Large Artery Stiffness, Microvascular Function, and Cardiovascular Risk

Hypertension combined with atherosclerosis increases the risk of heart failure in patients with diabetes

The increase in heart failure risk in the diabetic population when hypertension and atherosclerosis are both present is still inconclusive. The aim of this study was to explore the effects of hypertension combined with atherosclerosis in diabetic population on the risk of heart failure. We selected 10,711 patients with diabetes who participated in the Kailuan study and completed brachial-ankle pulse wave velocity (baPWV) testing for statistical analysis. The subjects were divided into the non-hypertensive non-atherosclerotic, hypertensive, atherosclerotic, and hypertensive atherosclerotic groups based on their history of hypertension and atherosclerosis. At a median follow-up of 4.15 years, 227 cases of heart failure occurred. Compared with the non-hypertensive non-atherosclerotic group, the multifactorial Cox proportional risk regression model showed that the hazard ratio (HR) for heart failure in the hypertensive atherosclerotic group was 3.08 (95% confidence interval [CI]: 1.32-7.16), whereas the HR decreased to 2.38 (95% CI: 1.01-5.63) after gradual correction of lipid-lowering, glucose-lowering, and antihypertensive drugs. The subgroup analysis and sensitivity analysis were consistent with that of total population. In conclusion, patients with diabetes exposed to both hypertension and atherosclerosis had an increased heart failure risk, which was attenuated by the use of lipid-lowering, glucose-lowering, and antihypertensive drugs.

Coronary Microvascular Dysfunction and Hypertension: A Bond More Important than We Think

Coronary microvascular dysfunction (CMD) is a clinical entity linked with various risk factors that significantly affect cardiac morbidity and mortality. Hypertension, one of the most important, causes both functional and structural alterations in the microvasculature, promoting the occurrence and progression of microvascular angina. Endothelial dysfunction and capillary rarefaction play the most significant role in the development of CMD among patients with hypertension. CMD is also related to several hypertension-induced morphological and functional changes in the myocardium in the subclinical and early clinical stages, including left ventricular hypertrophy, interstitial myocardial fibrosis, and diastolic dysfunction. This indicates the fact that CMD, especially if associated with hypertension, is a subclinical marker of end-organ damage and heart failure, particularly that with preserved ejection fraction. This is why it is important to search for microvascular angina in every patient with hypertension and chest pain not associated with obstructive coronary artery disease. Several highly sensitive and specific non-invasive and invasive diagnostic modalities have been developed to evaluate the presence and severity of CMD and also to investigate and guide the treatment of additional complications that can affect further prognosis. This comprehensive review provides insight into the main pathophysiological mechanisms of CMD in hypertensive patients, offering an integrated diagnostic approach as well as an overview of currently available therapeutical modalities.

Associations of Cerebrovascular Regulation and Arterial Stiffness With Cerebral Small Vessel Disease: A Systematic Review and Meta-Analysis

BACKGROUND

Cerebral small vessel disease (cSVD) is a major contributing factor to ischemic stroke and dementia. However, the vascular pathologies of cSVD remain inconclusive. The aim of this systematic review and meta-analysis was to characterize the associations between cSVD and cerebrovascular reactivity (CVR), cerebral autoregulation, and arterial stiffness (AS).

METHODS AND RESULTS

MEDLINE, Web of Science, and Embase were searched from inception to September 2023 for studies reporting CVR, cerebral autoregulation, or AS in relation to radiological markers of cSVD. Data were extracted in predefined tables, reviewed, and meta-analyses performed using inverse-variance random effects models to determine pooled odds ratios (ORs). A total of 1611 studies were identified; 142 were included in the systematic review, of which 60 had data available for meta-analyses. Systematic review revealed that CVR, cerebral autoregulation, and AS were consistently associated with cSVD (80.4%, 78.6%, and 85.4% of studies, respectively). Meta-analysis in 7 studies (536 participants, 32.9% women) revealed a borderline association between impaired CVR and cSVD (OR, 2.26 [95% CI, 0.99-5.14]; P=0.05). In 37 studies (27 952 participants, 53.0% women) increased AS, per SD, was associated with cSVD (OR, 1.24 [95% CI, 1.15-1.33]; P<0.01). Meta-regression adjusted for comorbidities accounted for one-third of the AS model variance (R2=29.4%, Pmoderators=0.02). Subgroup analysis of AS studies demonstrated an association with white matter hyperintensities (OR, 1.42 [95% CI, 1.18-1.70]; P<0.01).

