Methods to Utilize Pulse Wave Velocity to Measure Alterations in Cerebral and Cardiovascular Parameters.

Alzheimer's Disease (AD) is a global health issue, affecting over 6 million in the United States, with that number expected to increase as the aging population grows. As a neurodegenerative disorder that affects memory and cognitive functions, it is well established that AD is associated with cardiovascular risk factors beyond only cerebral decline. However, the study of cerebrovascular techniques for AD is still evolving. Here, we provide reproducible methods to measure impedance-based pulse wave velocity (PWV), a marker of arterial stiffness, in the systemic vascular (aortic PWV) and in the cerebral vascular (cerebral PWV) systems. Using aortic impedance and this relatively novel technique of cerebral impedance to comprehensively describe the systemic vascular and the cerebral vascular systems, we examined the sex-dependent differences in 5x transgenic mice (5XFAD) with AD under normal and high-fat diet, and in wild-type mice under a normal diet. Additionally, we validated our method for measuring cerebrovascular impedance in a model of induced stress in 5XFAD. Together, our results show that sex and diet differences in wildtype and 5XFAD mice account for very minimal differences in cerebral impedance. Interestingly, 5XFAD, and not wildtype, male mice on a chow diet show higher cerebral impedance, suggesting pathological differences. Opposingly, when we subjected 5XFAD mice to stress, we found that females showed elevated cerebral impedance. Using this validated method of measuring impedance-based aortic and cerebral PWV, future research may explore the effects of modifying factors including age, chronic diet, and acute stress, which may mediate cardiovascular risk in AD. New and Noteworthy: Here, we presented a new technique which is an application of the concept of aortic impedance to determining cerebral impedance. While aortic PWV is typically utilized to study aortic stiffness, we also developed a technique of cerebral PWV to study cerebral vascular stiffness. This method may be useful in improving the rigor of studies that seek to have a dual focus on cardiovascular and cerebral function.

Association of low diastolic blood pressure with cardiovascular outcomes and all-cause mortality: A meta-analysis.

BACKGROUND: Reduction of diastolic blood pressure (DBP) below 70 mmHg may decrease perfusion to the heart and worsen cardiovascular (CV) outcomes. AIMS: Explore the association between low DBP and CV outcomes. METHODS: We searched the online databases until August 2023 for studies reporting the risk of all-cause mortality (ACM) or CV outcomes in patients with low versus normal DBP (70-80mm Hg). RESULTS: Inclusion of 10 studies (n = 1,998,223 patients) found that a mean achieved DBP < 60 mmHg was associated with an increased risk of all-cause mortality (HR 1.48; 95 % CI [1.26-1.74]), especially in patients with pre-existing CV disease. It was also associated to a higher risk of major adverse cardiovascular events (HR 1.84; [1.28-2.65]) and myocardial infarction (HR 1.49; [1.13-1.97]). A DBP of 60-69 mmHg was associated with an increased risk of all-cause mortality (HR 1.11; [1.03-1.20]). CONCLUSION: Reduction of DBP, particularly below 60 mmHg, is associated with increased risk of ACM.

Age-Related Differences in the Contribution of Systolic Blood Pressure and Biomarkers to Cardiovascular Disease Risk Prediction: The Atherosclerosis Risk in Communities (ARIC) Study.

We sought to determine how biomarkers known to be associated with hypertension-induced end-organ injury complement the use of systolic blood pressure (SBP) for cardiovascular disease (CVD) risk prediction at different ages. Using data from visits 2 (1990 to 1992) and 5 (2011 to 2013) of the Atherosclerosis Risk in Communities (ARIC) study, 3 models were used to predict CVD (composite of coronary heart disease, stroke, and heart failure). Model A included traditional risk factors (TRFs) except SBP, model B-TRF plus SBP, and model C-TRF plus biomarkers (high-sensitivity troponin T [hsTnT] and N-terminal pro-B-type natriuretic peptide [NT-proBNP]). Harrel's C-statistics were used to assess risk discrimination for CVD comparing models B and A and C and B. At visit 2, the addition of SBP to TRF (model B vs model A) significantly improved the C-statistic (∆C-statistic, 95% confidence interval 0.010, 0.007 to 0.013) whereas the addition of hsTnT to TRF (model C vs model B) decreased the C-statistic (∆C-statistic -0.0038, -0.0075 to -0.0001) compared with SBP. At visit 5, the addition of SBP to TRF did not significantly improve the C-statistic (∆C-statistic 0.001, -0.002 to 0.005) whereas the addition of both hsTnT and NT-proBNP to TRF significantly improved the C-statistic compared with SBP (∆C-statistic 0.028, 0.015 to 0.041 and 0.055, 0.036 to 0.074, respectively). In summary, the incremental value of SBP for CVD risk prediction diminishes with age whereas the incremental value of hsTnT and NT-proBNP increases with age.

