Decrease In Arterial Compliance Research Articles

Phenotyping left ventricular systolic dysfunction in asymptomatic individuals for improved risk stratification.

Left ventricular systolic dysfunction (LSVD) is a heterogeneous condition with several factors influencing prognosis. Better phenotyping of asymptomatic individuals can inform preventative strategies. This study aims to explore the clinical phenotypes of LVSD in initially asymptomatic subjects and their association with clinical outcomes and cardiovascular abnormalities through multi-dimensional data clustering. Clustering analysis was performed on 60 clinically available variables from 1563 UK Biobank participants without pre-existing heart failure (HF) and with left ventricular ejection fraction (LVEF) < 50% on cardiovascular magnetic resonance (CMR) assessment. Risks of developing HF, other cardiovascular events, death, and a composite of major adverse cardiovascular events (MACE) associated with clusters were investigated. Cardiovascular imaging characteristics, not included in the clustering analysis, were also evaluated. Three distinct clusters were identified, differing considerably in lifestyle habits, cardiovascular risk factors, electrocardiographic parameters, and cardiometabolic profiles. A stepwise increase in risk profile was observed from Cluster 1 to Cluster 3, independent of traditional risk factors and LVEF. Compared with Cluster 1, the lowest risk subset, the risk of MACE ranged from 1.42 [95% confidence interval (CI): 1.03-1.96; P < 0.05] for Cluster 2 to 1.72 (95% CI: 1.36-2.35; P < 0.001) for Cluster 3. Cluster 3, the highest risk profile, had features of adverse cardiovascular imaging with the greatest LV re-modelling, myocardial dysfunction, and decrease in arterial compliance. Clustering of clinical variables identified three distinct risk profiles and clinical trajectories of LVSD amongst initially asymptomatic subjects. Improved characterization may facilitate tailored interventions based on the LVSD sub-type and improve clinical outcomes.

Endothelial, Vascular and Sympathetic Alterations as Therapeutic Targets in Chronic Heart Failure.

Vascular and sympathetic abnormalities characterize chronic heart failure (CHF). Alterations include (1) a reduction in arterial distensibility, (2) endothelial dysfunction, (3) a decrease in arterial compliance and a parallel increase in arterial stiffness, and (4) sympathetic cardiovascular activation. Altogether, these alterations represent important targets in therapeutic interventions, because they display an independent negative impact on the disease prognosis, favouring disease progression and the development of cardiovascular complications with direct and indirect mechanisms. The present review will examine the effects of the different therapeutic interventions targeting the vascular/sympathetic alterations detected in CHF. Non-pharmacological, pharmacological and device-based treatments will be discussed in detail, highlighting the possible mechanisms responsible for the vascular/sympathetic effects of each intervention. Finally, the unmet goals in treatment in relation to endothelial and adrenergic targets will be also discussed.

Endothelial dysfunction as a new concept of early prevention of diseases of the cardiorespiratory system in workers of dust occupations

Introduction. The development of ferruginous quartzites of the Kursk magnetic anomaly basin is accompanied by the release of dust, which affects miners. Identification of markers of preclinical pathology of the cardiorespiratory system (CRS) is relevant. Objective is to identify markers of endothelial dysfunction (ED) (endothelin-1 (ET-1), brain natriuretic peptide (BNP), changes in the elastic properties of blood vessels) at the preclinical stage of the development of pathology of the cardiovascular system and pathology of the respiratory organs in workers of dust occupations with different experience. Material and methods: Medical documentation (812 persons, the period from 2008 to 2015), systematized and statistically processed. ET-1 and BNP were determined by enzyme immunoassay. The central hemodynamics was studied by the method of volumetric compression oscillometry. Results. A significant correlation was established between the prevalence of diseases of the cardiovascular system (CCC), work experience in harmful conditions, and the peculiarities of the production process, r = 0.36-0.44; r = 0.48-0.64; the development of respiratory pathology with the production process and experience, r = 0.52-0.61, r = 0.41-0.47. The structure of morbidity is mainly formed by respiratory diseases - from 5.7 % to 40%; the third rank place (7.8-10.0%) is occupied by CCC diseases. A number of the examined patients have combined cardiorespiratory pathology (CRP) - 42.4%. The changes are more typical for highly trained workers. The study revealed: an increase in the pulse wave velocity (p = 0.037); linear blood flow velocity (p = 0.029), a decrease in arterial compliance (p = 0.031) with an increase in peripheral vascular resistance (p = 0.031), signs of ED (increase in ET-1, BNP). Discussion. Changes in ET-1, BNP, elastic-elastic properties of the main vessels more often developed in highly trained workers. They manifested by the development of ED, occurring as an unfavourable factor in the early appearance and progression of bronchial obstruction followed by the formation of a chronic pulmonary heart, remodelling of the main vessels. Conclusion. The study of ED is an urgent problem for studying with the subsequent optimization of therapeutic and preventive measures at mining enterprises.