CONCLUSIONS

The collective findings of the present systematic review and meta-analyses suggest an association between cSVD and impaired CVR and elevated AS. However, longitudinal investigations into vascular stiffness and regulatory function as possible risk factors for cSVD remain warranted.

Mechanistic insights on age-related changes in heart-aorta-brain hemodynamic coupling using a pulse wave model of the entire circulatory system

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.

Genetic analyses identify brain structures related to cognitive impairment associated with elevated blood pressure

BACKGROUND AND AIMS

Observational studies have linked elevated blood pressure (BP) to impaired cognitive function. However, the functional and structural changes in the brain that mediate the relationship between BP elevation and cognitive impairment remain unknown. Using observational and genetic data from large consortia, this study aimed to identify brain structures potentially associated with BP values and cognitive function.

METHODS AND RESULTS

Data on BP were integrated with 3935 brain magnetic resonance imaging-derived phenotypes (IDPs) and cognitive function defined by fluid intelligence score. Observational analyses were performed in the UK Biobank and a prospective validation cohort. Mendelian randomisation (MR) analyses used genetic data derived from the UK Biobank, International Consortium for Blood Pressure, and COGENT consortium. Mendelian randomisation analysis identified a potentially adverse causal effect of higher systolic BP on cognitive function [-0.044 standard deviation (SD); 95% confidence interval (CI) -0.066, -0.021] with the MR estimate strengthening (-0.087 SD; 95% CI -0.132, -0.042), when further adjusted for diastolic BP. Mendelian randomisation analysis found 242, 168, and 68 IDPs showing significant (false discovery rate P < 0.05) association with systolic BP, diastolic BP, and pulse pressure, respectively. Most of these IDPs were inversely associated with cognitive function in observational analysis in the UK Biobank and showed concordant effects in the validation cohort. Mendelian randomisation analysis identified relationships between cognitive function and the nine of the systolic BP-associated IDPs, including the anterior thalamic radiation, anterior corona radiata, or external capsule.

CONCLUSION

Complementary MR and observational analyses identify brain structures associated with BP, which may be responsible for the adverse effects of hypertension on cognitive performance.

An inflammatory aging clock (iAge) based on deep learning tracks multimorbidity, immunosenescence, frailty and cardiovascular aging

While many diseases of aging have been linked to the immunological system, immune metrics capable of identifying the most at-risk individuals are lacking. From the blood immunome of 1,001 individuals aged 8-96 years, we developed a deep-learning method based on patterns of systemic age-related inflammation. The resulting inflammatory clock of aging (iAge) tracked with multimorbidity, immunosenescence, frailty and cardiovascular aging, and is also associated with exceptional longevity in centenarians. The strongest contributor to iAge was the chemokine CXCL9, which was involved in cardiac aging, adverse cardiac remodeling and poor vascular function. Furthermore, aging endothelial cells in human and mice show loss of function, cellular senescence and hallmark phenotypes of arterial stiffness, all of which are reversed by silencing CXCL9. In conclusion, we identify a key role of CXCL9 in age-related chronic inflammation and derive a metric for multimorbidity that can be utilized for the early detection of age-related clinical phenotypes.

Pathophysiology and consequences of arterial stiffness in children with chronic kidney disease

Changes in arterial structure and function are seen early in the course of chronic kidney disease (CKD) and have been causally associated with cardiovascular (CV) morbidity. Numerous potential injuries encompassing both traditional and uremia-specific CV risk factors can induce structural arterial changes and accelerate arterial stiffening. When the buffering capacity of the normally elastic arteries is reduced, damage to vulnerable microcirculatory beds can occur. Moreover, the resultant increase to cardiac afterload contributes to the development of left ventricular hypertrophy and cardiac dysfunction. Adult studies have linked arterial stiffness with increased risk of mortality, CV events, cognitive decline, and CKD progression. Pulse wave velocity (PWV) is currently the gold standard of arterial stiffness assessment but its measurement in children is challenging due to technical difficulties and physiologic aspects related to growth and poor standardization between algorithms for calculating PWV. Nevertheless, studies in pediatric CKD have reported increased arterial stiffness in children with advanced CKD, on dialysis, and after kidney transplantation. Development of arterial stiffness in children with CKD is closely related to mineral-bone disease and hypertension, but other factors may also play a significant role. The clinical relevance of accelerated arterial stiffness in childhood on cardiovascular outcomes in adult life remains unclear, and prospective studies are needed. In this review we discuss mechanisms leading to arterial stiffness in CKD and its clinical implications, along with issues surrounding the technical aspects of arterial stiffness assessment in children.

