1
|
Aghilinejad A, Amlani F, Mazandarani SP, King KS, Pahlevan NM. Mechanistic insights on age-related changes in heart-aorta-brain hemodynamic coupling using a pulse wave model of the entire circulatory system. Am J Physiol Heart Circ Physiol 2023; 325:H1193-H1209. [PMID: 37712923 PMCID: PMC10908406 DOI: 10.1152/ajpheart.00314.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 08/14/2023] [Accepted: 08/31/2023] [Indexed: 09/16/2023]
Abstract
Age-related changes in aortic biomechanics can impact the brain by reducing blood flow and increasing pulsatile energy transmission. Clinical studies have shown that impaired cardiac function in patients with heart failure is associated with cognitive impairment. Although previous studies have attempted to elucidate the complex relationship between age-associated aortic stiffening and pulsatility transmission to the cerebral network, they have not adequately addressed the effect of interactions between aortic stiffness and left ventricle (LV) contractility (neither on energy transmission nor on brain perfusion). In this study, we use a well-established and validated one-dimensional blood flow and pulse wave computational model of the circulatory system to address how age-related changes in cardiac function and vasculature affect the underlying mechanisms involved in the LV-aorta-brain hemodynamic coupling. Our results reveal how LV contractility affects pulsatile energy transmission to the brain, even with preserved cardiac output. Our model demonstrates the existence of an optimal heart rate (near the normal human heart rate) that minimizes pulsatile energy transmission to the brain at different contractility levels. Our findings further suggest that the reduction in cerebral blood flow at low levels of LV contractility is more prominent in the setting of age-related aortic stiffening. Maintaining optimal blood flow to the brain requires either an increase in contractility or an increase in heart rate. The former consistently leads to higher pulsatile power transmission, and the latter can either increase or decrease subsequent pulsatile power transmission to the brain.NEW & NOTEWORTHY We investigated the impact of major aging mechanisms of the arterial system and cardiac function on brain hemodynamics. Our findings suggest that aging has a significant impact on heart-aorta-brain coupling through changes in both arterial stiffening and left ventricle (LV) contractility. Understanding the underlying physical mechanisms involved here can potentially be a key step for developing more effective therapeutic strategies that can mitigate the contributions of abnormal LV-arterial coupling toward neurodegenerative diseases and dementia.
Collapse
Affiliation(s)
- Arian Aghilinejad
- Department of Aerospace and Mechanical Engineering, University of Southern California, Los Angeles, California, United States
| | - Faisal Amlani
- Laboratoire de Mécanique Paris-Saclay, Université Paris-Saclay, Paris, France
| | - Sohrab P Mazandarani
- Department of Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California, United States
| | - Kevin S King
- Barrow Neurological Institute, Phoenix, Arizona, United States
| | - Niema M Pahlevan
- Department of Aerospace and Mechanical Engineering, University of Southern California, Los Angeles, California, United States
- Division of Cardiovascular Medicine, Department of Medicine, University of Southern California, Los Angeles, California, United States
| |
Collapse
|
2
|
Xu X, Xu H, Zhang Z. Cerebral amyloid angiopathy-related cardiac injury: Focus on cardiac cell death. Front Cell Dev Biol 2023; 11:1156970. [PMID: 36910141 PMCID: PMC9998697 DOI: 10.3389/fcell.2023.1156970] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 02/16/2023] [Indexed: 03/14/2023] Open
Abstract
Cerebral amyloid angiopathy (CAA) is a kind of disease in which amyloid β (Aβ) and other amyloid protein deposits in the cerebral cortex and the small blood vessels of the brain, causing cerebrovascular and brain parenchymal damage. CAA patients are often accompanied by cardiac injury, involving Aβ, tau and transthyroxine amyloid (ATTR). Aβ is the main injury factor of CAA, which can accelerate the formation of coronary artery atherosclerosis, aortic valve osteogenesis calcification and cardiomyocytes basophilic degeneration. In the early stage of CAA (pre-stroke), the accompanying locus coeruleus (LC) amyloidosis, vasculitis and circulating Aβ will induce first hit to the heart. When the CAA progresses to an advanced stage and causes a cerebral hemorrhage, the hemorrhage leads to autonomic nervous function disturbance, catecholamine surges, and systemic inflammation reaction, which can deal the second hit to the heart. Based on the brain-heart axis, CAA and its associated cardiac injury can create a vicious cycle that accelerates the progression of each other.
