Dose-dependent arterial destiffening and inward remodeling after olmesartan in hypertensives with metabolic syndrome

Plasma copeptin and markers of arterial disorder in patients with type 2 diabetes, a cross-sectional study

OBJECTIVES

There is currently limited understanding of the relationship between copeptin, the midregional portion of proadrenomedullin (MRproADM) and the midregional fragment of the N-terminal of proatrial natriuretic peptide (MRproANP), and arterial disorders. Toe brachial index (TBI) and aortic pulse wave velocity (aPWV) are established parameters for detecting arterial disorders. This study evaluated whether copeptin, MRproADM, and MRproANP were associated with TBI and aPWV in patients with type 2 diabetes with no history of cardiovascular disease (CVD).

METHODS

In the CARDIPP study, a cross-sectional analysis of 519 patients with type 2 diabetes aged 55-65 years with no history of CVD at baseline, had complete data on copeptin, MRproADM, MRproANP, TBI, and aPWV was performed. Linear regression analysis was used to investigate the associations between conventional CVD risk factors, copeptin, MRproADM, MRproANP, TBI, and aPWV.

RESULTS

Copeptin was associated with TBI (β-0.0020, CI-0.0035- (-0.0005), p = 0.010) and aPWV (β 0.023, CI 0.002-0.044, p = 0.035). These associations were independent of age, sex, diabetes duration, mean 24-hour ambulatory systolic blood pressure, glycated hemoglobin A1c, total cholesterol, estimated glomerular filtration rate, body mass index, and active smoking.

CONCLUSIONS

Plasma copeptin may be a helpful surrogate for identifying individuals at higher risk for arterial disorders.

TRIAL REGISTRATION

 ClinicalTrials.gov identifier NCT010497377.

Early Cardiac Rehabilitation Improves Carotid Arterial Stiffness in Patients with Myocardial Infarction

Background

Little is known about the effect of cardiac rehabilitation (CR) on carotid arterial stiffness (CAS) in patients with myocardial infarction (MI).

Patients and Methods

Rehabilitation group (B) included 90 patients with MI subjected to CR, control group (K) consisted of 30 patients with MI not participating in CR, and healthy group comprised 38 persons without cardiovascular risk factors. CAS was determined using echo-tracking before and after CR.

Results

At baseline, patients with MI (B+K) presented with significantly higher mean values of CAS parameters: beta-stiffness index (7.1 vs 6.4, p = 0.004), Peterson's elastic modulus (96 kPa vs 77 kPa, p < 0.001) and PWV-beta (6.1 m/s vs 5.2 m/s, p < 0.001) than healthy persons. Age (beta: r = 0.242, p = 0.008; EP: r = 0.250, p = 0.006; PWV-beta: r = 0.224, p = 0.014) and blood pressure: SBP (EP: r = 0.388, PWV-beta: r = 0.360), DBP (AC: r = 0.225) and PP (PWV-beta: r = 0.221) correlated positively with the initial parameters of CAS. Beta-stiffness index (Rho=-0.26, p = 0.04) and PWV-beta (Rho = 0.29, p = 0.03) correlated inversely with peak exercise capacity expressed in METs. After CR, mean values of beta-stiffness index (6.2 vs 7.1, p = 0.016), EP (78 kPa vs 101 kPa, p = 0.001) and PWV-beta (5.4 m/s vs 6.2 m/s, p = 0.001) in group B were significantly lower than in group K. In group B, CAS parameters decreased significantly after CR. Univariate analysis demonstrated that the likelihood of an improvement in CAS after CR was significantly higher in patients with baseline systolic blood pressure <120 mm Hg (OR = 2.74, p = 0.009) and left ventricular ejection fraction <43% (OR = 5.05, p = 0.005).

Conclusion

In patients with MI, CR exerted a beneficial effect on CAS parameters. The improvement in CAS was predicted by lower SBP and LVEF at baseline.

Biomechanics models predict increasing smooth muscle tone as a novel therapeutic target for central arterial dysfunction in hypertension

INTRODUCTION

Vasodilation can paradoxically increase arterial stiffness in older, hypertensive adults. This study modeled increasing smooth muscle tone as a therapeutic strategy to improve central arterial dysfunction in hypertension using participant-specific simulations.

METHODS

Participant-specific models of the carotid artery were parameterized from vascular ultrasound measures of nitroglycerin-induced vasodilation in 18 hypertensive veterans. The acute changes in carotid artery mechanics were simulated for changes of ±2, ±4, and ±6% in smooth muscle tone and ±5, ±10, and ±15 mmHg in mean arterial pressure (MAP). The chronic carotid artery adaptations were simulated based on the hypothesis that the carotid artery will remodel wall-cross sectional area to maintain mechanical homeostasis.

RESULTS

A 6% increase in smooth muscle tone acutely decreased carotid pulse wave velocity from 6.89 ± 1.24 m/s to 5.83 ± 1.73 m/s, and a 15 mmHg decrease in MAP decreased carotid pulse wave velocity to 6.17 ± 1.23 m/s. A 6% increase in smooth muscle tone acutely decreased wall stress from 76.2 ± 12.3 to 64.2 ± 10.4 kPa, and a 15 mmHg decrease in MAP decreased wall stress to 60.6 ± 10.7 kPa. A 6% increase in smooth muscle tone chronically decreased wall cross-sectional area from 18.3 ± 5.4 to 15.2 ± 4.9 mm 2, and a 15 mmHg decrease in MAP decreased wall cross-sectional area to 14.3 ± 4.6 mm 2 .

CONCLUSION

In participant-specific simulation, increasing smooth muscle tone can have a stronger or equivalent effect on carotid artery mechanics compared with decreasing blood pressure. Increasing central arterial smooth muscle tone may be a novel therapeutic target to improve central arterial dysfunction in older, hypertensive adults and should be a focus of future research.

Prognostic impact of changes in aortic stiffness for cardiovascular and mortality outcomes in individuals with type 2 diabetes: the Rio de Janeiro cohort study

BACKGROUND

The prognostic importance of changes in aortic stiffness for the occurrence of adverse cardiovascular outcomes and mortality has never been investigated in patients with type 2 diabetes. We aimed to evaluate it in a cohort of 417 patients.

METHODS

Changes in aortic stiffness were assessed by 2 carotid-femoral pulse wave velocity (CF-PWV) measurements performed over a 4-year period. Multivariable Cox analysis examined the associations between changes in CF-PWV, evaluated as a continuous variable with splines and as categorical ones (quartiles and stable/reduction/increase subgroups), and the occurrence of total cardiovascular events (CVEs), major adverse CVEs (MACEs), and all-cause and cardiovascular mortality.