P5462Arterial hypertension, right heart remodelling and intrarenal haemodynamics: the mysterious triangle in the cardiovascular continuum

Abstract Purpose In arterial hypertension (HTN), vascular structural changes develop as a consequence of haemodynamic as well as neurohumoral factors. Indeed, in the peripheral vessels a decrease in arterial compliance and, in the heart remodelling occurs respectively. The significant impact of HTN on left heart remodelling and its interconnection with intrarenal hemodynamics (IRH) has been widely studied. In the same time, there is lack of data concerning the affinity of HTN, IRH and right heart remodelling, as another important cluster of factors for prediction of mortality and morbidity in this group of patients. Methods The study included 104 patients (50 females and 54 males, mean age 48,26±11,2 years) with grade I-III arterial hypertension. All subjects underwent careful clinical history and physical examination to reveal risk factors, cardiovascular history and treatments. Blood test, echocardiography focused on right heart evaluation, intrarenal Doppler measurements were repeated in three parts of both kidneys (superior, median, and lower) untill three reproducible waveforms were obtained. The following IRH parameters were obtained: renal resistive index (RRI), renal pulsatile index (RPI), acceleration time (AT), renal volume (RV) and RV/RRI ratio. Results The mean RRI was 0,6672±0,0452, mean RPI 1,2533±0,178, mean AT 66,68±2,324 ms, mean RV 129,67±23,79 ml and mean RV/IRR ratio 195,52±41,587 ml. Mean 24 hours SBP was 146,12±13,96 mmHg, mean 24 hours DBP 86,59±6,78 mmHg. The mean pulse pressure (PP) was 59,10±22,90 mmHg. The mean 24 hours heart rate (HR) was 75,14±26,86 beats/minute. Mean value for the right ventricular (RV) basal diameter (4Ch) was 29,5±3,71 mm, right atrium (RA) diameter 39,71±3,38 mm, RA area 16,98±2,89 mm2, Sm RV 0,11±0,05 mm/sec, TAPSE 19,2±1,66 mm, SPAP 28,3±5,321 mmHg. We found an important positive correlation between RA diameter and RA area with RRI (r=0,364, p&lt;0,01), (r=0,371, p&lt;0,01), RPI (r=0,296, p&lt;0,01), (r=0,320, p&lt;0,01) and AT (r=0,155, p&lt;0,05), (r=0,148, p&lt;0,05), and negative correlation of RV Sm with RRI (r=−0,259, p&lt;0,01), RPI (r=−0,232, p&lt;0,01), AT (r=−0,162, p&lt;0,05), meanwhile PASP showed an important positive connection with RRI (r=0,354, p&lt;0,01), RPI (r=0,330, p&lt;0,01) and AT (r=0,218, p&lt;0,01). Conclusions The assumption that cardiac structural changes are progressing in parallel with extracardiac target damage could have an important scientific substrate, emphasizing the potential connection of IRH and the heart remodelling, including the right heart in HTN, and the eventual strengthening the IRH positions as a predictor of cardiovascular outcomes in this subset of population.

A cross-sectional study of physical activity and arterial compliance: the effects of age and artery size

Our study examined the relationship between habitual high levels of vigorous physical activity on large and small artery compliance via radial artery pulse wave analysis. Eighty-three healthy men (n = 44) and women (n = 39), aged 18–78 years, were recruited as habitually less active (light-to-moderate exercise ≤3 times/wk) or habitually highly active (vigorous exercise ≥5 times/wk). A multivariate analysis of variance revealed a significant interaction of age and activity level; habitual vigorous activity was associated with greater compliance in large and small arteries in older adults (40–78 years) and younger adults (18–22 years). In the large and small arteries, we observed an age-associated decrease in arterial compliance (aged ≥ 40 years), though it appears to be less pronounced in the large artery among habitually highly active subjects. This study suggests that aging may be associated with declines in large and small artery compliance that can be attenuated by habitual vigorous activity.

