Arterial stiffness/elasticity in the contribution to progression of heart failure

Predictors of Length of Hospital Stay And In-Hospital Adverse Events in Patients With Acute Decompensated Heart Failure: In-hospital 24-Hour Blood Pressure Monitoring Data

BACKGROUND

Neurohumoral alterations in heart failure (HF) affect blood pressure variability (BPV) and vascular compliance, but little is known about this subject among patients admitted to hospital with decompensated HF. This study sought to investigate in-hospital 24-hour blood pressure monitoring (HBPM) derived BPV parameters and vascular compliance in patients with decompensated HF and to explore the association of these parameters with hospitalization length and in-hospital adverse events.

METHODS

A 24-hour blood pressure monitor was applied during the first 6 hours of admission to the hospital in patients with decompensated HF. Circadian patterns were determined by the study patients. Average real variability (ARV), pulse pressure index (PPI), pulse stiffening ratio (PSR), and ambulatory arterial stiffness index (AASI) values were calculated from HBPM recordings. Admission and discharge N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels, length of hospitalization, and in-hospital adverse events were recorded.

RESULTS

A total of 167 decompensated HF patients were included in the study. The dipper group exhibited a greater NT-proBNP decrease with the treatment compared to the non-dipper group and reverse dipper group. Hospitalization length was lower in the dipper group than in the non-dipper and reverse dipper groups. While ARV, AASI, and PSR were independently associated with the length of hospitalization, ARV, AASI, and PPI were independently associated with in-hospital adverse events.

CONCLUSIONS

Post-admission HBPM-derived parameters (dipper pattern, ARV, PPI, PSR, AASI) of patients admitted to hospital with decompensated HF provide important prognostic information and predict the length of hospital stay.

Comparison of arterial stiffness indices measured by pulse wave velocity and pulse wave analysis for predicting cardiovascular and all-cause mortality in a Chinese population

Arterial stiffness measured by pulse wave velocity and pulse wave analysis has been widely studied in different populations in terms of its correlation with cardiovascular events and all-cause mortality. It remains unknown which arterial stiffness index is better for risk stratification in the general population. We included 4129 participants from Gaoyou County, Jiangsu Province, China, with a median follow-up of 11 years. The primary endpoint was cardiovascular mortality, and the secondary endpoint was all-cause mortality. Harrell's C-index, net reclassification improvement (NRI) and integrated discrimination improvement (IDI) based on the Cox proportional hazards regression model were evaluated to assess predictive discrimination and accuracy. The associations between the 4 indices and cardiovascular mortality remained significant after adjusting for the Framingham Risk Score (FRS) and/or associated risk factors. Considering reclassification based on the newly integrated models (FRS model combined with the 4 indices), NRI for cardiovascular mortality showed that haPWV and baPWV had more significant improvement in reclassification compared with C1 and C2 [NRI with 95% CI: haPWV 0.410 (0.293, 0.523); baPWV 0.447 (0.330, 0.553); C1 0.312 (0.182, 0.454); C2 0.328 (0.159, 0.463); all P < 0.05]. This study showed that pulse wave velocity (haPWV and baPWV) provides better discrimination of long-term risk than arterial elasticity indices (C1 and C2) in the general population.

Increased arterial stiffness elevates the risk of heart failure in diabetic patients

BACKGROUND

Previous studies have shown that arterial stiffness (AS) was a risk factor for heart failure (HF) in nondiabetic patients. We aimed to analyze this impact in a community-based diabetic population.

METHODS

Our study excluded those who had HF before brachial-ankle pulse wave velocity (baPWV) measurement and included 9041 participants finally. Subjects were divided into the normal (<14 m/s), intermediate (14-18 m/s), and elevated baPWV groups (>18 m/s) based on baPWV values. Multivariate Cox proportional hazard model was used to analyze the effect of AS on HF risk.

RESULTS

During the median follow-up of 4.19 years, 213 patients had HF. The results of Cox model showed that HF risk in the elevated baPWV group was 2.25 times higher than that in the normal baPWV group (95% confidence interval [CI]: 1.24-4.11). HF risk increased by 18% (95% CI:1.03-1.35) for every 1 additional standard deviation(SD)of baPWV. Restricted cubic spline results showed statistically significant overall and non-linear associations between AS and HF risk (P < 0.05). The subgroup analysis and sensitivity analysis were consistent with that of total population.