Impact of Geroscience on Therapeutic Strategies for Older Adults With Cardiovascular Disease: JACC Scientific Statement.

Geroscience posits that cardiovascular disease (CVD) and other chronic diseases result from progressive erosion of the effectiveness of homeostatic mechanisms that oppose age-related accumulation of molecular damage. This hypothetical common root to chronic diseases explains why patients with CVD are often affected by multimorbidity and frailty and why older age negatively affects CVD prognosis and treatment response. Gerotherapeutics enhance resilience mechanisms that counter age-related molecular damage to prevent chronic diseases, frailty, and disability, thereby extending healthspan. Here, we describe the main resilience mechanisms of mammalian aging, with a focus on how they can affect CVD pathophysiology. We next present novel gerotherapeutic approaches, some of which are already used in management of CVD, and explore their potential to transform care and management of CVD. The geroscience paradigm is gaining traction broadly in medical specialties, with potential to mitigate premature aging, reduce health care disparities, and improve population healthspan.

Cardiovascular hemodynamics in mice with tumor necrosis factor receptor-associated factor 2 mediated cytoprotection in the heart.

Introduction: Many studies in mice have demonstrated that cardiac-specific innate immune signaling pathways can be reprogrammed to modulate inflammation in response to myocardial injury and improve outcomes. While the echocardiography standard parameters of left ventricular (LV) ejection fraction, fractional shortening, end-diastolic diameter, and others are used to assess cardiac function, their dependency on loading conditions somewhat limits their utility in completely reflecting the contractile function and global cardiovascular efficiency of the heart. A true measure of global cardiovascular efficiency should include the interaction between the ventricle and the aorta (ventricular-vascular coupling, VVC) as well as measures of aortic impedance and pulse wave velocity. Methods: We measured cardiac Doppler velocities, blood pressures, along with VVC, aortic impedance, and pulse wave velocity to evaluate global cardiac function in a mouse model of cardiac-restricted low levels of TRAF2 overexpression that conferred cytoprotection in the heart. Results: While previous studies reported that response to myocardial infarction and reperfusion was improved in the TRAF2 overexpressed mice, we found that TRAF2 mice had significantly lower cardiac systolic velocities and accelerations, diastolic atrial velocity, aortic pressures, rate-pressure product, LV contractility and relaxation, and stroke work when compared to littermate control mice. Also, we found significantly longer aortic ejection time, isovolumic contraction and relaxation times, and significantly higher mitral early/atrial ratio, myocardial performance index, and ventricular vascular coupling in the TRAF2 overexpression mice compared to their littermate controls. We found no significant differences in the aortic impedance and pulse wave velocity. Discussion: While the reported tolerance to ischemic insults in TRAF2 overexpression mice may suggest enhanced cardiac reserve, our results indicate diminished cardiac function in these mice.

Supplementing Glycine and N-Acetylcysteine (GlyNAC) in Older Adults Improves Glutathione Deficiency, Oxidative Stress, Mitochondrial Dysfunction, Inflammation, Physical Function, and Aging Hallmarks: A Randomized Clinical Trial.