RESULTS

Over a median follow-up of 8.2 years after the 2nd CF-PWV measurement, there were 101 total CVEs (85 MACEs) and 135 all-cause deaths (64 cardiovascular). As a continuous variable, the lowest risk nadir was at -2.5%/year of CF-PWV change, with significantly higher risks of mortality associated with CF-PWV increases, but no excess risks at extremes of CF-PWV reduction. Otherwise, in categorical analyses, patients in the 1st quartile (greatest CF-PWV reductions) had excess risks of all-cause and cardiovascular mortality (hazard ratios [HRs]: 2.0-2.7), whereas patients in 3rd quartile had higher risks of all outcomes (HRs: 2.0-3.2), in relation to the lowest risk 2nd quartile subgroup. Patients in the 4th quartile had higher risks of all-cause mortality. Categorization as stable/reduction/increase subgroups was confirmatory, with higher risks at greater reductions (HRs: 1.7-3.3) and at greater increases in CF-PWV (HRs: 1.9-3.4), in relation to those with stable CF-PWV.

CONCLUSIONS

Changes in aortic stiffness, mainly increases and possibly also extreme reductions, are predictors of adverse cardiovascular outcomes and mortality in individuals with type 2 diabetes.

Prognostic Value of Changes in Aortic Stiffness for Cardiovascular Outcomes and Mortality in Resistant Hypertension: a Cohort Study

The prognostic importance of changes in aortic stiffness for the occurrence of adverse cardiovascular outcomes and mortality has never been investigated in patients with resistant hypertension. We aimed to evaluate it in a prospective cohort of 442 resistant hypertension individuals. Changes in aortic stiffness were assessed by 2 carotid-femoral pulse wave velocity (CF-PWV) measurements performed over a median time interval of 4.7 years. Multivariate Cox analysis examined the associations between changes in CF-PWV (evaluated as continuous variables and categorized into quartiles and as increased/persistently high or reduced/persistently low) and the occurrence of total cardiovascular events (CVEs), major adverse CVEs, and cardiovascular/all-cause mortalities. During a median follow-up of 4.1 years after the second CF-PWV measurement, there were 49 total CVEs (42 major adverse CVEs) and 53 all-cause deaths (32 cardiovascular). As continuous variables, increments in absolute and relative changes in CF-PWV were associated with higher risks of CVEs and major adverse CVEs occurrence, but not of mortality. Divided into quartiles of CF-PWV changes, risks increased in the third and fourth quartile subgroups in relation to the reference first quartile subgroup (those with greatest CF-PWV reductions) for all outcomes. Patients who either increased or persisted with high CF-PWV had excess risks of cardiovascular morbidity/mortality, with hazard ratios ranging from 2.7 to 3.0, in relation to those who reduced or persisted with low CF-PWV values. In conclusion, reducing or preventing progression of aortic stiffness was associated with significant cardiovascular protection in patients with resistant hypertension, suggesting that it may be an additional clinical target of antihypertensive treatment.

ACEI/ARB Medication During ICU Stay Decrease All-Cause In-hospital Mortality in Critically Ill Patients With Hypertension: A Retrospective Cohort Study Based on Machine Learning

Background: Hypertension is a rather common comorbidity among critically ill patients and hospital mortality might be higher among critically ill patients with hypertension (SBP ≥ 140 mmHg and/or DBP ≥ 90 mmHg). This study aimed to explore the association between ACEI/ARB medication during ICU stay and all-cause in-hospital mortality in these patients.

Methods: A retrospective cohort study was conducted based on data from Medical Information Mart for Intensive Care IV (MIMIC-IV) database, which consisted of more than 40,000 patients in ICU between 2008 and 2019 at Beth Israel Deaconess Medical Center. Adults diagnosed with hypertension on admission and those had high blood pressure (SBP ≥ 140 mmHg and/or DBP ≥ 90 mmHg) during ICU stay were included. The primary outcome was all-cause in-hospital mortality. Patients were divided into ACEI/ARB treated and non-treated group during ICU stay. Propensity score matching (PSM) was used to adjust potential confounders. Nine machine learning models were developed and validated based on 37 clinical and laboratory features of all patients. The model with the best performance was selected based on area under the receiver operating characteristic curve (AUC) followed by 5-fold cross-validation. After hyperparameter optimization using Grid and random hyperparameter search, a final LightGBM model was developed, and Shapley Additive exPlanations (SHAP) values were calculated to evaluate feature importance of each feature. The features closely associated with hospital mortality were presented as significant features.

Results: A total of 15,352 patients were enrolled in this study, among whom 5,193 (33.8%) patients were treated with ACEI/ARB. A significantly lower all-cause in-hospital mortality was observed among patients treated with ACEI/ARB (3.9 vs. 12.7%) as well as a lower 28-day mortality (3.6 vs. 12.2%). The outcome remained consistent after propensity score matching. Among nine machine learning models, the LightGBM model had the highest AUC = 0.9935. The SHAP plot was employed to make the model interpretable based on LightGBM model after hyperparameter optimization, showing that ACEI/ARB use was among the top five significant features, which were associated with hospital mortality.

Conclusions: The use of ACEI/ARB in critically ill patients with hypertension during ICU stay is related to lower all-cause in-hospital mortality, which was independently associated with increased survival in a large and heterogeneous cohort of critically ill hypertensive patients with or without kidney dysfunction.

Microcirculation and Macrocirculation in Hypertension: A Dangerous Cross-Link?

Microcirculation and macrocirculation are tightly interconnected into a dangerous cross-link in hypertension. Small artery damage includes functional (vasoconstriction, impaired vasodilatation) and structural abnormalities (mostly inward eutrophic remodeling). These abnormalities are major determinants of the increase in total peripheral resistance and mean blood pressure (BP) in primary hypertension, which in the long term induces large artery stiffening. In turn, large artery stiffening increases central systolic and pulse pressures, which are further augmented by wave reflection in response to the structural alterations in small resistance arteries. Finally, transmission of high BP and flow pulsatility to small resistance arteries further induces functional and structural abnormalities, thus leading to increased total peripheral resistance and mean BP, thus perpetuating the vicious circle. Hyperpulsatility, in addition to higher mean BP, exaggerates cardiac, brain, and kidney damages and leads to cardiovascular, cerebral, and renal complications. The dangerous cross-link between micro and macrocirculation can be reversed into a virtuous one by ACE (angiotensin-converting enzyme) inhibitors, sartans, and calcium channel blockers. These three pharmacological classes are more potent than β-blockers and diuretics for reducing arterial stiffness and small artery remodeling. The same ranking was observed for their effectiveness at reducing left ventricular hypertrophy, preserving glomerular filtration rate, and preventing dementia, suggesting that they can act beyond brachial BP reduction, by breaking the micro/macrocirculation vicious circle.

