Destiffening effect of valsartan and atenolol: influence of heart rate and blood pressure

Brachial-ankle pulse wave velocity increasing with heart rate accelerates

Pulse wave velocity (PWV) indicates the degree of vascular stiffness. This study aimed to explore the association between heart rate (HR) and brachial-ankle (ba)-PWV in patients with pacemaker implantation. This retrospective observational study included patients who underwent permanent pacemaker implantation at the Second Hospital of Hebei Medical University between December 2018 and December 2021. All patients were pacemaker-dependent, and the ba-PWV values were collected during HR setted from 60 to 100 bpm. A total of 68 patients (34 males, aged 65.97 ± 9.90 years) were included in this study. There were significant difference of ba-PWV and diastolic blood pressure (DBP) among different HR (both P < 0.001). After adjusted systolic blood pressure (SBP), DBP, age, and sex, the generalized estimating equation showed ba-PWV was independently associated with HR, with increased HR showed higher coefficient: 70 bpm: β = 42.26 (95% CI: 15.34-69.18, P = 0.002), 80 bpm: β = 84.16 (95% CI: 52.48-115.84, P < 0.001), 90 bpm: β = 129.27 (95% CI: 52.48-115.84, P < 0.001), and 100 bpm: 186.31 (95% CI: 137.02-235.59, P < 0.001). The results demonstrate that changes in HR may affect the ba-PWV, the ba-PWV values tend to be higher when HR accelerates.

Vascular Aging: Assessment and Intervention

Vascular aging represents a collection of structural and functional changes in a blood vessel with advancing age, including increased stiffness, vascular wall remodeling, loss of angiogenic ability, and endothelium-dependent vasodilation dysfunction. These age-related alterations may occur earlier in those who are at risk for or have cardiovascular diseases, therefore, are defined as early or premature vascular aging. Vascular aging contributes independently to cardio-cerebral vascular diseases (CCVDs). Thus, early diagnosis and interventions targeting vascular aging are of paramount importance in the delay or prevention of CCVDs. Here, we review the direct assessment of vascular aging by examining parameters that reflect changes in structure, function, or their compliance with age including arterial wall thickness and lumen diameter, endothelium-dependent vasodilation, arterial stiffness as well as indirect assessment through pathological studies of biomarkers including endothelial progenitor cell, lymphocytic telomeres, advanced glycation end-products, and C-reactive protein. Further, we evaluate how different types of interventions including lifestyle mediation, such as caloric restriction and salt intake, and treatments for hypertension, diabetes, and hyperlipidemia affect age-related vascular changes. As a single parameter or intervention targets only a certain vascular physiological change, it is recommended to use multiple parameters to evaluate and design intervention approaches accordingly to prevent systemic vascular aging in clinical practices or population-based studies.

Prediction of CKD Progression and Cardiovascular Events Using Albuminuria and Pulse Wave Velocity

INTRODUCTION

Chronic kidney disease (CKD) is associated with cardiovascular disease (CVD) and death. Albuminuria is an established risk factor, but additional biomarkers predicting CKD progression or CVD are needed. Arterial stiffness is an easily measurable parameter that has been associated with CVD and mortality. We evaluated the ability of carotid-femoral pulse wave velocity (PWV) and urine albumin-creatinine (UAC) ratio to predict CKD progression, cardiovascular events, and mortality in a cohort of CKD patients.

METHODS

In CKD stage 3-5 patients, PWV and UAC were measured at baseline. CKD progression was defined as 50% decline in estimated glomerular filtration rate (eGFR), initiation of dialysis, or renal transplantation. A composite endpoint was defined as CKD progression, myocardial infarction, stroke, or death. Endpoints were analyzed using Cox regression analysis adjusted for possible confounders.

RESULTS

We included 181 patients (median age 69 [interquartile range 60-75] years, 67% males) with a mean eGFR of 37 ± 12 mL/min/1.73 m2 and UAC 52 (5-472) mg/g. Mean PWV was 10.6 m/s. Median follow-up until first event was 4 (3-6) years with 44 and 89 patients reaching a CKD progression or composite endpoint, respectively. UAC (g/g) significantly predicted both CKD progression (HR 1.5 [1.2; 1.8]) and composite endpoints (HR 1.4 [1.1; 1.7]) in adjusted Cox regression. In contrast, PWV (m/s) was not associated with neither CKD progression (HR 0.99 [0.84; 1.18]) nor the composite endpoint (HR 1.03 [0.92; 1.15]).