CONCLUSIONS

AS is an independent risk factor for developing HF in the diabetic population, and AS exhibits a dose-response relationship with HF risk.

Differential Impact of IL-32 Isoforms on the Functions of Coronary Artery Endothelial Cells: A Potential Link with Arterial Stiffness and Atherosclerosis

Chronic inflammation is associated with higher risk of cardiovascular disease (CVD) in people living with HIV (PLWH). We have previously shown that interleukin-32 (IL-32), a multi-isoform proinflammatory cytokine, is chronically upregulated in PLWH and is linked with CVD. However, the mechanistic role of the different IL-32 isoforms in CVD are yet to be identified. In this study, we aimed to investigate the potential impact of IL-32 isoforms on coronary artery endothelial cells (CAEC), whose dysfunction represents a major factor for atherosclerosis. Our results demonstrated that the predominantly expressed IL-32 isoforms (IL-32β and IL-32γ) have a selective impact on the production of the proinflammatory cytokine IL-6 by CAEC. Furthermore, these two isoforms induced endothelial cell dysfunction by upregulating the expression of the adhesion molecules ICAM-I and VCAM-I and the chemoattractants CCL-2, CXCL-8 and CXCL-1. IL-32-mediated expression of these chemokines was sufficient to drive monocyte transmigration in vitro. Finally, we demonstrate that IL-32 expression in both PLWH and controls correlates with the carotid artery stiffness, measured by the cumulated lateral translation. These results suggest a role for IL-32-mediated endothelial cell dysfunction in dysregulation of the blood vessel wall and that IL-32 may represent a therapeutic target to prevent CVD in PLWH.

New indices of arterial stiffness correlate with disease severity and mid-term prognosis in acute decompensated heart failure

Arterial stiffness has been implicated in pathophysiology of heart failure (HF) since it is involved in the ventricular-vascular coupling. Recently, new indices obtained by a cuff oscillometric technique, the arterial velocity pulse index (AVI) for the stiffness of central arteries and the arterial pressure volume index (API) for the stiffness of peripheral arteries have been developed and validated. However, the AVI and API measurement has not been attempted in HF population. This study aimed to investigate the relationship between the AVI, API and clinical parameters and outcomes in HF patients. A prospective cohort of patients with acute decompensated HF were enrolled within 6 months, who were admitted to a tertiary referral hospital in China. Measurement of the AVI and API (AVE-1500, Shisei Datum, Tokyo, Japan) was performed on the day of admission and discharge. Patients were followed up to 6 months for the composite endpoint of all-cause death and rehospitalization for HF. A total of 127 patients were recruited for analysis (60 ± 15 years, 70% male). 80% of the patients were in New York Heart Association (NYHA) Class III or IV at admission with mean left ventricular ejection fraction (LVEF) of 34 ± 9%. During hospitalization, all patients received guideline-directed medical therapy if not contraindicated. The AVI (27.3 ± 5.0 vs. 28.6 ± 6.7, P = 0.002) and API (24.9 ± 4.9 vs. 26.0 ± 6.5, P = 0.05) were lower at discharge than at admission. By dividing the patients into mild to severe group based on systolic blood pressure (SBP) and LVEF or into tertiles according to the amino-terminal pro-brain natriuretic peptide (NT-proBNP), transmitral E velocity over mitral annular e' velocity (E/e' ratio), it was observed that the AVI increased with a higher level of NT-proBNP (P for trend < 0.001), a larger E/e' (P for trend < 0.001) and a lower LVEF (P for trend = 0.0183), while the API increased as the E/e' and systolic blood pressure became higher (both P for trend < 0.05). The improvement in AVI at discharge was correlated with LVEF (R = - 0.3024, P < 0.05) and NT-proBNP improvement (R = 0.3118, P < 0.05), while the change in API was positively correlated with SBP change (R = 0.3897, P < 0.001). In 6 months after discharge, there were 52 predefined events including 15 deaths and 44 rehospitalization for HF. Apart from the level of NT-proBNP, the AVI at discharge of ≥ 26 showed a trend of being associated with the composite outcome (HR 2.747, 95% CI 1.411-5.349, P < 0.001 for univariate analysis; HR 1.864, 95% CI 0.892-3.893, P = 0.09761 for multivariate analysis). New noninvasive arterial stiffness indices as the AVI and API reflected severity of illness and midterm prognosis in admitted HF patients. Further studies are warranted for understanding its mechanisms and developing clinical applications.