Characterization of the vascular system using overnight wearable-based pulse arrival time and ambulatory blood pressure: A pilot study

Pulse arrival time (PAT) has been broadly investigated for its potential for cuffless blood pressure (BP) estimation and ease of measurement by wearable devices. It is also of great significance to explore whether PAT conveys complementary information to BP for vascular health assessment. In this paper, the differences between the 24-h ambulatory BP and wearable-based PAT were compared among 12 young normotensives and 15 elderly hypertensives in terms of the mean and coefficients of variation (CoVs). The correlations of the nocturnal normalized PAT (n-PAT) and BP with two arterial stiffness-related parameters (i.e., the intrinsic elastic modulus E₀ and the vascular modulation factor α) estimated by a proposed model-based method were also compared. The results showed that the inter-subject variances of the nocturnal average n-PAT were significantly different between the hypertensives and the normotensives (P < 0.001), and the intra-subject CoVs of the nocturnal n-PAT were also significantly different between the two groups (P < 0.05). However, these findings were not shown in the nocturnal BP. The correlation coefficient between the nocturnal average n-PAT and ln(E₀) is larger than that with the nocturnal BP, i.e., 0.91 vs. 0.56. Furthermore, the result also revealed that all the hypertensives receiving antihypertensive medications did not achieve the optimal control of the nocturnal BP while presented diverse arterial stiffness indicated by the nocturnal average n-PAT and ln(E₀). It is concluded that wearable-based PAT contains complementary information about the vascular system to the ambulatory BP, which may be useful for designing effective antihypertensive treatments.

SPARTE Study: Normalization of Arterial Stiffness and Cardiovascular Events in Patients With Hypertension at Medium to Very High Risk

Supplemental Digital Content is available in the text.

The SPARTE study (Strategy for Preventing cardiovascular and renal events based on ARTErial stiffness; URL: https://www.clinicaltrials.gov; Unique identifier: NCT02617238) is a multicenter open-label randomized controlled trial with blinded end point evaluation, undertaken at 25 French research centers in university hospitals. Patients with primary hypertension were randomly assigned (1:1) to a therapeutic strategy targeting the normalization of carotid-femoral pulse wave velocity (PWV) measured every 6 months (PWV group, n=264) versus a classical therapeutic strategy only implementing the European Guidelines for Hypertension Treatment (conventional group, n=272). In the PWV group, the therapeutic strategy used preferably a combination of ACE (angiotensin-converting enzyme) inhibitor or angiotensin receptor blocker and calcium channel blockers, as well as maximal recommended doses of ACE inhibitors and angiotensin receptor blockers. The primary outcome was a combined end point including particularly stroke and coronary events. Secondary outcomes included the time-course changes in brachial office blood pressure (BP), ambulatory BP, PWV, and treatments. After a median follow-up of 48.3 months, there was no significant between-group difference in primary outcome (hazard ratio, 0.74 [95% CI, 0.40–1.38], P=0.35). In the PWV group, combinations of renin-angiotensin-system blockers and calcium channel blockers were prescribed at higher dosage (P=0.028), office and ambulatory systolic blood pressure and diastolic blood pressure decreased more (P<0.001 and P<0.01, respectively), and PWV increased less (P=0.0003) than in the conventional group. The SPARTE study lacked sufficient statistical power to demonstrate its primary outcome. However, it demonstrated that a PWV-driven treatment for hypertension enables to further reduce office and ambulatory systolic blood pressure and diastolic blood pressure and prevent vascular aging in patients with hypertension at medium-to-very-high risk, compared with strict application of guidelines.

Guide de Pratique Clinique. Prise en charge de l’hypertension artérielle chez l’adulte en Tunisie

Ce document a été réalisé dans le cadre d'une collaboration entre l'Instance Nationale de l’Évaluation et de l'Accréditation en Santé (INEAS), la Société Tunisienne de Cardiologie et de Chirurgie Cardiovasculaire (STCCCV) et la Caisse Nationale d’Assurance Maladie (CNAM).

Arterial Stiffness and Cardiovascular Risk in Hypertension

Arterial stiffness, a leading marker of risk in hypertension, can be measured at material or structural levels, with the latter combining effects of the geometry and composition of the wall, including intramural organization. Numerous studies have shown that structural stiffness predicts outcomes in models that adjust for conventional risk factors. Elastic arteries, nearer to the heart, are most sensitive to effects of blood pressure and age, major determinants of stiffness. Stiffness is usually considered as an index of vascular aging, wherein individuals excessively affected by risk factor exposure represent early vascular aging, whereas those resistant to risk factors represent supernormal vascular aging. Stiffness affects the function of the brain and kidneys by increasing pulsatile loads within their microvascular beds, and the heart by increasing left ventricular systolic load; excessive pressure pulsatility also decreases diastolic pressure, necessary for coronary perfusion. Stiffness promotes inward remodeling of small arteries, which increases resistance, blood pressure, and in turn, central artery stiffness, thus creating an insidious feedback loop. Chronic antihypertensive treatments can reduce stiffness beyond passive reductions due to decreased blood pressure. Preventive drugs, such as lipid-lowering drugs and antidiabetic drugs, have additional effects on stiffness, independent of pressure. Newer anti-inflammatory drugs also have blood pressure independent effects. Reduction of stiffness is expected to confer benefit beyond the lowering of pressure, although this hypothesis is not yet proven. We summarize different steps for making arterial stiffness measurement a keystone in hypertension management and cardiovascular prevention as a whole.

Role of arterial impairment in preeclampsia: should the paradigm shift?

Preeclampsia is a worldwide pregnancy complication with serious short- and long-term maternal and neonatal consequences. Our understanding of preeclampsia pathophysiology has significantly evolved over the last decades with the recognition that impaired arterial function and structure may occur early in the course of pregnancy, preceding the clinic-humoral syndrome and driving long-term cardiovascular disease risk in the future of these patients. Although an early abnormal placentation may be the inciting event for a large proportion of cases, there is growing evidence that challenges the placental hypothesis in all affected women, since placental histopathology lesions thought to be characteristic are neither sensitive nor specific markers for the disorder. Recent hemodynamic investigations and studies on left ventricular function and structure in women with preeclampsia further challenge this universal paradigm and propose that placental dysfunction could be secondary to a maternal cardiovascular maladaptation to pregnancy in certain patients. Supporting this hypothesis, certain vascular features, which are characteristically enhanced in normal pregnancy allowing a healthy vascular adaptation, are absent in preeclampsia and comparable to the nonpregnant population. However, arterial biomechanics in preeclampsia may only not cope with hemodynamic demands of pregnancy but also impose additional detrimental loads to the maternal heart ("impaired left-ventricle-aorta coupling") and transmit pressure and flow disturbances into the fetoplacental circulation ("impaired large arteries-microcirculation coupling"). In this review, we analyze the major role of the arterial dysfunction in the cardiovascular maladaptation hypothesis of preeclampsia, shed light on its potential etiopathogenic link, and discuss the complementary nature of the placental and cardiovascular theories.

Arterial Stiffness in Aging: Does It Have a Place in Clinical Practice?: Recent Advances in Hypertension

Aortic stiffness increases markedly with age and is associated with excess risk for various adverse clinical outcomes, including heart disease, dementia, and kidney disease. Although evidence for adverse effects of aortic stiffening is overwhelming, integration of direct and indirect measures of aortic stiffness into routine clinical assessment has lagged behind the science. This brief review will examine recent evidence supporting the value of stiffness as an important new risk factor for hypertension and cardiovascular disease and will offer suggestions for incorporating stiffness measures into routine clinical practice.