The association between carotid disease, arterial stiffness and diabetic retinopathy in type 2 diabetes: the Fremantle Diabetes Study Phase II

AIM

To determine whether macrovascular disease assessed by carotid ultrasonography and arterial stiffness by pulse wave velocity are independently associated with diabetic retinopathy in type 2 diabetes.

METHODS

A random subgroup of surviving participants with type 2 diabetes from the Fremantle Diabetes Study Phase II were invited to take part in this sub-study in 2018-2019. In addition to standardized questionnaires, a physical examination and fasting biochemical tests, each underwent dilated colour fundus photography, carotid arterial ultrasonography with measurement of the intima-media thickness (IMT) and quantification of the degree of stenosis, and pulse wave analysis calculation of the carotid-femoral pulse wave velocity (cfPWV). The cross-sectional association between arterial disease parameters and diabetic retinopathy was assessed using generalized estimating equation models which enabled both eyes to be included in the analysis.

RESULTS

Some 270 participants [mean ± sd age 72 ± 9 years, 153 (57%) men and median (IQR) diabetes duration 15 (11-22) years] were included in analysis. Of 524 assessable eyes, 82 (16%) had diabetic retinopathy. In multivariable analysis, significant independent associates of diabetic retinopathy were age at diabetes diagnosis (inversely), HbA_1c , insulin treatment and urinary albumin to creatinine ratio (all P ≤ 0.022), as well as cfPWV [odds ratio (OR) 1.13, 95% confidence interval (CI) 1.03, 1.23 per 1 m/s increase; P = 0.008] and common carotid artery (CCA) IMT ≥1 mm (OR 2.95, 95% CI 1.21, 7.23; P = 0.018).

CONCLUSIONS

The association between diabetic retinopathy and CCA IMT suggests that carotid disease may share cardiovascular risk factors with diabetic retinopathy. The association between diabetic retinopathy and cfPWV may reflect the consequences of altered intravascular haemodynamics.

Renal Sympathetic Denervation in Patients With Heart Failure With Preserved Ejection Fraction

BACKGROUND

Arterial hypertension is the most common comorbidity in patients with heart failure with preserved ejection fraction (HFpEF) and mediates adverse hemodynamics through related aortic stiffness and increased pulsatile load. We aimed to investigate the clinical and hemodynamic implications of renal sympathetic denervation (RDN) in patients with HFpEF and uncontrolled arterial hypertension.

METHODS

Patients undergoing RDN between 2011 and 2018 in a single-center were retrospectively analyzed and classified as HFpEF (n=99) or no HF (n=65). Stroke volume index and aortic distensibility were measured through cardiac magnetic resonance imaging, and left ventricular (LV) systolic and diastolic properties were assessed echocardiographically.

RESULTS

At baseline, patients with HFpEF had higher stroke volume index (median 40 [interquartile range, 33-48] versus 33 [26-40] mL/m², P=0.002), pulse pressure (69 [63-77] versus 61 [55-67] mm Hg, P<0.001), but lower LV-VPES_100mm Hg (18 [10-28] versus 24 [15-40] mL, P=0.007) and aortic distensibility (1.5 [1.1-2.6] versus 2.7 [1.1-3.5] 10^-3 mm Hg^-1, P=0.013) as compared to no-HF patients. Systolic blood pressure decreased comparable in patients with HFpEF and no-HF patients following RDN (-9 [-16 to -2], P<0.001). After RDN stroke volume index (-3 [-9 to +3] mL/m², P=0.011) decreased and aortic distensibility (0.2 [-0.1 to +1.1] 10^-3 mm Hg^-1, P=0.007) and systolic stiffness (P<0.001) increased in HFpEF patients. LV diastolic stiffness and LV filling pressures as well as NT-proBNP (N-terminal pro-B-type natriuretic peptide) decreased after RDN in patients with HFpEF (P=0.032, P=0.043, and P<0.001, respectively).

CONCLUSIONS

Patients with HFpEF undergoing RDN showed increased stroke volume index, vascular, and LV stiffness as compared to no-HF patients. Following RDN those hemodynamic alterations and reduced systolic and diastolic LV stiffness were partly normalized, implying RDN might be a potential therapeutic strategy for arterial hypertension and HFpEF.