Abstract 515: Comparison of Aging and Disturbed Flow Effects on Arterial Wall Biomechanics

Introduction: Arterial stiffness is an age related disease that doubles ones cardiovascular mortality and functions as an intermediary step in the formation of atherosclerosis. We have recently demonstrated that low and oscillatory wall shear stress, termed disturbed flow (d-flow), leads to arterial stiffness in otherwise normal arteries. Since d-flow has been linked to atherosclerotic plaque formation, our objective is to compare the carotid artery mechanics of 12 week arteries exposed to 4 weeks of d-flow to that of untreated 80 week old s129 mice. We hypothesize that low and oscillatory shear governs the remodeling of the arteries in a way that mimics the effect of arterial stiffening associated with aging. Materials and Methods: We used a partial carotid ligation model in 12-week-old s129 male (n=3) and female (n=3) mice. 4 weeks post surgery we euthanized the animals and performed biaxial extension-inflation biomechanical testing, confocal imaging, histological studies and opening angle studies on the left (partially ligated) carotid artery (LCA) and right (non-ligated) carotid artery (RCA) in order to characterize their biomechanical behavior. The same testing was performed on s129 80-week-old male animals (n=4). Pressure-diameter (P-d) data were collected from cyclic pressurization ramps from 0 to 160 mmHg at constant axial extension levels ranging from 1.3 to 1.9. Compliance was calculated at the in-vivo axial stretch level of 1.7 for both age groups. Intima media thickness was analyzed from H&amp;E stained histological slides. Results were compared with the unpaired, two-tailed t-test and significance was taken at p&lt;0.05. Results and Conclusions: Partial ligation for 4 weeks drastically decreased the compliance of the 12-week-old left carotid in a way that exactly follows the stiffening of the arteries in the 80-week-old mice. The compliance of the non-manipulated right carotid arteries reflected the age related difference in the stiffness of young vs old arteries with statistical difference in the 30 - 90 mmHg range. We have established that low shear stress and oscillatory flow promote the increase in arterial stiffening in the partially ligated young mice in a way that mimics the age-related decrease in arterial compliance in old mice.

Morphometric changes of the left ventricle and characteristics of peripheral hemodynamics in patients with drug resistant hypertension

Aim. To study morphometric changes of the left ventricle (LV) and characteristics of peripheral hemodynamics in patients with drug resistant hypertension (HT). Material and methods. In total, 120 patients with unmanageable HT of 2-3 degrees, that considered by physicians as drug resistant HT, were included into the study. Patients with HT resistant to full-dose triple antihypertensive therapy (n=43) were included into Group 1. Patients with HT controlled by combination therapy (n=83) were included into Group 2. All the patients underwent echocardiography, volumetric compression oscillometry (to study hemodynamic parameters). Stiffness index (SI, m/s) and reflection index (RI,%) of the pulse wave were also analyzed. Results. The increase in linear and volumetric LV sizes, severe LV hypertrophy were found in Group 1. LV mass index (LVMI) in patients in Group 1 was 134.0±6,5g/m² vs 98.4±3.3 g/m² in Group 2 (p<0.001). LVMI in men in Group 1 was 150.02±10.7 g/m² vs 99.2±4.5 g/m² in Group 2 (p<0.001). LVMI in women in Group 1 was 126±7.8 g/m vs 102.5±3.4 g/m² in Group 2 (p<0.05). The relative left ventricular wall thickness in Group 1 was 0.60, vs 0.50 in Group 2 (p<0.05). In patients of group 1 compared with group 2 there were also found a reduction in arterial compliance (0.84±0.06 vs 1.0±005, respectively; p<0.05), increased pulse wave velocity (820.14±16 vs 741.11±19 cm/sec, respectively; p<0.05), and increase in specific peripheral vascular resistance. Conclusion. Most of patients with drug resistant HT have concentric LV hypertrophy and concentric LV remodeling. The microvasculature remodeling takes place much earlier and is accompanied by possible rarefaction. Increased vascular stiffness is more pronounced in patients with drug resistant HT. It was confirmed by decrease in arterial compliance, and increase in outer diameter of the artery, that led to increase in pulse wave velocity