CONCLUSION

In an aging CKD population, UAC predicted both CKD progression and a composite endpoint of CKD progression, cardiovascular events, or death, while PWV did not.

Adaptation of Arterial Wall Viscosity to the Short-Term Reduction of Heart Rate: Impact of Aging

Background Changes in arterial wall viscosity, which dissipates the energy stored within the arterial wall, may contribute to the beneficial effect of heart rate (HR) reduction on arterial stiffness and cardiovascular coupling. However, it has never been assessed in humans and could be altered by aging. We evaluated the effect of a selective HR-lowering agent on carotid arterial wall viscosity and the impact of aging on this effect. Methods and Results This randomized, placebo-controlled, double-blind, crossover study performed in 19 healthy volunteers evaluated the effects of ivabradine (5 mg BID, 1-week) on carotid arterial wall viscosity, mechanics, hemodynamics, and cardiovascular coupling. Arterial wall viscosity was evaluated by the area of the hysteresis loop of the pressure-lumen cross-sectional area relationship, representing the energy dissipated (W_V), and by the relative viscosity (W_V/W_E), with W_E representing the elastic energy stored. HR reduction by ivabradine increased W_V and W_E whereas W_V/W_E remained stable. In middle-aged subjects (n=11), baseline arterial stiffness and cardiovascular coupling were less favorable, and W_E was similar but W_V and therefore W_V/W_E were lower than in youth (n=8). HR reduction increased W_V/W_E in middle-aged but not in young subjects, owing to a larger increase in W_V than W_E. These results were supported by the age-related linear increase in W_V/W_E after HR reduction (P=0.009), explained by a linear increase in W_V. Conclusion HR reduction increases arterial wall energy dissipation proportionally to the increase in W_E, suggesting an adaptive process to bradycardia. This mechanism is altered during aging resulting in a larger than expected energy dissipation, the impact of which should be assessed. Registration URL: https://www.clinicaltrials.gov; Unique identifier: 2015/077/HP. URL: https://www. eudract.ema.europa.eu; Unique identifier: 2015-002060-17.

Effects of enhanced versus reduced vasodilating treatment on brachial and central blood pressure in patients with chronic kidney disease: a randomized controlled trial

BACKGROUND

Blood pressure (BP) control is important in chronic kidney disease (CKD), but a reduction in brachial BP may not mirror changes in central aortic BP (cBP) during antihypertensive medication. We hypothesize that a fall in cBP is better reflected during enhanced vasodilation treatment (EVT) compared with reduced vasodilation treatment (RVT) because of different hemodynamic actions of these interventions.

METHODS

Eighty-one hypertensive CKD stage 3-4 patients (mean measured glomerular filtration rate 36 ml/min per 1.73 m2) were randomized to either EVT based on renin--angiotensin blockade and/or amlodipine or RVT based on nonvasodilating β-blockade (metoprolol). Before randomization and following 18 months of treatment, we performed 24-h ambulatory BP measurements (ABPM) and radial artery pulse wave analysis for estimation of cBP and augmentation index (AIx). Forearm resistance (Rrest) was determined by venous occlusion plethysmography and arterial stiffness by carotid--femoral pulse wave velocity (PWV). Matched healthy controls were studied once for comparison.

RESULTS

Compared with controls, CKD patients had elevated ABPM, cBP and PWV. Although ABPM remained unchanged from baseline to follow-up in both treatment groups, cBP decreased 4.7/2.9 mmHg (systolic/diastolic) during EVT and increased 5.1/1.5 mmHg during RVT (Δ=9.8/4.4 mmHg, P=0.02 for SBP, P = 0.05 for DBP). At follow-up, the difference between systolic cBP and 24-h ABPM (ΔBPsyst) was negatively associated with heart rate and positively associated with AIx and Rrest (all P < 0.01) but not PWV (P = 0.32).

CONCLUSION

In CKD patients, EVT and RVT have opposite effects on cBP and the difference between cBP and ambulatory BP is larger for EVT than RVT.

Treatment effect of lacidipine and amlodipine on clinic and ambulatory blood pressure and arteria stiffness in a randomised double-blind trial

PURPOSE

In a randomised, double-blind trial, we investigated effects of lacidipine on clinic and ambulatory blood pressure (BP) and arterial stiffness in patients with mild-to-moderate hypertension, as compared with amlodipine.