Collapse
Affiliation(s)
- Xiaofang Xu
- Department of Critical Care Medicine, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Huikang Xu
- Department of Critical Care Medicine, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Zhaocai Zhang
- Department of Critical Care Medicine, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Key Laboratory of the Diagnosis and Treatment for Severe Trauma and Burn of Zhejiang Province, Hangzhou, China.,Zhejiang Province Clinical Research Center for Emergency and Critical care medicine, Hangzhou, China
| |
Collapse
|
3
|
Duan C, Shi J, Yuan G, Shou X, Chen T, Zhu X, Yang Y, Hu Y. Causal Association Between Heart Failure and Alzheimer's Disease: A Two-Sample Bidirectional Mendelian Randomization Study. Front Genet 2022; 12:772343. [PMID: 35087565 PMCID: PMC8787319 DOI: 10.3389/fgene.2021.772343] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 11/18/2021] [Indexed: 11/13/2022] Open
Abstract
Background: Traditional observational studies have demonstrated an association between heart failure and Alzheimer's disease. The strengths of observational studies lie in their speed of implementation, cost, and applicability to rare diseases. However, observational studies have several limitations, such as uncontrollable confounders. Therefore, we employed Mendelian randomization of genetic variants to evaluate the causal relationships existing between AD and HF, which can avoid these limitations. Materials and Methods: A two-sample bidirectional MR analysis was employed. All datasets were results from the UK's Medical Research Council Integrative Epidemiology Unit genome-wide association study database, and we conducted a series of control steps to select the most suitable single-nucleotide polymorphisms for MR analysis, for which five primary methods are offered. We reversed the functions of exposure and outcomes to explore the causal direction of HF and AD. Sensitivity analysis was used to conduct several tests to avoid heterogeneity and pleiotropic bias in the MR results. Results: Our MR studies did not support a meaningful causal relationship between AD on HF (MR-Egger, p = 0.634 > 0.05; weighted median (WM), p = 0.337 > 0.05; inverse variance weighted (IVW), p = 0.471 > 0.05; simple mode, p = 0.454 > 0.05; weighted mode, p = 0.401 > 0.05). At the same time, we did not find a significant causal relationship between HF and AD with four of the methods (MR-Egger, p = 0.195 > 0.05; IVW, p = 0.0879 > 0.05; simple mode, p = 0.170 > 0.05; weighted mode, p = 0.110 > 0.05), but the WM method indicated a significant effect of HF on AD (p = 0.025 < 0.05). Because the statistical powers of IVW and MR-Egger are more than that of WM, we think that there is no causal effect of HF on AD. Sensitivity analysis and horizontal pleiotropy were not detected in the MR analysis. Conclusion: Our results did not provide significant evidence indicating any causal relationships between HF and AD in the European population. Therefore, more large-scale datasets or datasets related to similar factors are expected for further MR analysis.
Collapse
Affiliation(s)
- Chenglin Duan
- Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China.,Beijing University of Chinese Medicine, Beijing, China
| | - Jingjing Shi
- Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Guozhen Yuan
- Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Xintian Shou
- Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China.,Beijing University of Chinese Medicine, Beijing, China
| | - Ting Chen
- Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China.,Beijing University of Chinese Medicine, Beijing, China
| | - Xueping Zhu
- Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Yihan Yang
- Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China.,Beijing University of Chinese Medicine, Beijing, China
| | - Yuanhui Hu
- Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| |
Collapse
|
4
|
Nicholson G, Gandra SR, Halbert RJ, Richhariya A, Nordyke RJ. Patient-level costs of major cardiovascular conditions: a review of the international literature. CLINICOECONOMICS AND OUTCOMES RESEARCH 2016; 8:495-506. [PMID: 27703385 PMCID: PMC5036826 DOI: 10.2147/ceor.s89331] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Objective Robust cost estimates of cardiovascular (CV) events are required for assessing health care interventions aimed at reducing the economic burden of major adverse CV events. This review synthesizes international cost estimates of CV events. Methods MEDLINE database was searched electronically for English language studies published during 2007–2012, with cost estimates for CV events of interest – unstable angina, myocardial infarction, heart failure, stroke, and CV revascularization. Included studies provided at least one estimate of patient-level direct costs in adults for any identified country. Information on study characteristics and cost estimates were collected. All costs were adjusted for inflation to 2013 values. Results Across the 114 studies included, the average cost was US $6,466 for unstable angina, $11,664 for acute myocardial infarction, $11,686 for acute heart failure, $11,635 for acute ischemic stroke, $37,611 for coronary artery bypass graft, and $13,501 for percutaneous coronary intervention. The ranges for cost estimates varied widely across countries with US cost estimate being at least twice as high as European Union costs for some conditions. Few studies were found on populations outside the US and European Union. Conclusion This review showed wide variation in the cost of CV events within and across countries, while showcasing the continuing economic burden of CV disease. The variability in costs was primarily attributable to differences in study population, costing methodologies, and reporting differences. Reliable cost estimates for assessing economic value of interventions in CV disease are needed.