Effects of Isoflurane Anesthesia on Aortic Compliance and Systemic Hemodynamics in Compliant and Noncompliant Aortas

To investigate the effect of general anesthesia on aortic compliance and other cardiovascular hemodynamics in chronically instrumented pigs with compliant and noncompliant (stiff) aortas. Experimental study. University animal laboratory. Twelve adult Yucatan miniature pigs. Chronic instrumentation of a compliant (control; n = 7) and noncompliant (n = 5) group to measure pressure and flow in the ascending aorta. A Teflon prosthesis was wrapped around the aorta (noncompliant group) to limit wall compliance. Hemodynamic parameters were recorded on the 15th postoperative day, both awake and after general anesthesia. Banding the aorta caused a significant decrease in arterial compliance (-49%, p<0.001) and increases in systolic blood pressure (SBP: +38%, p = 0.001) and pulse pressure (+107%, p< 0.01). Induction of anesthesia in the control group produced a 15% increase in arterial compliance (p<0.05), resulting in a subtle decrease in SBP (-12%), diastolic blood pressure (DBP; -13%) and mean blood pressure (MBP; -12%). Induction of anesthesia in the noncompliant group also caused a significant increase in arterial compliance (17%, p<0.001), but caused significant decreases in SBP (21%, p<0.01), DBP (23%, p<0.01) and MBP (22%, p<0.01) as compared with controls. Induction of general anesthesia caused a similar increase in total arterial compliance and was associated with a decrease in SBP that was more pronounced in animals with noncompliant aortas. These results indicated that anesthesia caused a greater hemodynamic effect on noncompliant (stiff) aortas and may explain the extensive hemodynamic fluctuation and instability often observed in atherosclerotic, elderly patients with stiff aortas.

Carotid Calcification in Mice: A New Model to Study the Effects of Arterial Stiffness on the Brain

BackgroundArterial stiffness has been identified as an important risk factor for cognitive decline. However, its effects on the brain's health are unknown, and there is no animal model available to study the precise impact of arterial stiffness on the brain. Therefore, the objective of the study was to develop and characterize a new model specific to arterial stiffness in order to study its effects on the brain.Methods and ResultsCalcium chloride (CaCl2) was applied to carotid arteries of mice, inducing an increase in collagen distribution and intima–media thickness, a fragmentation of elastin, a decrease in arterial compliance and distensibility, and an increase in cerebral blood flow pulsatility (n=3 to 11). Calcium deposits were only present at the site of CaCl2 application, and there was no increase in systemic blood pressure or change in vessel radius making this model specific for arterial stiffness. The effects of carotid stiffness were then assessed in the brain. Carotid calcification induced an increase in the production of cerebral superoxide anion and neurodegeneration, detected with Fluoro‐Jade B staining, in the hippocampus (n=3 to 5), a key region for memory and cognition.ConclusionsA new model of arterial stiffness based on carotid calcification was developed and characterized. This new model meets all the characteristics of arterial stiffness, and its specificity allows the study of the effects of arterial stiffness on the brain.

Systolic Hypertension Mechanisms: Effect of Global and Local Proximal Aorta Stiffening on Pulse Pressure

