mobility, depressive symptoms, and health-related quality of life.

METHODS AND RESULTS

Twenty-seven HF patients were randomly assigned to Brain Fitness and health education active control interventions. Data were collected at baseline and 8 and 12 weeks. Linear mixed models analyses were completed. Patients in the Brain Fitness group were older with lower ejection fraction. At 12 weeks, a group by time interaction effect was found for serum BDNF levels (P = .011): serum BDNF levels increased among patients who completed Brain Fitness and decreased among patients who completed health education. No differences were found in memory, but a group by time interaction (P = .046) effect was found for working memory.

CONCLUSIONS

Findings support efficacy of Brain Fitness in improving working memory and serum BDNF levels as a biomarker of intervention response. A randomized controlled study is needed among a larger more diverse group of HF patients.

Mouse models to study the effect of cardiovascular risk factors on brain structure and cognition

Recent clinical data indicates that hemodynamic changes caused by cardiovascular diseases such as atherosclerosis, heart failure, and hypertension affect cognition. Yet, the underlying mechanisms of the resulting vascular cognitive impairment (VCI) are poorly understood. One reason for the lack of mechanistic insights in VCI is that research in dementia primarily focused on Alzheimer's disease models. To fill in this gap, we critically reviewed the published data and various models of VCI. Typical findings in VCI include reduced cerebral perfusion, blood-brain barrier alterations, white matter lesions, and cognitive deficits, which have also been reported in different cardiovascular mouse models. However, the tests performed are incomplete and differ between models, hampering a direct comparison between models and studies. Nevertheless, from the currently available data we conclude that a few existing surgical animal models show the key features of vascular cognitive decline, with the bilateral common carotid artery stenosis hypoperfusion mouse model as the most promising model. The transverse aortic constriction and myocardial infarction models may be good alternatives, but these models are as yet less characterized regarding the possible cerebral changes. Mixed models could be used to study the combined effects of different cardiovascular diseases on the deterioration of cognition during aging.

Left atrial size is independently associated with cognitive function

Left atrial (LA) diameter is easily attainable from echocardiograph and sensitive to underlying cardiovascular disease severity, although its association with neurocognitive outcomes is not well understood. Fifty older adults (64.50 ± 9.41 years), recruited from outpatient cardiology clinics and local papers who underwent magnetic resonance imaging, were administered the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), and completed psychosocial self-report measures. LA diameter was quantified using echocardiogram. Hierarchical regression analyses revealed that greater LA size was independently associated with reduced performance on the following RBANS composites: language, delayed memory, and total index (p < 0.05 for all). Hierarchical regression analysis demonstrated no significant association between LA diameter and whole brain volume (p > 0.05). The current study suggests that greater LA size is associated with cognitive dysfunction in older adults and prospective studies are needed to validate these findings and elucidate underlying mechanisms.

Cognitive performance in older adults with stable heart failure: longitudinal evidence for stability and improvement

Cognitive impairment is prevalent in heart failure (HF), though substantial variability in the pattern of cognitive impairment is found across studies. To clarify the nature of cognitive impairment in HF, we examined longitudinal trajectories across multiple domains of cognition in HF patients using latent growth class modeling. 115 HF patients completed a neuropsychological battery at baseline, 3-months and 12-months. Participants also completed the Beck Depression Inventory-II (BDI-II). Latent class growth analyses revealed a three-class model for attention/executive function, four-class model for memory, and a three-class model for language. The slope for attention/executive function and language remained stable, while improvements were noted in memory performance. Education and BDI-II significantly predicted the intercept for attention/executive function and language abilities. The BDI-II also predicted baseline memory. The current findings suggest that multiple performance-based classes of neuropsychological test performance exist within cognitive domains, though case-controlled prospective studies with extended follow-ups are needed to fully elucidate changes and predictors of cognitive function in HF.

Phenotypic profiling of cognitive impairment risk among patients with heart failure: a literature review of the usefulness of cardiac-related variables

BACKGROUND

Mild cognitive impairment among patients with heart failure can be subtle. Heart failure-related variables such as ejection fraction, low systolic blood pressure and functional status are reportedly associated with cognitive impairment among heart failure patients. The purpose of this literature review was to examine the value of cardiac variables commonly assessed during heart failure-related hospitalizations for a phenotypic profile of the risk of cognitive impairment.

METHOD

A literature review of primary research studies was conducted. Electronic databases (PubMed and CINAHL) were searched using the keywords heart failure, blood pressure, ejection fraction, functional status, and B-type natriuretic peptide (BNP) in combination with the terms cognition, cognitive function, cognitive dysfunction, and cognitive impairment.

RESULTS

Thirty-seven studies met the inclusion criteria. Evidence supports the potential utility of lower ejection fraction, lower blood pressure and functional status and elevated B-type natriuretic peptide as a phenotypic profile for an increased risk of cognitive impairment.

IMPLICATIONS

If the risk for cognitive impairment is suspected, specific evaluations of cognition can be performed. For community-dwelling heart failure patients with mild cognitive impairment, more intense interventions to support self-care, increased family involvement and more frequent follow up may be necessary.

Cardiovascular risk factors promote brain hypoperfusion leading to cognitive decline and dementia

Heart disease is the major leading cause of death and disability in the world. Mainly affecting the elderly population, heart disease and its main outcome, cardiovascular disease, have become an important risk factor in the development of cognitive decline and Alzheimer's disease (AD). This paper examines the evidence linking chronic brain hypoperfusion induced by a variety of cardiovascular deficits in the development of cognitive impairment preceding AD. The evidence indicates a strong association between AD and cardiovascular risk factors, including ApoE(4), atrial fibrillation, thrombotic events, hypertension, hypotension, heart failure, high serum markers of inflammation, coronary artery disease, low cardiac index, and valvular pathology. In elderly people whose cerebral perfusion is already diminished by their advanced age, additional reduction of cerebral blood flow stemming from abnormalities in the heart-brain vascular loop ostensibly increases the probability of developing AD. Evidence also suggests that a neuronal energy crisis brought on by relentless brain hypoperfusion may be responsible for protein synthesis abnormalities that later result in the classic neurodegenerative lesions involving the formation of amyloid-beta plaques and neurofibrillary tangles. Insight into how cardiovascular risk factors can induce progressive cognitive impairment offers an enhanced understanding of the multifactorial pathophysiology characterizing AD and ways at preventing or managing the cardiovascular precursors of this dementia.