Collapse
|
5
|
Affiliation(s)
- A E Roher
- Banner Sun Health Research Institute, Sun City, AZ, USA
| |
Collapse
|
6
|
Abstract
It has recently been proposed that heart failure is a risk factor for Alzheimer's disease. Decreased cerebral blood flow and neurohormonal activation due to heart failure may contribute to the dysfunction of the neurovascular unit and cause an energy crisis in neurons. This leads to the impaired clearance of amyloid beta and hyperphosphorylation of tau protein, resulting in the formation of amyloid beta plaques and neurofibrillary tangles. In this article, we will summarize the current understanding of the relationship between heart failure and Alzheimer's disease based on epidemiological studies, brain imaging research, pathological findings and the use of animal models. The importance of atherosclerosis, myocardial infarction, atrial fibrillation, blood pressure and valve disease as well as the effect of relevant medications will be discussed.
Collapse
Affiliation(s)
- P Cermakova
- Division for Neurogeriatrics, Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Karolinska InstitutetHuddinge, Sweden
- International Clinical Research Center and St. Anne's University HospitalBrno, Czech Republic
| | - M Eriksdotter
- Department of Geriatric Medicine, Karolinska University HospitalStockholm, Sweden
- Division of Clinical Geriatrics, Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Karolinska InstitutetStockholm, Sweden
| | - L H Lund
- Department of Cardiology, Karolinska University HospitalStockholm, Sweden
- Unit of Cardiology, Department of Medicine, Karolinska InstitutetStockholm, Sweden
| | - B Winblad
- Division for Neurogeriatrics, Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Karolinska InstitutetHuddinge, Sweden
- Department of Geriatric Medicine, Karolinska University HospitalStockholm, Sweden
| | - P Religa
- Department of Medicine, Center for Molecular Medicine, Karolinska InstitutetStockholm, Sweden
| | - D Religa
- Division for Neurogeriatrics, Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Karolinska InstitutetHuddinge, Sweden
- Department of Geriatric Medicine, Karolinska University HospitalStockholm, Sweden
| |
Collapse
|
7
|
Fillit H, Cummings J, Neumann P, McLaughlin T, Salavtore P, Leibman C. Novel approaches to incorporating pharmacoeconomic studies into phase III clinical trials for Alzheimer's disease. J Nutr Health Aging 2010; 14:640-7. [PMID: 20922340 DOI: 10.1007/s12603-010-0310-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The societal and individual costs of Alzheimer's disease are significant, worldwide. As the world ages, these costs are increasing rapidly, while health systems face finite budgets. As a result, many regulators and payers will require or at least consider phase III cost-effectiveness data (in addition to safety and efficacy data) for drug approval and reimbursement, increasing the risks and costs of drug development. Incorporating pharmacoeconomic studies in phase III clinical trials for Alzheimer's disease presents a number of challenges. We propose several specific suggestions to improve the design of pharmacoeconomic studies in phase III clinical trials. We propose that acute episodes of care are key outcome measures for pharmacoeconomic studies. To improve the possibility of detecting a pharmacoeconomic impact in phase III, we suggest several strategies including; study designs for enrichment of pharmacoeconomic outcomes that include co-morbidity of patients; reducing variability of care that can affect pharmacoeconomic outcomes through standardized care management; employing administrative claims data to better capture meaningful pharmacoeconomic data; and extending clinical trials in open label follow-up periods in which pharmacoeconomic data are captured electronically by administrative claims. Specific aspects of power analysis for pharmacoeconomic studies are presented. The particular pharmacoeconomic challenges caused by the use of biomarkers in clinical trials, the increasing use of multinational studies, and the pharmacoeconomic challenges presented by biologicals in development for Alzheimer's disease are discussed. In summary, since we are entering an era in which pharmacoeconomic studies will be essential in drug development for supporting regulatory approval, payor reimbursement and integration of new therapies into clinical care, we must consider the design and incorporation of pharmacoeconomic studies in phase III clinical trials more seriously and more creatively.
Collapse
Affiliation(s)
- H Fillit
- The Alzheimer's Drug Discovery Foundation, NY, NY, USA
| | | | | | | | | | | |
Collapse
|