Decrease in arterial compliance leads to an increased pulse pressure, as explained by the Windkessel effect. Pressure waveform is the sum of a forward running and a backward running or reflected pressure wave. When the arterial system stiffens, as a result of aging or disease, both the forward and reflected waves are altered and contribute to a greater or lesser degree to the increase in aortic pulse pressure. Two mechanisms have been proposed in the literature to explain systolic hypertension upon arterial stiffening. The most popular one is based on the augmentation and earlier arrival of reflected waves. The second mechanism is based on the augmentation of the forward wave, as a result of an increase of the characteristic impedance of the proximal aorta. The aim of this study is to analyze the two aforementioned mechanisms using a 1-D model of the entire systemic arterial tree. A validated 1-D model of the systemic circulation, representative of a young healthy adult was used to simulate arterial pressure and flow under control conditions and in presence of arterial stiffening. To help elucidate the differences in the two mechanisms contributing to systolic hypertension, the arterial tree was stiffened either locally with compliance being reduced only in the region of the aortic arch, or globally, with a uniform decrease in compliance in all arterial segments. The pulse pressure increased by 58% when proximal aorta was stiffened and the compliance decreased by 43%. Same pulse pressure increase was achieved when compliance of the globally stiffened arterial tree decreased by 47%. In presence of local stiffening in the aortic arch, characteristic impedance increased to 0.10 mmHg s/mL vs. 0.034 mmHg s/mL in control and this led to a substantial increase (91%) in the amplitude of the forward wave, which attained 42 mmHg vs. 22 mmHg in control. Under global stiffening, the pulse pressure of the forward wave increased by 41% and the amplitude of the reflected wave by 83%. Reflected waves arrived earlier in systole, enhancing their contribution to systolic pressure. The effects of local vs. global loss of compliance of the arterial tree have been studied with the use of a 1-D model. Local stiffening in the proximal aorta increases systolic pressure mainly through the augmentation of the forward pressure wave, whereas global stiffening augments systolic pressure principally though the increase in wave reflections. The relative contribution of the two mechanisms depends on the topology of arterial stiffening and geometrical alterations taking place in aging or in disease.

Arterial Compliance Decreases Following Ultra-Endurance Competition

It is well established that habitual aerobic exercise training is associated with an increase in arterial compliance. A small number of studies have examined the effects of an acute bout of aerobic exercise on measures of arterial compliance, with the conclusion that short duration exercise leads to an increased compliance. However, the response to prolonged ultra-endurance exercise is currently unclear. PURPOSE: To assess the change in arterial compliance following prolonged endurance exercise in healthy athletes with normal baseline measures. METHODS: Arterial compliance was measured non-invasively using applanation tonometery (CR-3000, HDI) at least 1 day prior to competition and approximately 30 min after completion of an ultra-endurance (120 km or 195 km) mountain trail running race. Radial arterial waveforms were collected from the right arm in conjunction with automated blood pressure on the left arm, allowing estimation of both large (capacitive arterial compliance) and small (oscillatory or reflective) artery compliance. Measures of pre- and post-race weight, seated blood pressure (BP) and heart rate were also recorded. Comparisons were made using paired t-tests and ANOVA to examine whether race distance or gender affected outcomes. Associations between race time (pace) and pre-post changes were examined using Pearson correlation. RESULTS: Race completion took approximately 25.8 ± 3.5 hr and 37.4 ±4.3 hr to complete the 120 and 195 km courses respectively with no significant difference in average pace between distances. Mean systolic and diastolic BP were maintained pre- to post-race, despite a significant decrease (4.6 ± 15.9 kg) in weight, likely reflecting fluid loss. A moderate relationship (r = 0.49, p = 0.027) existed between decreases in systolic BP and increasing age. There was no significant change in small artery compliance; however, large artery compliance decreased from 16.1 ± 4.4 to 13.6 ± 3.8 mL/mmHg × 10. CONCLUSION: Participation in prolonged ultra-endurance running led to acute decreases in arterial compliance. Further research is required to determine the effects of these changes on cardiovascular function and health.

Cerebral arterial compliance in patients with internal carotid artery disease

A decrease in arterial compliance of the internal carotid artery has been associated with an increased risk in ipsilateral ischaemic stroke. However, so far, no technique has been validated to monitor the compliance of intracerebral arteries (Ca) in patients with carotid artery disease. In this study, we sought to monitor Ca in patients with unilateral symptomatic disease and to determine its variations during changes in PaCO(2). We studied 18 patients with unilateral symptomatic internal carotid artery stenosis >50% or occlusion. Patients underwent monitoring of arterial blood pressure (ABP) and middle cerebral artery cerebral blood flow velocities (CBFV) during baseline, hyperventilation and 5%CO(2) inhalation. Ca was calculated from pulsatile amplitudes of ABP and Cerebral arterial blood volume, extracted from the CBFV waveform using a new mathematical model. At baseline, the decrease in Ca on the diseased side was correlated with the degree of stenosis (r = -0.35; P = 0.01). During hypocapnia, Ca was lower compared to baseline on the normal side (P = 0.004) and on the diseased side (P = 0.04). Ca reactivity, reflecting the changes in Ca per changes in 1 mmHg PaCO(2), was lower on the diseased side between baseline and hypocapnia (3.4 vs. 2.6%; P = 0.04). During hypercapnia, no changes in Ca on the diseased (P = 0.8) nor on the normal sides (P = 0.2) were observed. The decrease in cerebral arterial compliance the side of stenosis/occlusion was correlated with the severity of the internal carotid artery disease. Further studies are needed to determine whether Ca may improve the prediction of ischaemic events in symptomatic and asymptomatic patients.