MATERIALS AND METHODS

Previously untreated and treated patients (n = 269, 50-80 years of age) with clinic hypertension (a clinic systolic/diastolic BP 140-180/<110 mmHg and <160/100 mmHg, respectively) were randomly assigned to double-dummy treatment with lacidipine (4-6 mg/day) or amlodipine (5-7.5 mg/day) for 20 weeks. The primary efficacy variable was the change in 24-h ambulatory systolic BP at 20 weeks of treatment. Arterial stiffness was measured as brachial-ankle pulse wave velocity (PWV).

RESULTS

After 20 weeks of treatment, 24-h systolic BP decreased from 141.3 ± 14.0 and 138.3 ± 12.8 mmHg at baseline, respectively, in the lacidipine (n = 134) and amlodipine groups (n = 135), by a least square mean (±SE) change of 15.2 ± 1.3 and 15.5 ± 1.3 mmHg, respectively, with a between-group difference (95% confidence interval [CI]) of 0.3 mmHg (-3.4 to 4.1, p = 0.86). Similar results were observed for other ambulatory BP components and clinic BP. Clinic and ambulatory pulse rate did not significantly change in either group (p ≥ 0.21). PWV decreased significantly (p < 0.001) from baseline in both groups, with a non-significant between-group difference of 0.24 m/s (p = 0.45). The incidence rate of adverse events was 30.3% (n = 40) and 27.5% (n = 36) in the lacidipine and amlodipine groups, respectively (p = 0.61). No serious adverse event occurred in the trial.

CONCLUSIONS

Lacidipine effectively lowers clinic and ambulatory BP in patients with mild-to-moderate hypertension and significantly improves arterial stiffness, similarly as amlodipine.

Systolic Blood Pressure and Longitudinal Progression of Arterial Stiffness: A Quantitative Meta-Analysis

Background

Arterial stiffness predicts the risk of cardiovascular events and all‐cause mortality and is associated with age and hypertension. However, the magnitude of the relationship between blood pressure (BP) and progression of arterial stiffness is unclear, limiting our understanding of how arterial stiffness mediates clinical effects of hypertension and planning of clinical trials.

Methods and Results

Medline and EMBASE were searched for prospective studies reporting linear models between baseline BP and progression of arterial stiffness, with and without adjustment for demographic characteristics and baseline stiffness. Standardized and unstandardized β coefficients for pulse wave velocity were combined by fixed and random effects meta‐analysis, weighted by the inverse variance. Of 566 fully reviewed articles from 30, 524 titles, 22 populations from 21 reports were included. In 9 cohorts, there were consistent, adjusted associations between baseline systolic BP and progression of arterial stiffness (11 781 patients; standardized β=0.041; 95% CI, 0.026–0.055; P<0.001; P value for heterogeneity=0.70), equivalent to a 1.14‐m/s increase in standard carotid‐femoral pulse wave velocity per decade per 20–mm Hg systolic BP, independent of age. Unstandardized, adjusted associations were similar (1762 patients; β=0.0047; 95% CI, 0.004–0.006; P<0.001; P value for heterogeneity=0.64), equivalent to a 0.94‐m/s increase per decade per 20–mm Hg systolic BP. In limited studies, standardized associations between mean BP and arterial stiffness progression were not significant and heterogeneous (913 patients; β=0.039; 95% CI, −0.008 to 0.086; P=0.11; P value for heterogeneity=0.03).

Conclusions

Baseline systolic BP was associated with a clinically important progression of arterial stiffness, independent of age, providing a reference for the potential effect of arterial stiffness in mediating changes in clinical outcomes associated with hypertension and providing a reference value to aid clinical trial design.

Maladaptive aortic remodeling in hypertension associates with dysfunctional smooth muscle contractility