Smooth Muscle Cell-Mineralocorticoid Receptor as a Mediator of Cardiovascular Stiffness With Aging

Stiffening of the vasculature with aging is a strong predictor of adverse cardiovascular events, independent of all other risk factors including blood pressure, yet no therapies target this process. MRs (mineralocorticoid receptors) in smooth muscle cells (SMCs) have been implicated in the regulation of vascular fibrosis but have not been explored in vascular aging. Comparing SMC-MR-deleted male mice to MR-intact littermates at 3, 12, and 18 months of age, we demonstrated that aging-associated vascular stiffening and fibrosis are mitigated by MR deletion in SMCs. Progression of cardiac stiffness and fibrosis and the decline in exercise capacity with aging were also mitigated by MR deletion in SMC. Vascular gene expression profiling analysis revealed that MR deletion in SMC is associated with recruitment of a distinct antifibrotic vascular gene expression program with aging. Moreover, long-term pharmacological inhibition of MR in aged mice prevented the progression of vascular fibrosis and stiffness and induced a similar antifibrotic vascular gene program. Finally, in a small trial in elderly male humans, short-term MR antagonism produced an antifibrotic signature of circulating biomarkers similar to that observed in the vasculature of SMC-MR-deleted mice. These findings suggest that SMC-MR contributes to vascular stiffening with aging and is a potential therapeutic target to prevent the progression of aging-associated vascular fibrosis and stiffness.

Age and cigarette smoking modulate the relationship between pulmonary function and arterial stiffness in heart failure patients

The aim of this study was to assess the relationship between arterial stiffness and pulmonary function in chronic heart failure (CHF).Outpatients previously diagnosed as CHF were enrolled between April 2008 and March 2010, and submitted to arterial stiffness measurement and lung function assessment. Spirometry was performed by measuring forced vital capacity (FVC), the fraction of predicted FVC, forced expiratory volume in 1 second (FEV1), the percentage of predicted FEV1 in 1 second, FEV1 to FVC ratio, and the percentage of predicted FEV1/FVC. Cardio-ankle vascular index (CAVI) was considered for the estimation of arterial stiffness.The 354 patients assessed included 315 nonsmokers, and were 68.2 ± 7.2 years' old. Unadjusted correlation analyses demonstrated CAVI was positively related to age (r = 0.3664, P < 0.0001), and negatively related to body mass index (BMI, r = -0.2040, P = 0.0001), E/A ratio (r = -0.1759, P = 0.0010), and FEV1 (r = -0.2987, P < 0.0001). Stepwise multivariate regression analyses showed age (r = 0.2391, P < 0.0001), BMI (r = -0.2139, P < 0.0001), smoking (r = 0.1211, P = 0.0130), E/A ratio (r = -0.1082, P = 0.0386), and FEV1 (r = -0.2550, P < 0.0001) were independent determinants of CAVI. In addition, there is a significant interaction between CAVI and forced expiratory volume in 1 second (FEV1) in relation to age (Pint < 0.0001) and smoking (Pint = 0.0001). Meanwhile, pulmonary function was not associated with BMI or E/A ratio.These findings demonstrated that reduced pulmonary function is associated with the increased CAVI, and had an interactive effect with age and smoking on CAVI in patients with CHF.

Pulmonary Function and Arterial Stiffness in Chronic Heart Failure

Arterial stiffness contributes to heart failure and is decreased by angiotensin receptor blockers (ARBs). This cross-sectional study aimed to assess associations of lung function and ARB with arterial stiffness in patients with chronic heart failure. 354 outpatients (168 males; 186 females; 68.2 ± 7.2 years old) with chronic heart failure were evaluated. Lung function parameters, including forced vital capacity (FVC), forced expiratory volume in 1 s (FEV₁), and FEV₁ to FVC ratio (FEV₁/FVC), were assessed. The cardio-ankle vascular index (CAVI) was used to estimate arterial stiffness. Unadjusted correlation analyses revealed a positive association of CAVI with ARB but not ACEI, and a negative correlation with FEV₁ (r = −0.2987, p < 0.0001). Multiple stepwise regression analyses showed that ARB and FEV1 (p < 0.0001) were independent predicting factors for CAVI. These findings suggest that reduced pulmonary function is associated with increased CAVI. Pulmonary function protection could be used to improve the prognosis in heart failure, but additional studies are necessary.