Vascular smooth muscle cell-specific progerin expression in a mouse model of Hutchinson-Gilford progeria syndrome promotes arterial stiffness: Therapeutic effect of dietary nitrite

Vascular stiffness is a major cause of cardiovascular disease during normal aging and in Hutchinson-Gilford progeria syndrome (HGPS), a rare genetic disorder caused by ubiquitous progerin expression. This mutant form of lamin A causes premature aging associated with cardiovascular alterations that lead to death at an average age of 14.6 years. We investigated the mechanisms underlying vessel stiffness in LmnaG609G/G609G mice with ubiquitous progerin expression, and tested the effect of treatment with nitrites. We also bred LmnaLCS/LCS Tie2Cre+/tg and LmnaLCS/LCS SM22αCre+/tg mice, which express progerin specifically in endothelial cells (ECs) and in vascular smooth muscle cells (VSMCs), respectively, to determine the specific contribution of each cell type to vascular pathology. We found vessel stiffness and inward remodeling in arteries of LmnaG609G/G609G and LmnaLCS/LCS SM22αCre+/tg , but not in those from LmnaLCS/LCS Tie2Cre+/tg mice. Structural alterations in aortas of progeroid mice were associated with decreased smooth muscle tissue content, increased collagen deposition, and decreased transverse waving of elastin layers in the media. Functional studies identified collagen (unlike elastin and the cytoskeleton) as an underlying cause of aortic stiffness in progeroid mice. Consistent with this, we found increased deposition of collagens III, IV, V, and XII in the media of progeroid aortas. Vessel stiffness and inward remodeling in progeroid mice were prevented by adding sodium nitrite in drinking water. In conclusion, LmnaG609G/G609G arteries exhibit stiffness and inward remodeling, mainly due to progerin-induced damage to VSMCs, which causes increased deposition of medial collagen and a secondary alteration in elastin structure. Treatment with nitrites prevents vascular stiffness in progeria.

Subclinical parameters of arterial stiffness and arteriosclerosis correlate with QRISK3 in systemic lupus erythematosus

It is well known that cardiovascular diseases (CVD) are a major contributor of death in systemic lupus erythematosus (SLE) as well in other rheumatic illness. In the last decades, there has been a growing development of different methodologies with the purpose of early detection of CVD. Objective: The aim of this study is to correlate the usefulness of subclinical parameters of vascular aging and QRISK 3–2017 score for early detection of CVD in SLE. Methods: Clinical assessment including systemic lupus erythematosus disease activity index (SLEDAI) and systemic lupus international collaborating clinics / american college of rheumatology damage index (SLICC/ACR DI), laboratory measurements, carotid ultrasound examination, carotid intima media thickness (cIMT) measurement, carotid distention and diameter analysis, arterial stiffness measurement measured by tonometry and QRISK 3–2017 were done. All results were analyzed by SPSS 24 software. Results: We observed correlation between QRISK3 and mean cIMT (rs = 0.534, P < 0.001), PWV (rs = 0.474, P < 0.001), cfPWV (rs = 0.569, P < 0.001) and distensibility (rs = -0.420, P = 0.006). Consistent with above, SLE patients in middle and high risk QRISK 3–2017 showed increased arterial stiffness versus low risk group. Conclusions: We encourage to the rheumatology community to assess cardiovascular risk in SLE patients with QRISK 3–2017 risk calculator as an alternative method at the outpatient clinic along a complete cardiovascular evaluation when appropriate.

Deep Phenotyping of Systemic Arterial Hemodynamics in HFpEF (Part 2): Clinical and Therapeutic Considerations

Multiple phase III trials over the last few decades have failed to demonstrate a clear benefit of various pharmacologic interventions in heart failure with a preserved left ventricular (LV) ejection fraction (HFpEF). Therefore, a better understanding of its pathophysiology is important. An accompanying review describes key technical and physiologic aspects regarding the deep phenotyping of arterial hemodynamics in HFpEF. This review deals with the potential of this approach to enhance our clinical, translational, and therapeutic approach to HFpEF. Specifically, the role of arterial hemodynamics is discussed in relation to (1) the pathophysiology of left ventricular diastolic dysfunction, remodeling, and fibrosis, (2) impaired oxygen delivery to peripheral skeletal muscle, which affects peripheral oxygen extraction, (3) the frequent presence of comorbidities, such as renal failure and dementia in this population, and (4) the potential to enhance precision medicine approaches. A therapeutic approach to target arterial hemodynamic abnormalities that are prevalent in this population (particularly, with inorganic nitrate/nitrite) is also discussed.