Intramural cells are responsible for establishing, maintaining, and restoring the functional capability and structural integrity of the aortic wall. In response to hypertensive loading, these cells tend to increase wall content via extracellular matrix turnover in an attempt to return wall stress and/or material stiffness toward homeostatic values despite the elevated pressure. Using a common rodent model of induced hypertension, we found marked mouse-to-mouse differences in thoracic aortic remodeling over 2-4 wk of pressure elevation, with mechanoadaptation in some but gross maladaptation in most mice despite the same experimental conditions and overall genetic background. Consistent with our hypothesis, we also found a strong correlation between maladaptive aortic remodeling and a dysfunctional ability of the vessel to vasoconstrict, with maladaptation often evidenced by marked adventitial fibrosis. Remarkably, mouse-to-mouse variability did not correlate with the degree or duration of pressure elevation over the 2- to 4-wk study period. These findings suggest both a need to study together the structure, mechanical properties, and function across layers of the wall when assessing aortic health and a need for caution in using common statistical comparisons across small seemingly well-defined groups that may mask important underlying individual responses, an area of investigation that demands increasing attention as we move toward an era of precision diagnosis and patient care. NEW & NOTEWORTHY There are three primary findings. Marked mouse-to-mouse differences exist in large vessel hypertensive remodeling in an otherwise equivalent cohort of animals. The degree of maladaptation correlates strongly with decreases in smooth muscle contractile capacity. Finally, short-term maladaptive remodeling is independent of the precise degree or duration of the pressure elevation provided that thresholds are exceeded. Therapeutic targets should thus be personalized and focus on both layer-to-layer interactions and early interventions.

Efficacy and effectiveness of valsartan/amlodipine and valsartan/amlodipine/hydrochlorothiazide in hypertension: randomized controlled versus observational studies

OBJECTIVE

The aim of this post-hoc analysis was to compare the results from randomized controlled trials (RCTs) and real-world evidence (RWE) studies of valsartan/amlodipine (Val/Aml) and valsartan/amlodipine/hydrochlorothiazide (Val/Aml/HCTZ) in patients with uncontrolled hypertension (>140/90 mmHg).

METHODS

Data was pooled from 15 RCTs (N = 5542) and 8 RWE studies (N = 1397) for Val/Aml; and 2 RCTs (N = 804) and 5 RWE studies (N = 9380) for Val/Aml/HCTZ. Patients who received Val/Aml (80/5, 160/5, 160/10, 320/5, or 320/10 mg), Val/Aml/HCTZ (160/5/12.5, 160/5/25, 160/10/12.5, 160/10/25, or 320/10/25 mg) or placebo were considered for this analysis. Only patients with both baseline and follow-up assessment within 60-90 days after baseline had been included in the analysis. Patients with missing values were excluded from the analysis. Using fitted linear mixed-effects model and random factors, treatment interactions and study design with mean sitting systolic blood pressure (msSBP), diastolic BP (msDBP) and pulse pressure (msPP) reductions from baseline to Week 8-12 of treatment were compared.

RESULTS

Baseline demographics and patient characteristics were comparable between RCT and RWE datasets and within Val/Aml and Val/Aml/HCTZ treatment groups. In both RCT and RWE studies, least-squares mean (LSM) reduction in msSBP/msDBP and msPP from baseline were significant (p < .05) across all dosages. The efficacy of Val/Aml in RCTs was statistically significantly greater than in RWE studies for msSBP/msDBP (-23.1/-13.8 vs. -17.9/-9.1 mmHg) but the difference was non-significant for msPP (-8.6 vs. -9.3 mmHg; p = .77). For Val/Aml/HCTZ, no direct comparison was available but a similar trend was observed. The difference observed for msSBP and msDBP may be due to routine practice setting, larger populations may have more confounders and different behaviors towards treatment adherence.

CONCLUSION

These findings demonstrate that the efficacy of Val/Aml and Val/Aml/HCTZ in RCTs was more pronounced compared with their effectiveness in RWE studies in different ethnic populations although the overall benefit was not different.

Salbutamol-induced Decrease in Augmentation Index is Related to the Parallel Increase in Heart Rate

The change in augmentation index following salbutamol inhalation has been applied to evaluate endothelial function. We examined the contribution of salbutamol-induced increase in heart rate to the observed decrease in augmentation index. Haemodynamics were recorded using whole-body impedance cardiography and continuous pulse wave analysis from tonometric radial blood pressure. All subjects (n = 335, mean age 46, body mass index 26, 48% men) were without medications with cardiovascular influences. The effects of salbutamol inhalation (0.4 mg) versus the endothelium-independent agent nitroglycerin resoriblet (0.25 mg) were examined during passive head-up tilt, as the haemodynamic influences of these compounds depend on body position. Salbutamol decreased augmentation index by ~3-4% units in supine and upright positions. Although salbutamol moderately increased cardiac index (+4.5%) and decreased systemic vascular resistance (-8.5%), the significant haemodynamic explanatory factors for decreased augmentation index in multivariate analysis were increased supine heart rate, and increased upright heart rate and decreased ejection duration (p < 0.001 for all, r²  = 0.36-0.37). Sublingual nitroglycerin decreased supine and upright augmentation index by ~15% units and ~23% units, respectively. The haemodynamic explanatory factors for these changes in multivariate analysis were increased heart rate, reduced ejection duration and reduced systemic vascular resistance (p ≤ 0.021 for all, r²  = 0.22-0.34). In conclusion, the lowering influence of salbutamol on augmentation index may be largely explained by increased heart rate, suggesting that this effect may not predominantly reflect endothelial function.