Predictors of neo-aortic valve regurgitation in the long term after arterial switch operation

Although arterial switch operations (ASOs) have been performed globally to repair d-transposition of the great arteries (d-TGA) in neonates and infants, few studies have been reported regarding the influence of the hemodynamics of patients with d-TGA who have undergone ASO on the development of neo-aortic valve regurgitation (AR). We aimed to investigate the relationship between the hemodynamics and development of AR after ASO in patients with d-TGA by catheter evaluation. This observational study screened 114 consecutive patients who underwent ASO for d-TGA or Taussig-Bing anomaly and who subsequently underwent catheter evaluations in our institution. We reviewed their records for the past 20 years and collected their first catheterization data post-ASO in early childhood. Thirty-six post-ASO patients who underwent catheter evaluations in both the early surgical and long-term phases were finally analyzed. Patients were divided into the following groups according to the presence of significant AR in the long-term phase: the AR group (n = 9 with AR ≥ grade II by the Sellers classification) and the non-AR group (n = 27 with AR < grade II). In the long-term phase, the diastolic blood pressure was significantly lower and the ascending aortic diameter was significantly larger in the AR group than in the non-AR group (p = 0.004 and p = 0.006, respectively). The systolic blood pressure (SBP) and pulse pressure (PP) were similar in both groups. Meanwhile, in the early surgical phase, SBP and PP were significantly higher in the AR group than in the non-AR group (p = 0.029 and p = 0.002, respectively). The receiver operating characteristic curve for late AR showed that the area under the curve for SBP and PP in the early surgical phase were 0.746 and 0.853, respectively. Even though sensitivity analysis was performed, SBP or PP greater than the cutoff value in the early surgical phase was identified as predictors for late AR. Our results suggested that high SBP or PP in the early surgical phase could influence the development of AR in the long term after ASO.

Arterial Stiffness and Hypertension in the Elderly

Hypertension prevalence increases with age. Age and high blood pressure are the two main determinants of arterial stiffness. In elderly hypertensives, large arteries stiffen and systolic and pulse pressures increase, due to wave reflections. A major reason for measuring arterial stiffness in clinical practice in elderly hypertensive patients comes from the repeated demonstration that arterial stiffness and wave reflections have a predictive value for CV events. A large body of evidence has been published during the last two decades, concerning the epidemiology, pathophysiology, and pharmacology of large arteries in hypertension in various settings of age. Particularly, two expert consensus documents have reviewed the methodological agreements for measuring arterial stiffness. The concepts of Early Vascular Aging (EVA) and Supernormal Vascular Aging (SUPERNOVA) help to better understand on which determinants of arterial stiffness it is possible to act, in order to limit target organ damage and cardiovascular complications. This review will address the issues of the cellular and molecular mechanisms of arterial stiffening in elderly hypertensives, the consequences of arterial stiffening on central systolic and pulse (systolic minus diastolic, PP) pressures and target organs, the methodology for measuring arterial stiffness, central pulse pressure and wave reflection, the epidemiological determinants of arterial stiffening in elderly hypertensives, the pharmacology of arterial destiffening, and how the concepts of EVA and SUPERNOVA apply to the detection of organ damage and prevention of CV complications.

Carotid Intima-Media Thickness Progression as Surrogate Marker for Cardiovascular Risk: Meta-Analysis of 119 Clinical Trials Involving 100 667 Patients

BACKGROUND

To quantify the association between effects of interventions on carotid intima-media thickness (cIMT) progression and their effects on cardiovascular disease (CVD) risk.

METHODS

We systematically collated data from randomized, controlled trials. cIMT was assessed as the mean value at the common-carotid-artery; if unavailable, the maximum value at the common-carotid-artery or other cIMT measures were used. The primary outcome was a combined CVD end point defined as myocardial infarction, stroke, revascularization procedures, or fatal CVD. We estimated intervention effects on cIMT progression and incident CVD for each trial, before relating the 2 using a Bayesian meta-regression approach.

RESULTS

We analyzed data of 119 randomized, controlled trials involving 100 667 patients (mean age 62 years, 42% female). Over an average follow-up of 3.7 years, 12 038 patients developed the combined CVD end point. Across all interventions, each 10 μm/y reduction of cIMT progression resulted in a relative risk for CVD of 0.91 (95% Credible Interval, 0.87-0.94), with an additional relative risk for CVD of 0.92 (0.87-0.97) being achieved independent of cIMT progression. Taken together, we estimated that interventions reducing cIMT progression by 10, 20, 30, or 40 μm/y would yield relative risks of 0.84 (0.75-0.93), 0.76 (0.67-0.85), 0.69 (0.59-0.79), or 0.63 (0.52-0.74), respectively. Results were similar when grouping trials by type of intervention, time of conduct, time to ultrasound follow-up, availability of individual-participant data, primary versus secondary prevention trials, type of cIMT measurement, and proportion of female patients.

CONCLUSIONS

The extent of intervention effects on cIMT progression predicted the degree of CVD risk reduction. This provides a missing link supporting the usefulness of cIMT progression as a surrogate marker for CVD risk in clinical trials.

The association of the metabolic syndrome with target organ damage: focus on the heart, brain, and central arteries

INTRODUCTION

The metabolic syndrome (MetS) is an adverse metabolic state composed of obesity, hyperglycemia/pre-diabetes, hypertension, and dyslipidemia. It substantially increases the risk of type 2 diabetes, cardiovascular disease (CVD) and mortality, and has a huge impact on public health.

AREA COVERED

The present review gives an update on the definition and prevalence of MetS, and its impact on cardiac structure and function as well as on the brain and central arteries. The association with CVD and mortality risk is discussed. Focus is mainly directed toward the subclinical target organ damage related to MetS. Data is also critically reviewed to provide evidence on the incremental prognostic value of overall MetS over its individual components.

EXPERT COMMENTARY

MetS is a clinical risk condition associated with subclinical and clinical CVD and mortality. Roughly, 30% of the world population suffer from MetS. As all components of the MetS are modifiable, optimal preventive and therapeutic measures should be initiated to improve CV risk control, particularly aggressively treating hypertension and hyperglycemia, and encouraging people to adopt healthy lifestyle as early as possible is of great importance.

Renin Angiotensin System Inhibitors Reduce Aortic Stiffness and Flow Reversal After a Cryptogenic Stroke

BACKGROUND

Blood flow reversal is a possible mechanism for retrograde embolism in the setting of high-risk atherosclerotic plaques in the descending aorta (DAo). Evidence suggests that pulse wave velocity (PWV) is a determinant of blood flow reversal and can be reduced by the destiffening effect of renin-angiotensin system inhibitors (RASI).

PURPOSE

To evaluate the impact of antihypertensive therapy on in vivo changes in PWV and flow reversal in patients with cryptogenic stroke.

STUDY TYPE

Prospective.

POPULATION

Sixteen patients (69 ± 9 years; 10 males) included after cryptogenic stroke.