BACKGROUND: Elevated oxidative stress (OxS), mitochondrial dysfunction, and hallmarks of aging are identified as key contributors to aging, but improving/reversing these defects in older adults (OA) is challenging. In prior studies, we identified that deficiency of the intracellular antioxidant glutathione (GSH) could play a role and reported that supplementing GlyNAC (combination of glycine and N-acetylcysteine [NAC]) in aged mice improved GSH deficiency, OxS, mitochondrial fatty-acid oxidation (MFO), and insulin resistance (IR). To test whether GlyNAC supplementation in OA could improve GSH deficiency, OxS, mitochondrial dysfunction, IR, physical function, and aging hallmarks, we conducted a placebo-controlled randomized clinical trial. METHODS: Twenty-four OA and 12 young adults (YA) were studied. OA was randomized to receive either GlyNAC (N = 12) or isonitrogenous alanine placebo (N = 12) for 16-weeks; YA (N = 12) received GlyNAC for 2-weeks. Participants were studied before, after 2-weeks, and after 16-weeks of supplementation to assess GSH concentrations, OxS, MFO, molecular regulators of energy metabolism, inflammation, endothelial function, IR, aging hallmarks, gait speed, muscle strength, 6-minute walk test, body composition, and blood pressure. RESULTS: Compared to YA, OA had GSH deficiency, OxS, mitochondrial dysfunction (with defective molecular regulation), inflammation, endothelial dysfunction, IR, multiple aging hallmarks, impaired physical function, increased waist circumference, and systolic blood pressure. GlyNAC (and not placebo) supplementation in OA improved/corrected these defects. CONCLUSION: GlyNAC supplementation in OA for 16-weeks was safe and well-tolerated. By combining the benefits of glycine, NAC and GSH, GlyNAC is an effective nutritional supplement that improves and reverses multiple age-associated abnormalities to promote health in aging humans. Clinical Trials Registration Number: NCT01870193.

Sex-specific phenotypes in the aging mouse heart and consequences for chronic fibrosis.

The incidence of diastolic dysfunction increases with age in both humans and mice. This is characterized by increased passive stiffness and slower relaxation of the left ventricle. The stiffness arises at least partially from progressively increased interstitial collagen deposition because of highly secretory fibroblasts. In the past, we demonstrated that AMPK activation via the drug 5-aminoimidazole-4-carboxamide riboside (AICAR) in middle-aged mice reduced adverse remodeling after myocardial infarction. Therefore, as an attempt to normalize the fibroblast phenotype, we used 21-mo-old male and female mice and treated them with AICAR (0.166 mg/g body wt) where each mouse was followed in a functional study over a 3-mo period. We found sex-related differences in extracellular matrix (ECM) composition as well as heart function indices at baseline, which were further accentuated by AICAR treatment. AICAR attenuated the age-related increase in left atrial volume (LAV, an indicator of diastolic dysfunction) in female but not in male hearts, which was associated with reduced collagen deposition in the old female heart, and reduced the transcription factor Gli1 expression in cardiac fibroblasts. We further demonstrated that collagen synthesis was dependent on Gli1, which is a target of AMPK-mediated degradation. By contrast, AICAR had a minor impact on cardiac fibroblasts in the old male heart because of blunted AMPK phosphorylation. Hence, it did not significantly improve old male heart function indices. In conclusion, we demonstrated that male and female hearts are phenotypically different, and sex-specific differences need to be considered when analyzing the response to pharmacological intervention.NEW & NOTEWORTHY The aging heart develops diastolic dysfunction because of increased collagen deposition. We attempted to reduce collagen expression in the old heart by activating AMPK using AICAR. An improvement of diastolic function and reduction of cardiac fibrosis was found only in the female heart and correlated with decreased procollagen expression and increased degradation of the transcription factor Gli1. Male hearts display blunted AICAR-dependent AMPK activation and therefore this treatment had no benefits for the male mice.

Exercise Intolerance in Older Adults With Heart Failure With Preserved Ejection Fraction: JACC State-of-the-Art Review.

Exercise intolerance (EI) is the primary manifestation of chronic heart failure with preserved ejection fraction (HFpEF), the most common form of heart failure among older individuals. The recent recognition that HFpEF is likely a systemic, multiorgan disorder that shares characteristics with other common, difficult-to-treat, aging-related disorders suggests that novel insights may be gained from combining knowledge and concepts from aging and cardiovascular disease disciplines. This state-of-the-art review is based on the outcomes of a National Institute of Aging-sponsored working group meeting on aging and EI in HFpEF. We discuss aging-related and extracardiac contributors to EI in HFpEF and provide the rationale for a transdisciplinary, "gero-centric" approach to advance our understanding of EI in HFpEF and identify promising new therapeutic targets. We also provide a framework for prioritizing future research, including developing a uniform, comprehensive approach to phenotypic characterization of HFpEF, elucidating key geroscience targets for treatment, and conducting proof-of-concept trials to modify these targets.