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.

Therapeutic Modulation of Aortic Stiffness

Aortic stiffness (AS) is an important predictor of cardiovascular morbidity in humans. The present review discusses the possible pathophysiological mechanisms of AS and focuses on a survey of different therapeutic modalities for decreasing AS. The influence of several nonpharmacological interventions is described: decrease body weight, diet, aerobic exercise training, music, and continuous positive airway pressure therapy. The effects of different pharmacological drug classes on AS are also discussed: antihypertensive drugs-renin-angiotensin-aldosterone system drugs, beta-blockers, alpha-blockers, diuretics, and calcium channel blockers (CCBs)-advanced glycation end product cross-link breakers, statins, oral anti-diabetics, anti-inflammatory drugs, vitamin D, antioxidant vitamins, and endothelin-1 receptor antagonists. All of these have shown some effect in decreasing AS.

Arterial stiffness and decline of renal function in a primary care population

Arterial stiffness is an important pathophysiological factor linking cardiovascular disease and kidney disease. Controversy exists as to whether arterial stiffness causes renal function decline, or kidney dysfunction leads to stiffening or whether the association is mutual. We aimed to investigate the longitudinal association between arterial stiffness and annual rate of renal function decline. We prospectively investigated in a primary care population whether carotid-femoral pulse wave velocity (PWV) was associated with estimated glomerular filtration rate (eGFR) and annual decline in eGFR in participants aged ⩾40 years without overt kidney disease. Baseline data on PWV and eGFR were available for 587 participants; follow-up measurements with a mean duration of 5.6 years were available for 222 patients. PWV, female gender and mean arterial pressure were independently associated with eGFR at baseline, although age confounded this association. More importantly, baseline PWV, age and eGFR were independent predictors of renal function decline. Stratification for age showed that the effect of PWV on rate of eGFR decline was amplified with advancing age. On the other hand, baseline eGFR did not determine annual change in PWV, suggesting a unidirectional association between arterial stiffness and eGFR. Arterial stiffness amplifies age-related renal function decline, suggesting that arterial stiffness plays a causal role in the development of renal damage, at least at later stages of age-related renal function decline, possibly through impaired renal autoregulation and increased arterial blood pressure pulsatility.

Selective Heart Rate Reduction With Ivabradine Increases Central Blood Pressure in Stable Coronary Artery Disease

Abstract—

Heart rate (HR) lowering by β-blockade was shown to be beneficial after myocardial infarction. In contrast, HR lowering with ivabradine was found to confer no benefits in 2 prospective randomized trials in patients with coronary artery disease. We hypothesized that this inefficacy could be in part related to ivabradine’s effect on central (aortic) pressure. Our study included 46 patients with chronic stable coronary artery disease who were randomly allocated to placebo (n=23) or ivabradine (n=23) in a single-blinded fashion for 6 months. Concomitant baseline medication was continued unchanged throughout the study except for β-blockers, which were stopped during the study period. Central blood pressure and stroke volume were measured directly by left heart catheterization at baseline and after 6 months. For the determination of resting HR at baseline and at follow-up, 24-hour ECG monitoring was performed. Patients on ivabradine showed an increase of 11 mm Hg in central systolic pressure from 129±22 mm Hg to 140±26 mm Hg ( P =0.02) and in stroke volume by 86±21.8 to 107.2±30.0 mL ( P =0.002). In the placebo group, central systolic pressure and stroke volume remained unchanged. Estimates of myocardial oxygen consumption (HR×systolic pressure and time-tension index) remained unchanged with ivabradine.The decrease in HR from baseline to follow-up correlated with the concomitant increase in central systolic pressure ( r =−0.41, P =0.009) and in stroke volume ( r =−0.61, P <0.001). In conclusion, the decrease in HR with ivabradine was associated with an increase in central systolic pressure, which may have antagonized possible benefits of HR lowering in coronary artery disease patients.