FIELD STRENGTH/SEQUENCE

3T. 4D flow sequence (temporal resolution = 19.6 msec) ASSESSMENT: Patients underwent aortic MRI at baseline and at 6-month follow-up. Patients received standard-of-care antihypertensive therapy that were classified as RASI vs. non-RASI medications (ie, destiffening vs. nondestiffening).We compared aortic PWV, flow reversal fraction (FRF), aortic measurements, cardiac function, and other aortic and cardiac measurements in the antihypertensive therapy groups.

STATISTICAL TESTS

Two-tailed paired or unpaired Student's t-tests (normal distributions) or Wilcoxon tests (nonnormal distribution). Univariate correlations using Pearson correlation coefficients.

RESULTS

There was a significant decrease in PWV in the RASI (n = 10) group (9.4 ± 1.6 m/s vs. 8.3 ± 1.9 m/s; P < 0.05), as well as FRF (18.6% ± 4.1% vs. 16.3% ± 4.0%; P < 0.05) between baseline and the 6-month MRI studies. There were no changes in PWV or FRF in the non-RASI (n = 6) group (P = 0.146 and P = 0.32). A decrease in FRF was significantly correlated with a decrease in PWV (r = 0.53; P < 0.05).

DATA CONCLUSION

The findings of our study suggest that RASI therapy after cryptogenic stroke resulted in a decrease of blood flow reversal and aortic stiffness.

EVIDENCE LEVEL

1 TECHNICAL EFFICACY STAGE: 4.

State of the Art Review: Brachial-Ankle PWV

The brachial-ankle pulse wave velocity (brachial-ankle PWV), which is measured simply by wrapping pressure cuffs around the four extremities, is a simple marker to assess the stiffness of the medium- to large- sized arteries. The accuracy and reproducibility of its measurement have been confirmed to be acceptable. Risk factors for cardiovascular disease, especially advanced age and high blood pressure, are reported to be associated with an increase of the arterial stiffness. Furthermore, arterial stiffness might be involved in a vicious cycle with the development/progression of hypertension, diabetes mellitus and chronic kidney disease. Increase in the arterial stiffness is thought to contribute to the development of cardiovascular disease via pathophysiological abnormalities induced in the heart, brain, kidney, and also the arteries themselves. A recent independent participant data meta-analysis conducted in Japan demonstrated that the brachial-ankle PWV is a useful marker to predict future cardiovascular events in Japanese subjects without a previous history of cardiovascular disease, independent of the conventional model for the risk assessment. The cutoff point may be 16.0 m/s in individuals with a low risk of cardiovascular disease (CVD), and 18.0 m/s in individuals with a high risk of CVD and subjects with hypertension. In addition, the method of measurement of the brachial-ankle PWV can also be used to calculate the inter-arm systolic blood pressure difference and ankle-brachial pressure index, which are also useful markers for cardiovascular risk assessment.

Arterial Stiffness in Hypertension and Function of Large Arteries

BACKGROUND

Arterial stiffness-typically assessed from non-invasive measurement of pulse wave velocity along a straight portion of the vascular tree between the right common carotid and femoral arteries-is a reliable predictor of cardiovascular risk in patients with essential hypertension.

METHODS

We reviewed how carotid-femoral pulse wave velocity increases with age and is significantly higher in hypertension (than in age- and gender-matched individuals without hypertension), particularly when hypertension is associated with diabetes mellitus.

RESULTS

From the elastic aorta to the muscular peripheral arteries of young healthy individuals, there is a gradual but significant increase in stiffness, with a specific gradient. This moderates the transmission of pulsatile pressure towards the periphery, thus protecting the microcirculatory network. The heterogeneity of stiffness between the elastic and muscular arteries causes the gradient to disappear or be inversed with aging, particularly in long-standing hypertension.

CONCLUSIONS

In hypertension therefore, pulsatile pressure transmission to the microcirculation is augmented, increasing the potential risk of damage to the brain, the heart, and the kidney. Furthermore, elevated pulse pressure exacerbates end-stage renal disease, particularly in older hypertensive individuals. With increasing age, the elastin content of vessel walls declines throughout the arterial network, and arterial stiffening increases further due to the presence of rigid wall material such as collagen, but also fibronectin, proteoglycans, and vascular calcification. Certain genes, mainly related to angiotensin and/or aldosterone, affect this aging process and contribute to the extent of arterial stiffness, which can independently affect both forward and reflected pressure waves.

Aortic stiffness is not only associated with structural but also functional parameters of retinal microcirculation

OBJECTIVE

The aim of the study was to test the hypothesis that alterations in large arteries are associated with microvascular remodelling and decreased retinal capillary blood flow.

METHODS

The study group comprised of 88 patients with essential hypertension and 32 healthy controls. Retinal microcirculation was evaluated by scanning laser Doppler flowmetry. Macrovascular changes were assessed on the basis of arterial stiffness measurement (carotid-femoral pulse wave velocity), its hemodynamic consequences (central pulse pressure, augmentation pressure, augmentation index) and intima media thickness of common carotid artery.

RESULTS

Pulse wave velocity was inversely correlated to mean retinal capillary blood flow in hypertensive patients (R = -0.32, p < 0.01). This relationship remained significant in multivariate regression analysis after adjustment for age, sex, central systolic blood pressure (BP) and body mass index (β = -31.27, p < 0.001). Lumen diameter (LD) of retinal arterioles was significantly smaller in hypertensive then normotensive subjects (79.4 vs. 83.8, p = 0.03). Central and brachial systolic, diastolic and mean BPs were significantly correlated with LD and outer diameter of retinal arterioles. The relationship between LD and central BPs remained significant in multivariate analysis (β = -0.15, p = 0.03 for cSBP; β = -0.22, p = 0.04 for cDBP; β = -0.21, p = 0.03 for cMBP). Moreover, in a subgroup with cardiac damage central and brachial pulse pressure were positively associated with retinal wall thickness, wall cross sectional area, and wall to lumen ratio.

CONCLUSION

In conclusion, the study provides a strong evidence that microcirculation is coupled with macrocirculation not only in terms of structural but also functional parameters.

Impact of Stiffer Arteries on the Response to Antihypertensive Treatment: A Longitudinal Study of the SardiNIA Cohort

OBJECTIVES

Carotid-femoral pulse wave velocity (PWV), an index of arterial stiffness and a proxy of arterial aging, has been reported to be an independent determinant of cardiovascular health. Whether the effects of antihypertensive treatment vary in the presence of accelerated arterial aging (stiffer artery, ie, PWV >10 m/s) has not been established. We tested this hypothesis in a longitudinal study in a large community-dwelling population.

DESIGN

Longitudinal population study with repeated measures.

SETTING AND PARTICIPANTS

Study population consisted of a cohort of 6011 volunteers (2546 men and 3465 women, age range 14-101 years; 15,011 observations over a median follow-up of 6.8 years) participating in the SardiNIA Study.

MEASURES

Repeated measures of PWV, blood pressure (BP), and metabolic risk factors and the antihypertensive medication trajectories of BP and PWV over time were assessed via mixed effects models.