Decade-Long Nationwide Trends and Disparities in Use of Comfort Care Interventions for Patients With Ischemic Stroke.

Background Stroke remains one of the leading causes of disability and death in the United States. We characterized 10-year nationwide trends in use of comfort care interventions (CCIs) among patients with ischemic stroke, particularly pertaining to acute thrombolytic therapy with intravenous tissue-type plasminogen activator and endovascular thrombectomy, and describe in-hospital outcomes and costs. Methods and Results We analyzed the National Inpatient Sample from 2006 to 2015 and identified adult patients with ischemic stroke with or without thrombolytic therapy and CCIs using validated International Classification of Diseases, Ninth Revision (ICD-9) codes. We report adjusted odds ratios (ORs) and 95% CI of CCI usage across five 2-year periods. Of 4 249 201 ischemic stroke encounters, 3.8% had CCI use. CCI use increased over time (adjusted OR, 4.80; 95% CI, 4.15-5.55) regardless of acute treatment type. Advanced age, female sex, White race, non-Medicare insurance, higher income, disease severity, comorbidity burden, and discharge from non-northeastern teaching hospitals were independently associated with receiving CCIs. In the fully adjusted model, thrombolytic therapy and endovascular thrombectomy, respectively, conferred a 6% and 10% greater likelihood of receiving CCIs. Among CCI users, there was a significant decline in in-hospital mortality compared with all other dispositions over time (adjusted OR, 0.46; 95% CI, 0.38-0.56). Despite longer length of stay, CCI hospitalizations incurred 16% lower adjusted costs. Conclusions CCI use among patients with ischemic stroke has increased regardless of acute treatment type. Nonetheless, considerable disparities persist. Closing the disparities gap and optimizing access, outcomes, and costs for CCIs among patients with stroke are important avenues for further research.

NLRP3 inflammasome is a key driver of obesity-induced atrial arrhythmias.

AIMS: Obesity, an established risk factor of atrial fibrillation (AF), is frequently associated with enhanced inflammatory response. However, whether inflammatory signaling is causally linked to AF pathogenesis in obesity remains elusive. We recently demonstrated that the constitutive activation of the 'NACHT, LRR, and PYD Domains-containing Protein 3' (NLRP3) inflammasome promotes AF susceptibility. In this study, we hypothesized that the NLRP3 inflammasome is a key driver of obesity-induced AF. METHODS AND RESULTS: Western blotting was performed to determine the level of NLRP3 inflammasome activation in atrial tissues of obese patients, sheep, and diet-induced obese (DIO) mice. The increased body weight in patients, sheep, and mice was associated with enhanced NLRP3-inflammasome activation. To determine whether NLRP3 contributes to the obesity-induced atrial arrhythmogenesis, wild-type (WT) and NLRP3 homozygous knockout (NLRP3-/-) mice were subjected to high-fat-diet (HFD) or normal chow (NC) for 10 weeks. Relative to NC-fed WT mice, HFD-fed WT mice were more susceptible to pacing-induced AF with longer AF duration. In contrast, HFD-fed NLRP3-/- mice were resistant to pacing-induced AF. Optical mapping in DIO mice revealed an arrhythmogenic substrate characterized by abbreviated refractoriness and action potential duration (APD), two key determinants of reentry-promoting electrical remodeling. Upregulation of ultra-rapid delayed-rectifier K+-channel (Kv1.5) contributed to the shortening of atrial refractoriness. Increased profibrotic signaling and fibrosis along with abnormal Ca2+ release from sarcoplasmic reticulum (SR) accompanied atrial arrhythmogenesis in DIO mice. Conversely, genetic ablation of Nlrp3 (NLRP3-/-) in HFD-fed mice prevented the increases in Kv1.5 and the evolution of electrical remodeling, the upregulation of profibrotic genes, and abnormal SR Ca2+ release in DIO mice. CONCLUSION: These results demonstrate that the atrial NLRP3 inflammasome is a key driver of obesity-induced atrial arrhythmogenesis and establishes a mechanistic link between obesity-induced AF and NLRP3-inflammasome activation.

Aortic acceleration as a noninvasive index of left ventricular contractility in the mouse.