Resistance Training Effects on Arterial Compliance in Premenopausal Women

Endurance training has been shown to increase arterial compliance; however, the effect of resistance training is unclear. The purpose of this study was to examine the effect lower body resistance training on arterial compliance in healthy premenopausal women. Thirty-two women were assigned to a resistance training group (n = 21) or a control group (n = 11). Large (C1) and small (C2) arterial compliance (Pulse Contour Analysis) were measured at baseline and after twelve weeks of training. Two-way (group x time) repeated measured ANOVA did not detect significant group, time effects or group x time interactions for small arterial compliance (P > 0.05). There was a significant time effect for large arterial compliance (P < 0.05), which increased in both groups. In contrast to previous studies in men, which found decrease in arterial compliance with resistance training, no decrease in arterial compliance was observed.

Reduction in α-adrenergic receptor-mediated vascular tone contributes to improved arterial compliance with endurance training

Background Regular aerobic exercise improves large artery compliance in middle-aged and older humans. However, the underlying mechanisms are unknown. We tested the hypothesis that the improved central arterial compliance with endurance training is mediated by decreased α-adrenergic tone and/or increased endothelial function. Methods Seven sedentary healthy adults (60 ± 3 years) underwent systemic α-adrenergic blockade (phentolamine) and nitric oxide synthase (NOS) inhibition using N G-monomethyl- l-arginine in sequence before and after a 3-month moderate endurance training (walk/jog, 4–5 days/week). Phentolamine was given first to isolate the contribution of nitric oxide to arterial compliance by minimizing reflex suppression of sympathetic tone resulting from systemic NOS inhibition as well as to assess the α-adrenergic receptor-mediated modulation of arterial compliance. Results Baseline arterial compliance (via simultaneous ultrasound and applanation tonometry on the carotid artery) increased 34 ± 12% after exercise training ( P < 0.01). When α-adrenergic blockade was performed, arterial compliance increased 37 ± 6% ( P < 0.01) before the exercise training but did not change significantly after the training. Decreases in arterial compliance from the α-adrenergic blockade to the subsequent additional NOS blockade were not different before and after exercise training. Conclusion Our results suggest that the reduction in α-adrenergic receptor-mediated vascular tone contributes to the improved central arterial compliance with endurance training.

Reduction in Alpha-Adrenergic Receptor-Mediated Vascular Tone Contributes to Improved Arterial Compliance with Endurance Training

PURPOSE: Regular aerobic exercise improves large artery compliance in middleaged and older humans. However, the underlying mechanisms are unknown. We tested the hypothesis that the improved central arterial compliance with endurance training is mediated by decreased α-adrenergic tone and/or increased endothelial function. METHODS: Seven sedentary healthy adults (61±2 yr) underwent systemic α-adrenergic blockade (phentolamine) and nitric oxide synthase (NOS) inhibition using NG-monomethyl-L-arginine in sequence before and after a 3-month moderate endurance training (walk/jog, 4-5 days/week). Phentolamine was given first to isolate the contribution of nitric oxide to arterial compliance by minimizing reflex suppression of sympathetic tone resulting from systemic NOS inhibition as well as to assess the α-adrenergic receptor-mediated modulation of arterial compliance. RESULTS: Baseline arterial compliance (via simultaneous ultrasound and applanation tonometry on the carotid artery) increased 34±12% after exercise training (P<0.01). When α-adrenergic blockade was performed, arterial compliance increased 37±6% (P<0.01) before the exercise training but did not change significantly after the training. Decreases in arterial compliance from the α-adrenergic blockade to the subsequent additional NOS blockade were not different before and after exercise training. CONCLUSIONS: Our results suggest that the reduction in α-adrenergic receptormediated vascular tone contributes to the improved central arterial compliance with endurance training.