RESULTS

Antihypertensive treatment significantly affected the trajectory of BP in both participants with (-0.47 ± 0.20 mmHg/y, P = .02) and participants without stiffer arteries (-0.47 ± 0.07 mmHg/y, P = .001). They also affected the trajectory of PWV in participants with stiffer artery, independent of the BP values.

CONCLUSIONS AND IMPLICATIONS

Antihypertensive treatment is effective in reducing both BP and PWV in older individuals with stiffer arteries.

Österreichischer Blutdruckkonsens 2019

Erhöhter Blutdruck bleibt eine Hauptursache von kardiovaskulären Erkrankungen, Behinderung und frühzeitiger Sterblichkeit in Österreich, wobei die Raten an Diagnose, Behandlung und Kontrolle auch in rezenten Studien suboptimal sind. Das Management von Bluthochdruck ist eine häufige Herausforderung für Ärztinnen und Ärzte vieler Fachrichtungen. In einem Versuch, diagnostische und therapeutische Strategien zu standardisieren und letztendlich die Rate an gut kontrollierten Hypertoniker/innen zu erhöhen und dadurch kardiovaskuläre Erkrankungen zu verhindern, haben 13 österreichische medizinische Fachgesellschaften die vorhandene Evidenz zur Prävention, Diagnose, Abklärung, Therapie und Konsequenzen erhöhten Blutdrucks gesichtet. Das hier vorgestellte Ergebnis ist der erste Österreichische Blutdruckkonsens. Die Autoren und die beteiligten Fachgesellschaften sind davon überzeugt, daß es einer gemeinsamen nationalen Anstrengung bedarf, die Blutdruck-assoziierte Morbidität und Mortalität in unserem Land zu verringern.

The place of ARBs in heart failure therapy: is aldosterone suppression the key?

Since the launch of the first orally available angiotensin II (AngII) type 1 receptor (AT₁R) blocker (ARB) losartan (Cozaar) in the late 1990s, the class of ARBs (or ‘sartans’, short for Angiotensin-RecepTor-ANtagonistS) quickly expanded to include candesartan, eprosartan, irbesartan, valsartan, telmisartan, and olmesartan. All ARBs have high affinity for the AT₁ receptor, expressed in various tissues, including smooth muscle cells, heart, kidney, and brain. Since activation of AT₁R, the target of these drugs, leads, among other effects, to vascular smooth muscle cell growth, proliferation and contraction, activation of fibroblasts, cardiac hypertrophy, aldosterone secretion from the adrenal cortex, thirst-fluid intake (hypervolemia), etc., the ARBs are nowadays one of the most useful cardiovascular drug classes used in clinical practice. However, significant differences in their pharmacological and clinical properties exist that may favor use of particular agents over others within the class, and, in fact, two of these drugs, candesartan and valsartan, continuously appear to distinguish themselves from the rest of the ‘pack’ in recent clinical trials. The reason(s) for the potential superiority of these two agents within the ARB class are currently unclear but under intense investigation. The present short review gives an overview of the clinical properties of the ARBs currently approved by the United States Food and Drug Administration, with a particular focus on candesartan and valsartan and the areas where these two drugs seem to have a therapeutic edge. In the second part of our review, we outline recent data from our laboratory (mainly) on the molecular effects of the ARB drugs on aldosterone production and on circulating aldosterone levels, which may underlie (at least in part) the apparent clinical superiority of candesartan (and valsartan) over most other ARBs currently in clinical use.

Randomized clinical trials with run-in periods: frequency, characteristics and reporting

Background

Run-in periods are occasionally used in randomized clinical trials to exclude patients after inclusion, but before randomization. In theory, run-in periods increase the probability of detecting a potential treatment effect, at the cost of possibly affecting external and internal validity. Adequate reporting of exclusions during the run-in period is a prerequisite for judging the risk of compromised validity. Our study aims were to assess the proportion of randomized clinical trials with run-in periods, to characterize such trials and the types of run-in periods and to assess their reporting.

Materials and methods

This was an observational study of 470 PubMed-indexed randomized controlled trial publications from 2014. We compared trials with and without run-in periods, described the types of run-in periods and evaluated the completeness of their reporting by noting whether publications stated the number of excluded patients, reasons for exclusion and baseline characteristics of the excluded patients.

Results

Twenty-five trials reported a run-in period (5%). These were larger than other trials (median number of randomized patients 217 vs 90, P=0.01) and more commonly industry trials (11% vs 3%, P<0.01). The run-in procedures varied in design and purpose. In 23 out of 25 trials (88%), the run-in period was incompletely reported, mostly due to missing baseline characteristics.

Conclusion

Approximately 1 in 20 trials used run-in periods, though much more frequently in industry trials. Reporting of the run-in period was often incomplete, precluding a meaningful assessment of the impact of the run-in period on the validity of trial results. We suggest that current trials with run-in periods are interpreted with caution and that updates of reporting guidelines for randomized trials address the issue.

2018 ESC/ESH Guidelines for the management of arterial hypertension: The Task Force for the management of arterial hypertension of the European Society of Cardiology and the European Society of Hypertension: The Task Force for the management of arterial hypertension of the European Society of Cardiology and the European Society of Hypertension

: Document reviewers: Guy De Backer (ESC Review Co-ordinator) (Belgium), Anthony M. Heagerty (ESH Review Co-ordinator) (UK), Stefan Agewall (Norway), Murielle Bochud (Switzerland), Claudio Borghi (Italy), Pierre Boutouyrie (France), Jana Brguljan (Slovenia), Héctor Bueno (Spain), Enrico G. Caiani (Italy), Bo Carlberg (Sweden), Neil Chapman (UK), Renata Cifkova (Czech Republic), John G. F. Cleland (UK), Jean-Philippe Collet (France), Ioan Mircea Coman (Romania), Peter W. de Leeuw (The Netherlands), Victoria Delgado (The Netherlands), Paul Dendale (Belgium), Hans-Christoph Diener (Germany), Maria Dorobantu (Romania), Robert Fagard (Belgium), Csaba Farsang (Hungary), Marc Ferrini (France), Ian M. Graham (Ireland), Guido Grassi (Italy), Hermann Haller (Germany), F. D. Richard Hobbs (UK), Bojan Jelakovic (Croatia), Catriona Jennings (UK), Hugo A. Katus (Germany), Abraham A. Kroon (The Netherlands), Christophe Leclercq (France), Dragan Lovic (Serbia), Empar Lurbe (Spain), Athanasios J. Manolis (Greece), Theresa A. McDonagh (UK), Franz Messerli (Switzerland), Maria Lorenza Muiesan (Italy), Uwe Nixdorff (Germany), Michael Hecht Olsen (Denmark), Gianfranco Parati (Italy), Joep Perk (Sweden), Massimo Francesco Piepoli (Italy), Jorge Polonia (Portugal), Piotr Ponikowski (Poland), Dimitrios J. Richter (Greece), Stefano F. Rimoldi (Switzerland), Marco Roffi (Switzerland), Naveed Sattar (UK), Petar M. Seferovic (Serbia), Iain A. Simpson (UK), Miguel Sousa-Uva (Portugal), Alice V. Stanton (Ireland), Philippe van de Borne (Belgium), Panos Vardas (Greece), Massimo Volpe (Italy), Sven Wassmann (Germany), Stephan Windecker (Switzerland), Jose Luis Zamorano (Spain).The disclosure forms of all experts involved in the development of these Guidelines are available on the ESC website www.escardio.org/guidelines.