The maximum value of the first derivative of the invasively measured left ventricular (LV) pressure (+ dP/dtmax or P') is often used to quantify LV contractility, which in mice is limited to a single terminal study. Thus, determination of P' in mouse longitudinal/serial studies requires a group of mice at each desired time point resulting in "pseudo" serial measurements. Alternatively, a noninvasive surrogate for P' will allow for repeated measurements on the same group of mice, thereby minimizing physiological variability and requiring fewer animals. In this study we evaluated aortic acceleration and other parameters of aortic flow velocity as noninvasive indices of LV contractility in mice. We simultaneously measured LV pressure invasively with an intravascular pressure catheter and aortic flow velocity noninvasively with a pulsed Doppler probe in mice, at baseline and after the administration of the positive inotrope, dobutamine. Regression analysis of P' versus peak aortic velocity (vp), peak velocity squared/rise time (vp2/T), peak (+ dvp/dt or v'p) and mean (+ dvm/dt or v'm) aortic acceleration showed a high degree of association (P' versus: vp, r2 = 0.77; vp2/T, r2 = 0.86; v'p, r2 = 0.80; and v'm, r2 = 0.89). The results suggest that mean or peak aortic acceleration or the other parameters may be used as a noninvasive index of LV contractility.

Implementing Health Care Quality Measures in Electronic Health Records: A Conceptual Model.

BACKGROUND/OBJECTIVES: There is significant literature on the development and validation of quality measures, but comparably less on their implementation into learning health systems. Electronic Health Records (EHRs) have made vast amounts of data available for quality improvement purposes. In this paper we describe a conceptual model for EHR implementation of quality measures. DESIGN: The model involves five steps: (1) select a measure; (2) define measure criteria; (3) validate criteria and measurement process; (4) improve recording of measure-related activity; and (5) engage quality improvement processes. The model was used to develop and implement a quality measure in the Home-Based Medical Care (HBMC) setting. SETTING: Harris Health House Call Program (HHHC) provides primary medical and palliative care for homebound patients in Houston. PARTICIPANTS: Four-hundred twenty-four primary care patients followed in the HHHC. MEASUREMENT: Completion rate of the 9-item Patient Health Questionnaire (PHQ-9) within the Electronic Health Record of newly enrolled HHHC patients. RESULTS: Use of the conceptual model to guide implementation of a quality measure of depression screening in a HMBC practice was successful. Additional components of early leadership and clinician buy-in were required, as well as strong relationships with IT to ease implementation and limit disruptions in clinicians' work-flow. CONCLUSION: This conceptual model was feasible for guiding implementation of a quality measure for depression care of HBMC patients, and it can guide broader implementation of EHR-based quality measures in the future.

Treatment with a DC-SIGN ligand reduces macrophage polarization and diastolic dysfunction in the aging female but not male mouse hearts.

Cardiac diastolic dysfunction in aging arises from increased ventricular stiffness caused by inflammation and interstitial fibrosis. The diastolic dysfunction contributes to heart failure with preserved ejection fraction (HFpEF), which in the aging population is more common in women. This report examines its progression over 12 weeks in aging C57BL/6J mice and correlates its development with changes in macrophage polarization and collagen deposition.Aged C57BL/6J mice were injected with dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN) ligand 1 (DCSL1, an anti-inflammatory agent) or saline for 12 weeks. Echo and Doppler measurements were performed before and after 4 and 12 weeks of treatment. DCSL1 prevented the worsening of diastolic dysfunction over time in females but not in males. Cardiac single cell suspensions analyzed by flow cytometry revealed changes in the inflammatory infiltrate: (1) in males, there was an increased total number of leukocytes with an increased pro-inflammatory profile compared with females and they did not respond to DCSL1; (2) by contrast, DCSL1 treatment resulted in a shift in macrophage polarization to an anti-inflammatory phenotype in females. Notably, DCSL1 preferentially targeted tumor necrosis factor-α (TNFα+) pro-inflammatory macrophages. The reduction in pro-inflammatory macrophage polarization was accompanied by a decrease in collagen content in the heart.Age-associated diastolic dysfunction in mice is more severe in females and is associated with unique changes in macrophage polarization in cardiac tissue. Treatment with DCSL1 mitigates the changes in inflammation, cardiac function, and fibrosis. The characteristics of diastolic dysfunction in aging female mice mimic similar changes in aging women.