Clinical Trials—URL:

http://www.clinicaltrials.gov . Unique identifier NCT01039389.

Influence of obesity in central blood pressure

BACKGROUND

Obesity is an important risk factor for cardiovascular disease and has become a major concern in healthcare due to its high prevalence worldwide. The aim of the present study was to investigate the impact of BMI on central blood pressure (BP) and pulse wave velocity (PWV) in normotensive and hypertensive patients.

PATIENTS AND METHODS

Normotensive and hypertensive adult patients who attended the outpatient clinic of cardiovascular risk were included. Peripheral BP was obtained in the brachial artery by using an oscillometric device (OMRON M-6). Central aortic BP waveform was reconstructed from the radial artery pressure waveforms (SphygmoCor, AtCor Medical, Sydney, Australia) and central BP was calculated. Carotid-femoral PWV was measured by an automatic device (Complior, Artech, France).

RESULTS

We examined a total of 351 patients [50.7% women; 77 patients normal-weight (BMI < 25 kg/m)], 274 patients overweight or obese (BMI ≥25 kg/m). Central SBP showed a positive association with male sex and mean BP, but a negative association with overweight/obesity. PWV was positively associated with age, male sex, central BP, peripheral BP and BP treatment, whereas BMI of at least 25 kg/m led to a decrease in PWV in patients with the same central SBP levels. Likewise, PWV was lower in the overweight/obese group compared to the normal-weight group at the same central SBP.

CONCLUSION

Overweight and obesity tend to have lower central SBP as compared to lean patients, mainly in women. Further research is required to assess the interaction between body weight and vascular dynamics and their clinical implications.

Measurement of Arterial Stiffness: A Novel Tool of Risk Stratification in Hypertension

Cardiovascular diseases are the leading causes of morbidity and mortality in industrialized countries worldwide, despite highly effective preventive treatments available. As a difference continues to exist between the estimated and true number of events, further improvement of risk stratification is an essential part of cardiovascular research.Among hypertensive patients measurement of arterial stiffness parameters, like carotid-femoral pulse wave velocity (cfPWV) or brachial-ankle pulse wave velocity (baPWV) can contribute to the identification of high-risk subpopulation of patients. This is a hot topic of vascular research including the possibility of the non-invasive measurement of central hemodynamics, wave reflections and recently, 24-h arterial stiffness monitoring as well. This chapter discusses the past and the present of this area including the scientific achievements with cfPWV, baPWV and other measures, provides a short overview of methodologies and the representation of arterial stiffness parameters in guidelines.

Arterial stiffness is elevated in normotensive type 2 diabetic patients with peripheral neuropathy

BACKGROUND AND AIMS

Arterial stiffness, a measure of macrovascular damage predictive of poor cardio-vascular outcomes, is strongly related to age and hypertension (HT). In diabetic patients peripheral neuropathy (PN) has been found to be associated with increased arterial stiffness, which might be due to the concomitant presence of HT. The aim of this study was to examine in type-2 diabetic patients, the relationship between arterial stiffness and presence or absence of PN and HT separately.

METHODS AND RESULTS

Arterial stiffness was measured with the gold standard carotid-femoral pulse wave velocity (PWV) in 447 type-2 diabetic subjects of whom 66% were hypertensive, 53% had PN, and 40% had both. Patients with PN were older, more often hypertensive and had higher PWV than those free of PN. Patients were separated according to the presence or absence of PN and HT. PWV values above the 90th percentile age- and blood pressure-adjusted reference range (PWV+) were different across these groups (p < 0.005) with the following respective prevalences: 27.2%, 53.4%, 33.3% and 30.6%. Only PWV+ was significantly associated with PN and hypertension in the interaction analysis.

CONCLUSION

Well controlled hypertensive patients did not have elevated arterial stiffness compared to normotensive patients. This might be due to anti-hypertensive treatment although our study design does not allow us to confirm it. A strong association between PN and arterial stiffness was only present in normotensive patients, suggesting that normotensive type 2 diabetic patients with PN and elevated arterial stiffness should be carefully managed to prevent future macrovascular complications.