Arterial stiffness in elderly patients with normotension and hypertension in Brazil

Data on arterial stiffness in older populations, according to blood pressure (BP) levels, are scarce in Brazil. The objective of this study was to establish reference values for core measures of arterial stiffness, including carotid-femoral pulse wave velocity (cf-PWV) and aortic augmentation index (AIx), in a cohort of older individuals with normotension (NT) and hypertension. Cross-sectional analysis was performed with applanation tonometry data from 1192 patients aged 60 years or older. The authors classified patients according to their BP levels as having NT, controlled hypertension (CH), and uncontrolled hypertension (UH). The cf-PWV values were 9.11 ± 0.16 m/s (NT), 9.12 ± 0.18 m/s (CH), and 9.42 ± 2.2 m/s (UH) (P < 0.005; UH vs NT and CH). The AIx was 33.3% for the entire cohort and similar across all groups. The cf-PWV increased with age but reached a ceiling at 75 years. Compared with men, women had a higher AIx but similar cf-PWV levels. In conclusion, the markers of arterial stiffness were similar among individuals with NT/CH and higher among individuals with UH.

Arterial (Aortic) Stiffness in Patients with Resistant Hypertension: from Assessment to Treatment

PURPOSE OF REVIEW

The purpose of the review is to examine whether measurement of aortic stiffness could be especially value-adding for risk stratification and treatment among patients with resistant hypertension (RH).

RECENT FINDINGS

Adverse arterial remodeling and increased aortic stiffness is associated with RH, and it may be of additional clinical benefit to measure aortic stiffness in these patients. However, there is insufficient evidence to determine whether aortic stiffness is excessively high relative to the level of blood pressure (BP) among people with RH. This issue needs resolution as it could help refine management decisions guided by aortic stiffness. If conventional antihypertensive therapy fails to lower BP in patients with RH, there is good rationale for effectiveness of spironolactone as add on therapy, and this should also improve aortic stiffness. Lifestyle intervention with exercise and diet should be additionally efficacious towards improving BP and aortic stiffness in patients with RH, but there is limited data in this patient population. For better characterization on the effects of BP treatment on aortic stiffness, measures of central aortic BP may help refine management decisions above and beyond conventional arm cuff BP. There is strong evidence to support the use of aortic stiffness as a tool to aid risk stratification in hypertension management. Although there is a theoretical basis for special additional benefit of measuring aortic stiffness in patients with RH (as distinct from uncomplicated hypertension), at this time, there is inadequate data available to make definitive conclusions and is an area for future investigation.

Influence of vascular geometry on local hemodynamic parameters: phantom and small rodent study

BACKGROUND

Many studies have demonstrated that the geometry of the carotid bifurcation enables prediction of blood flow variation associated with atherosclerotic plaque formation. The phase angle between the arterial wall circumferential strain and its instantaneous wall shear stress is known as stress phase angle (SPA). This parameter is used to evaluate hemodynamic factors of atherogenesis. Note that SPA can be numerically computed for the purpose of locating atherosclerosis in different artery geometries. However, there is no experimental data to verify its role in the location of atherosclerosis in different artery geometries. In this study, we use an ultrasonic biomechanical method to experimentally evaluate the role of SPA for locating atherosclerosis in carotid bifurcation.

RESULTS

For carotid anthropomorphic vascular phantom experiments, the SPAs of common carotid arteries (CCAs), external carotid arteries (ECAs) and internal carotid arteries (ICAs) are - 148.53 ± 6.92°, - 153.95 ± 5.11°, and - 238.69 ± 1.72°, respectively. The corresponding SPAs are - 173.47 ± 0.065°, - 115.57 ± 4.83° and - 233.9 ± 8.12° for the polyvinyl alcohol (PVA-c) phantoms. In vivo mouse experiments indicated that the wall shear stress and circumferential strain were out of phase in the ICAs (- 280.08 ± 13.12°) to a greater extent as compared to CCAs (- 141.97 ± 8.03°) and ECAs (- 170.07 ± 9.24°).

CONCLUSIONS

The results suggested that SPA may be a useful indicator to locate the atherosclerosis position in carotid bifurcation.

Pulse Pressure Is Associated With Early Brain Atrophy and Cognitive Decline: Modifying Effects of APOE-ε4

We investigated whether midlife pulse pressure is associated with brain atrophy and cognitive decline, and whether the association was modified by apolipoprotein-E ε4 (APOE-ε4) and hypertension. Participants (549 stroke-free and dementia-free Framingham Offspring Cohort Study participants, age range=55.0 to 64.9 y) underwent baseline neuropsychological and magnetic resonance imaging (subset, n=454) evaluations with 5- to 7-year follow-up. Regression analyses investigated associations between baseline pulse pressure (systolic-diastolic pressure) and cognition, total cerebral volume and temporal horn ventricular volume (as an index of smaller hippocampal volume) at follow-up, and longitudinal change in these measures. Interactions with APOE-ε4 and hypertension were assessed. Covariates included age, sex, education, assessment interval, and interim stroke. In the total sample, baseline pulse pressure was associated with worse executive ability, lower total cerebral volume, and greater temporal horn ventricular volume 5 to 7 years later, and longitudinal decline in executive ability and increase in temporal horn ventricular volume. Among APOE-ε4 carriers only, baseline pulse pressure was associated with longitudinal decline in visuospatial organization. Findings indicate arterial stiffening, indexed by pulse pressure, may play a role in early cognitive decline and brain atrophy in mid to late life, particularly among APOE-ε4 carriers.

Personalised Single-Pill Combination Therapy in Hypertensive Patients: An Update of a Practical Treatment Platform

Despite the improvements in the management of hypertension during the last three decades, it continues to be one of the leading causes of cardiovascular morbidity and mortality worldwide. Effective and sustained reductions in blood pressure (BP) reduce the incidence of myocardial infarction, stroke, congestive heart failure and cardiovascular death. However, the proportion of patients who achieve the recommended BP goal (< 140/90 mmHg) is persistently low, worldwide. Poor adherence to therapy, complex therapeutic regimens, clinical inertia, drug-related adverse events and multiple risk factors or comorbidities contribute to the disparity between the potential and actual BP control rate. Previously we published a practical therapeutic platform for the treatment of hypertension based on clinical evidence, guidelines, best practice and clinical experience. This platform provides a personalised treatment approach and can be used to improve BP control and simplify treatment. It uses long-acting, effective and well-tolerated angiotensin receptor blocker (ARB) olmesartan, in combination with a calcium channel blocker amlodipine, and/or a thiazide diuretic hydrochlorothiazide. These drugs were selected based on the availability in most European Countries of single-pill, fixed formulations in a wide range of doses for both dual- and triple-drug combinations. The platform approach could be applied to other ARBs or angiotensin-converting enzyme inhibitors available in single-pill, fixed-dose combinations. Here, we present an update, which takes into account the results of the recently published studies and extends the applicability of the platform to common conditions that are often neglected or poorly considered in clinical practice guidelines.