Plasma Dehydroepiandrosterone Sulfate and Cardiovascular Disease Risk in Older Men and Women.

CONTEXT: Lower dehydroepiandrosterone-sulfate (DHEA-S) levels have been inconsistently associated with coronary heart disease (CHD) and mortality. Data are limited for heart failure (HF) and association between DHEA-S change and events. OBJECTIVE: Assess associations between low DHEA-S/DHEA-S change and incident HF hospitalization, CHD, and mortality in older adults. DESIGN: DHEA-S was measured in stored plasma from visits 4 (1996-1998) and 5 (2011-2013) of the Atherosclerosis Risk in Communities study. Follow-up for incident events: 18 years for DHEA-S level; 5.5 years for DHEA-S change. SETTING: General community. PARTICIPANTS: Individuals without prevalent cardiovascular disease (n = 8143, mean age 63 years). MAIN OUTCOME MEASURE: Associations between DHEA-S and incident HF hospitalization, CHD, or mortality; associations between 15-year change in DHEA-S (n = 3706) and cardiovascular events. RESULTS: DHEA-S below the 15th sex-specific percentile of the study population (men: 55.4 µg/dL; women: 27.4 µg/dL) was associated with increased HF hospitalization (men: hazard ratio [HR] 1.30, 95% confidence interval [CI], 1.07-1.58; women: HR 1.42, 95% CI, 1.13-1.79); DHEA-S below the 25th sex-specific percentile (men: 70.0 µg/dL; women: 37.1 µg/dL) was associated with increased death (men: HR 1.12, 95% CI, 1.01-1.25; women: HR 1.19, 95% CI, 1.03-1.37). In men, but not women, greater percentage decrease in DHEA-S was associated with increased HF hospitalization (HR 1.94, 95% CI, 1.11-3.39). Low DHEA-S and change in DHEA-S were not associated with incident CHD. CONCLUSIONS: Low DHEA-S is associated with increased risk for HF and mortality but not CHD. Further investigation is warranted to evaluate mechanisms underlying these associations.

Decreasing Heart Failure Readmissions Among Older Patients With Cognitive Impairment by Engaging Caregivers.

BACKGROUND: Cognitive impairment is common in older patients with heart failure (HF), leading to higher 30-day readmission rates than those without cognitive impairment. OBJECTIVES: The aim of this study was to determine whether increased readmissions in older adults with cognitive impairment are related to HF severity and whether readmissions can be modified by caregiver inclusion in nursing discharge education. METHODS: This study used prospective quality improvement program of cognitive testing and inclusion of caregivers in discharge education with chart review. Two hundred thirty-two patients older than 70 years admitted with HF were screened for cognitive impairment using the Mini-Cog; if score was less than 4, nurses were asked to include caregivers in education on 2 cardiovascular units with an enhanced discharge program. Individuals with ventricular assist device, transplant, or hospice were excluded. Measurements include Mini-Cog score, 30-day readmissions, readmission risk score, ejection fraction, brain natriuretic peptide, and medical comorbidities. RESULTS: Readmission Risk Scores for HF did not correlate with Mini-Cog scores, but admission brain natriuretic peptide levels were less abnormal in those with better Mini-Cog scores. Only for patients with cognitive impairment, involving caregivers in discharge teaching given by registered and advanced practice nurses was associated with decreased 30-day readmissions from 35% to 16% (P = .01). Readmission rates without/with cognitive impairment were 14.1% and 23.8%, respectively (P = .09). Abnormal Mini-Cog screen was associated with a significantly increased risk of 30-day readmission (odds ratio, 2.23; 95% confidence interval, 1.06-4.68; P = .03), whereas nurse documentation of education with family was associated with a significantly decreased risk of 30-day readmission (odds ratio, 0.46; 95% confidence interval, 0.24-0.90; P = .02). CONCLUSIONS: Involving caregivers in discharge education significantly reduced 30-day readmission rates for patients with HF and cognitive impairment. The Readmission Risk Score was similar between patients older than 70 years with and without cognitive impairment. We have hypothesis-generating evidence that identification of cognitive impairment and targeted caregiver engagement by nurses may be critical in the reduction of readmission rates for older patients with HF.