Early Antiretroviral Therapy at High CD4 Counts Does Not Improve Arterial Elasticity: A Substudy of the Strategic Timing of AntiRetroviral Treatment (START) Trial

Background.

Both human immunodeficiency virus (HIV) infection and antiretroviral therapy (ART) may increase cardiovascular disease (CVD) risk. Vascular function assessments can be used to study CVD pathogenesis. We compared the effect of immediate versus deferred ART initiation at CD4 counts >500 cells/mm³ on small arterial elasticity (SAE) and large artery elasticity (LAE).

Methods.

Radial artery blood pressure waveforms were recorded noninvasively. Small arterial elasticity and LAE were derived from analysis of the diastolic pulse waveform. Randomized treatment groups were compared with linear models at each visit and longitudinal mixed models.

Results.

Study visits involved 332 participants in 8 countries: mean (standard deviation [SD]) age 35 (10), 70% male, 66% nonwhite, 30% smokers, and median CD4 count 625 cells/mm³ and 10-year Framingham risk score for CVD 1.7%. Mean (SD) SAE and LAE values at baseline were 7.3 (2.9) mL/mmHg × 100 and 16.6 (4.1) mL/mmHg × 10, respectively. Median time on ART was 47 and 12 months in the immediate and deferred ART groups, respectively. The treatment groups did not demonstrate significant within-person changes in SAE or LAE during the follow-up period, and there was no difference in mean change from baseline between treatment groups. The lack of significant differences persisted after adjustment, when restricted to early or late changes, after censoring participants in deferred group who started ART, and among subgroups defined by CVD and HIV risk factors.

Conclusions.

Among a diverse global population of HIV-positive persons with high CD4 counts, these randomized data suggest that ART treatment does not have a substantial influence on vascular function among younger HIV-positive individuals with preserved immunity.

An insight into elasticity analysis of common carotid artery using ultrasonography

Elastance is a distinguished marker in diagnosing various arterial diseases as studies have reported carotid artery–related diseases linked with stiffness index (β) values greater than 5. This study was to estimate elasticity of common carotid artery by measuring the diameter during systolic and diastolic phases using pixel tracing of successive frames and blood pressure. The B-mode ultrasonography video containing arterial wall motion was captured and fragmented into image frames. Each pixel on the greyscale image was converted into RGB intensity values. The diameter of the artery as well as the thickness of the wall was measured by tracing the pixel displacements from successive frames during arterial pulsation. The study was conducted on 19 subjects aged 25–40 years. The systolic and diastolic carotid artery lumen diameters and carotid intima-media thickness were calculated as 7.1 ± 0.7, 6.3 ± 0.6 and 0.5 ± 0.05 mm (mean ± standard deviation), respectively. The mean stiffness index (β), Peterson’s modulus and Young’s modulus of elasticity were 5.2 ± 1.1, 69 ± 15 kPa and 453 ± 99 kPa, respectively. The pixel displacements in tunica intima, tunica media and tunica adventitia were not homogeneous, due to varied macro-constituents such as endothelial tissues, smooth muscle cells, elastin lamina, fibrous tissue and micro-constituents such as collagen, fibroblast and elastin. We found that women have smaller arteries, and the stiffness increased during the systolic phase.

Effects of chronic carotid baroreceptor activation on arterial stiffness in severe heart failure

BACKGROUND

Heart failure with reduced ejection fraction (HFrEF) is characterized by activation of the sympathetic nervous system and increased arterial stiffness, leading to an impaired ventricular-vascular coupling. Baroreflex activation therapy (BAT) has been shown to reduce muscle sympathetic nerve activity (MSNA) and improve clinical status of patients with HFrEF. The purpose of this investigation was to determine the effects of BAT on arterial stiffness in HFrEF.

METHODS AND RESULTS

MSNA, clinical variables, and parameters of central blood pressure (BP) and arterial stiffness were collected in 18 NYHA Class III HFrEF patients, nine receiving BAT and nine continuing with optimal medical management alone. Patients were followed for 3 months, with measurements at that time compared to baseline evaluation. Baseline characteristics of the groups were well matched. At 3 months, BAT did not improve central BP and arterial stiffness despite a significant amelioration of MSNA, NYHA class, Minnesota living with heart failure questionnaire score, number of heart failure medications and six-minute walking distance. The control group exhibited no significant changes in all the measured variables.

CONCLUSIONS

Despite significant reductions in MSNA and clinical improvement, BAT does not appear to chronically modify arterial stiffness within this HFrEF cohort. Additional study is required to determine if this result applies to the HFrEF population as a whole.