Vascular Smooth Muscle Cells and Arterial Stiffening: Relevance in Development, Aging, and Disease

The cushioning function of large arteries encompasses distension during systole and recoil during diastole which transforms pulsatile flow into a steady flow in the microcirculation. Arterial stiffness, the inverse of distensibility, has been implicated in various etiologies of chronic common and monogenic cardiovascular diseases and is a major cause of morbidity and mortality globally. The first components that contribute to arterial stiffening are extracellular matrix (ECM) proteins that support the mechanical load, while the second important components are vascular smooth muscle cells (VSMCs), which not only regulate actomyosin interactions for contraction but mediate also mechanotransduction in cell-ECM homeostasis. Eventually, VSMC plasticity and signaling in both conductance and resistance arteries are highly relevant to the physiology of normal and early vascular aging. This review summarizes current concepts of central pressure and tensile pulsatile circumferential stress as key mechanical determinants of arterial wall remodeling, cell-ECM interactions depending mainly on the architecture of cytoskeletal proteins and focal adhesion, the large/small arteries cross-talk that gives rise to target organ damage, and inflammatory pathways leading to calcification or atherosclerosis. We further speculate on the contribution of cellular stiffness along the arterial tree to vascular wall stiffness. In addition, this review provides the latest advances in the identification of gene variants affecting arterial stiffening. Now that important hemodynamic and molecular mechanisms of arterial stiffness have been elucidated, and the complex interplay between ECM, cells, and sensors identified, further research should study their potential to halt or to reverse the development of arterial stiffness.

Lysyl Oxidase Induces Vascular Oxidative Stress and Contributes to Arterial Stiffness and Abnormal Elastin Structure in Hypertension: Role of p38MAPK

AIMS

Vascular stiffness, structural elastin abnormalities, and increased oxidative stress are hallmarks of hypertension. Lysyl oxidase (LOX) is an elastin crosslinking enzyme that produces H2O2 as a by-product. We addressed the interplay between LOX, oxidative stress, vessel stiffness, and elastin.

RESULTS

Angiotensin II (Ang II)-infused hypertensive mice and spontaneously hypertensive rats (SHR) showed increased vascular LOX expression and stiffness and an abnormal elastin structure. Mice over-expressing LOX in vascular smooth muscle cells (TgLOX) exhibited similar mechanical and elastin alterations to those of hypertensive models. LOX inhibition with β-aminopropionitrile (BAPN) attenuated mechanical and elastin alterations in TgLOX mice, Ang II-infused mice, and SHR. Arteries from TgLOX mice, Ang II-infused mice, and/or SHR exhibited increased vascular H2O2 and O2.- levels, NADPH oxidase activity, and/or mitochondrial dysfunction. BAPN prevented the higher oxidative stress in hypertensive models. Treatment of TgLOX and Ang II-infused mice and SHR with the mitochondrial-targeted superoxide dismutase mimetic mito-TEMPO, the antioxidant apocynin, or the H2O2 scavenger polyethylene glycol-conjugated catalase (PEG-catalase) reduced oxidative stress, vascular stiffness, and elastin alterations. Vascular p38 mitogen-activated protein kinase (p38MAPK) activation was increased in Ang II-infused and TgLOX mice and this effect was prevented by BAPN, mito-TEMPO, or PEG-catalase. SB203580, the p38MAPK inhibitor, normalized vessel stiffness and elastin structure in TgLOX mice.

INNOVATION

We identify LOX as a novel source of vascular reactive oxygen species and a new pathway involved in vascular stiffness and elastin remodeling in hypertension.

CONCLUSION

LOX up-regulation is associated with enhanced oxidative stress that promotes p38MAPK activation, elastin structural alterations, and vascular stiffness. This pathway contributes to vascular abnormalities in hypertension. Antioxid. Redox Signal. 27, 379-397.

Antihypertensive drugs

Successful treatment of hypertension is possible with limited side effects given the availability of multiple antihypertensive drug classes. This review describes the various pharmacological classes of antihypertensive drugs, under two major aspects: their mechanisms of action and side effects. The mechanism of action is analysed through a pharmacological approach, i.e. the molecular receptor targets, the various sites along the arterial system, and the extra-arterial sites of action, in order to better understand in which type of hypertension a given pharmacological class of antihypertensive drug is most indicated. In addition, side effects are described and explained through their pharmacological mechanisms, in order to better understand their mechanism of occurrence and in which patients drugs are contra-indicated. This review does not address the effectiveness of monotherapies in large randomized clinical trials and combination therapies, since these are the matters of other articles of the present issue. Five major pharmacological classes of antihypertensive drugs are detailed here: beta-blockers, diuretics, angiotensin converting enzyme inhibitors, angiotensin II receptor antagonists, and calcium channel blockers. Four additional pharmacological classes are described in a shorter manner: renin inhibitors, alpha-adrenergic receptor blockers, centrally acting agents, and direct acting vasodilators.

Arterial Destiffening in Previously Untreated Mild Hypertensives After 1 Year of Routine Clinical Management

BACKGROUND

Arterial stiffness, measured with pulse wave velocity (PWV), is now classified as a marker of target organ damage (TOD) alongside left ventricular hypertrophy and moderately increased albuminuria. Interventional studies on treated hypertensive patients have shown that PWV could be improved. Our aim was to assess changes in arterial stiffness after 1 year of routine clinical practice in never-treated hypertensive patients.

PATIENTS AND METHODS

We studied 356 never-treated patients with suspected hypertension. After standard clinical assessment during which presence of TOD was evaluated, hypertension diagnosis was confirmed in 231 subjects who subsequently received standard routine care. Both hypertensive and the 125 controls came back for a follow-up visit after 1 year.

RESULTS

Hypertensive patients were slightly older (46 ± 12 vs. 50 ± 12 years, P < 0.001), with higher mean arterial pressure (MAP)-adjusted PWV compared to controls (8.6 ± 2.0 vs. 8.0 ± 1.7 m/s, P < 0.001) and 47% of them presented 1 or more TOD. After 1 year of treatment, MAP was similar in both groups (94.9 vs. 96.2 mm Hg; P = ns), but adjusted PWV remained significantly higher in the hypertensive patients (7.8 ± 1.4 vs. 8.3 ± 1.7 m/s, P = 0.004). The prevalence of elevated PWV was reduced from 20% to 12%. All antihypertensive drugs achieved the same blood pressure (BP) and PWV reduction with the exception of vasodilating beta-blockers which gave slightly better results probably due to heart rate reduction.

CONCLUSION

BP reduction in newly diagnosed hypertensive patients improves arterial stiffness within a year of real-life clinical practice. Patients with the highest PWV and the largest reduction of BP "destiffened" the most whatever antihypertensive class was used.