Pulse pressure is not an independent predictor of outcome in type 2 diabetes patients with chronic kidney disease and anemia--the Trial to Reduce Cardiovascular Events with Aranesp Therapy (TREAT)

Pulse pressure (PP) remains an elusive cardiovascular risk factor with inconsistent findings. We clarified the prognostic value in patients with type 2 diabetes, chronic kidney disease (CKD) and anemia in the Trial to Reduce cardiovascular Events with Aranesp (darbepoetin alfa) Therapy. In 4038 type 2 diabetes patients, darbepoetin alfa treatment did not affect the primary outcome. Risk related to PP at randomization was evaluated in a multivariable model including age, gender, kidney function, cardiovascular disease (CVD) and other conventional risk factors. End points were myocardial infarction (MI), stroke, end stage renal disease (ESRD) and the composite of cardiovascular death, MI or hospitalization for myocardial ischemia, heart failure or stroke (CVD composite). Median (interquartile range) age, gender, eGFR and PP was 68 (60-75) years, 57.3% women, 33 (27-42) ml min(-1) per 1.73 m2 and 60 (50-74) mm Hg. During 29.1 months (median) follow-up, the number of events for composite CVD, MI, stroke and ESRD was 1010, 253, 154 and 668. In unadjusted analyses, higher quartiles of PP were associated with higher rates per 100 years of follow-up of all end points (P⩽0.04), except stroke (P=0.52). Adjusted hazard ratios (95% confidence interval) per one quartile increase in PP were 1.06 (0.99-1.26) for MI, 0.96 (0.83-1.11) for stroke, 1.01 (0.94-1.09) for ESRD and 1.01 (0.96-1.07) for CVD composite. Results were similar in continuous analyses of PP (per 10 mm Hg). In patients with type 2 diabetes, CKD and anemia, PP did not independently predict cardiovascular events or ESRD. This may reflect confounding by aggressive antihypertensive treatment, or PP may be too rough a risk marker in these high-risk patients.

Mechanotransduction and extracellular matrix homeostasis

Soft connective tissues at steady state are dynamic; resident cells continually read environmental cues and respond to them to promote homeostasis, including maintenance of the mechanical properties of the extracellular matrix (ECM) that are fundamental to cellular and tissue health. The mechanosensing process involves assessment of the mechanics of the ECM by the cells through integrins and the actomyosin cytoskeleton, and is followed by a mechanoregulation process, which includes the deposition, rearrangement or removal of the ECM to maintain overall form and function. Progress towards understanding the molecular, cellular and tissue-level effects that promote mechanical homeostasis has helped to identify key questions for future research.

Vascular stiffening in pulmonary hypertension: cause or consequence? (2013 Grover Conference series)

Recent studies have indicated that systemic arterial stiffening is a precursor to hypertension and that hypertension, in turn, can perpetuate arterial stiffening. Pulmonary artery (PA) stiffening is also well documented to occur in pulmonary hypertension (PH), and there is evidence that pulmonary vascular stiffness (PVS) may be a better predictor of outcome than pulmonary vascular resistance (PVR). We have hypothesized that the decreased flow-damping function of elastic PAs in PH likely initiates and/or perpetuates dysfunction of pulmonary microvasculature. Recent studies have shown that large-vessel stiffening increases flow pulsatility in the distal pulmonary vasculature, leading to endothelial dysfunction within a proinflammatory, vasoconstricting, and profibrogenic environment. The intricate role of stiffening-stimulated high pulsatile flow in endothelial cell dysfunction includes stepwise molecular events underlying PA hypertrophy, inflammation, endothelial-mesenchymal transition, and fibrosis. In addition to contributing to microenvironmental alterations of the distal vasculature, disordered proximal-distal PA coupling likely also plays a role in increasing ventricular afterload, ultimately causing right ventricle (RV) dysfunction and death. Current therapeutic treatments do not provide a realistic approach to destiffening arteries and, thus, to potentially abrogating the effects of high pulsatile flow on the distal pulmonary vasculature or the increased work imposed by stiffening on the RV. Scrutinizing the effect of PA stiffening on high pulsatile flow-induced cellular and molecular changes, and vice versa, might lead to important new therapeutic options that abrogate PA remodeling and PH development. With a clear understanding that PA stiffening may contribute to the progression of PH to an irreversible state by contributing to chronic microvascular damage in lungs, future studies should be aimed first at defining the underlying mechanisms leading to PA stiffening and then at improved treatment approaches based on these findings.