Direct role for smooth muscle cell mineralocorticoid receptors in vascular remodeling: novel mechanisms and clinical implications

The mineralocorticoid receptor (MR) is a key regulator of blood pressure. MR antagonist drugs are used to treat hypertension and heart failure, resulting in decreased mortality by mechanisms that are not completely understood. In addition to the kidney, MR is also expressed in the smooth muscle cells (SMCs) of the vasculature, where it is activated by the hormone aldosterone and affects the expression of genes involved in vascular function at the cellular and systemic levels. Following vascular injury due to mechanical or physiological stresses, vessels undergo remodeling resulting in SMC hypertrophy, migration, and proliferation, as well as vessel fibrosis. Exuberant vascular remodeling is associated with poor outcomes in cardiovascular patients. This review compiles recent findings on the specific role of SMC-MR in the vascular remodeling process. The development and characterization of a SMC-specific MR-knockout mouse has demonstrated a direct role for SMC-MR in vascular remodeling. Additionally, several novel mechanisms contributing to SMC-MR-mediated vascular remodeling have been identified and are reviewed here, including Rho-kinase signaling, placental growth factor signaling through vascular endothelial growth factor type 1 receptor, and galectin signaling.

Serum high-density lipoprotein cholesterol and progression to arterial stiffness in middle-aged and elderly Chinese

BACKGROUND AND AIMS

Low high-density lipoprotein cholesterol (HDL-c) is a risk factor for cardiovascular disease. Brachial-ankle pulse wave velocity (baPWV) is an indicator of arterial stiffness, which is recognized as a predictor of cardiovascular disease. The aim of this study was to investigate the association between HDL-c and baPWV among middle-aged and elderly Chinese.

METHODS

A total number of 1133 Chinese (430 men, 703 women) aged from 50 to 90 years old were recruited from Shanghai downtown district. The baPWV and major cardiovascular risk factors of the participants were measured.

RESULTS

Serum HDL-c was negatively correlated with baPWV (r = -0.143, P < 0.001) after adjustment for age and gender. Multivariate linear regression analysis demonstrated that age (P < 0.001), systolic blood pressure (P < 0.001), HDL-c (P < 0.001), smoking (P = 0.001), BMI (P = 0.002), fasting plasma glucose (P = 0.004), and white blood cell (P = 0.005) were independently associated with baPWV. After multiple adjustments, participants in the highest quartile of HDL-c had an odds ratio of 0.442 (95% CI 0.268-0.729) for developing high arterial stiffness compared with participants in the lowest quartile. The association remained significant after further adjustment for major cardiovascular risk factors.

CONCLUSION

HDL-c has an independent protective effect on arterial stiffness in middle-aged and elderly Chinese. Early detection of HDL-c level is important in high risk populations with arterial stiffness. Increasing HDL-c level may be an attractive therapeutic target for the prevention of arterial function and subsequent disease.

Measurement of the uniaxial mechanical properties of healthy and atherosclerotic human coronary arteries

Atherosclerosis is a common arterial disease which alters the stiffness of arterial wall. Arterial stiffness is related to many cardiovascular diseases. In this investigation, maximum stress and strain as well as physiological and maximum elastic modulus of 22 human coronary arteries are measured. In addition, the force-displacement diagram of human coronary artery is obtained to discern the alterations between the healthy and atherosclerotic arterial wall stiffness. The age of each specimen and its effect on the elastic modulus of human coronary arteries is also considered. Twenty-two human coronary arteries, including eight atherosclerotic and fourteen healthy arteries are excised within 5 hours post-mortem. Samples are mounted on a tensile-testing machine and force is applied until breakage occurs. Elastic modulus coefficient of each specimen is calculated to compare the stiffness of healthy and atherosclerotic coronary arteries. The results show that the atherosclerotic arteries bear 44.55% more stress and 34.61% less strain compared to the healthy ones. The physiological and maximum elastic moduli of healthy arteries are 2.53 and 2.91 times higher than that of atherosclerotic arteries, respectively. The age of specimens show no correlation with the arterial wall stiffness. A combination of biomechanics and mathematics is used to characterize the mechanical properties of human coronary arteries. These results could be utilized to understand the extension and rupture mechanism of coronary arteries and has implications for interventions and surgeries, including balloon-angioplasty, bypass, and stenting.