Effect of unilateral resistance training on arterial compliance in elderly men

An increase in age coincides with a decrease in arterial compliance, which is related to a higher risk for cardiovascular accidents. Evidence regarding the effects of resistance training on arterial compliance is conflicting. Currently, little information is available about the effect of resistance training on arterial compliance in elderly men. We assessed the impact of 10 weeks of unilateral arm and leg resistance training on carotid, brachial, and femoral arterial compliance in 12 healthy elderly men (mean age +/- SD, 71 +/- 7 y). Arterial compliance was evaluated before, after 4 weeks, and after 10 weeks of unilateral resistance training by simultaneously measuring arterial diameter and blood pressure in each artery. There were no significant differences in arterial compliance or stiffness index in any of the arteries examined after 10 weeks of training. However, after 10 weeks of resistance training, resting heart rate decreased from 76 +/- 4 beats/min to 61 +/- 3 beats/min (p < 0.05), plasma glucose decreased from 6.0 +/- 0.9 to 5.1 +/- 0.9 mmol/L (mean +/- SE) (p < 0.05), and carotid artery peak blood flow increased from 1831 mL/min to 2245 mL/min (p < 0.05). There were no significant changes in resting arterial blood pressure. Unilateral resistance training for 10 weeks does not alter peripheral and central arterial compliance elderly men.

Changes in vascular flow after transdermal oestradiol therapy for prostate cancer: a mechanism for cardiovascular toxicity and benefit?

To report the influence of transdermal oestradiol therapy on the vascular dynamics of men with advanced prostate cancer. Twenty patients with newly diagnosed locally advanced or metastatic prostate cancer (10 each) were treated using transdermal oestradiol patches. The vascular flow was assessed 6-monthly before and during a year of therapy using arterial and venous Doppler and duplex ultrasonography, arterial and venous photoplethysmography and opto-electronic plethysmography. Arterial flow, as measured by the mean and peak systolic velocities and photoplethysmography, significantly increased over time. Arterial compliance initially decreased but had normalized after 12 months. The venous variables were unaffected. As a result, the total limb blood flow and the capillary filtration rate were significantly increased. Transdermal oestradiol therapy causes an increase in arterial but not venous flow, and an initial decrease in arterial compliance, which adapts to the physiological range with time. It is possible that these changes may account for the increase in cardiovascular toxicity seen in the early phase of oestrogen therapy, and the cardioprotective effect that accrues thereafter.

Treating Stage 2 Hypertension

The prevalence of hypertension increases with advancing age, due primarily to increases in systolic blood pressure. Systolic hypertension is the most common form of hypertension in individuals over 50 years of age and reflects pathologic decreases in arterial compliance. Systolic blood pressure elevation is a more important risk factor for cardiovascular disease than is diastolic blood pressure elevation. Stage 2 hypertension, defined as blood pressure > or =160/100 mm Hg, is often found in older persons, who are at highest risk for cardiovascular events. In this clinical review, hypertension experts utilize a case study to provide a paradigm for treating older patients with stage 2 hypertension.

Hemodynamics and arterial properties in response to mental stress in individuals with mild hypertension.

The role of tonic sympathetic stimulation on the properties of large arteries is largely unknown. The purpose of this study was to determine the effect of mental stress on hemodynamics and arterial properties in mild hypertensives. Twenty-three subjects with mild hypertension and 19 age-matched normotensives were compared to examine changes in hemodynamics and central arterial wave reflection before, during, and after mental stress. The results demonstrate an acute effect of mental stress on blood pressure, heart rate, and arterial compliance. The static component (MBP) and the pulsatile (PP) component of arterial pressure increased significantly during mental stress and returned to baseline within a few minutes. Mild hypertensives did not have an increased response to mental stress. For both groups, an increase in HR and a consequent rise in CO were responsible for the increase in BP in response to mental stress. Compared with baseline, both groups demonstrated a decrease in arterial compliance during stress. Mental stress did not induce a significant change in total peripheral vascular resistance nor did it affect central arterial wave reflection in both groups. Individuals with mild hypertension demonstrated higher PP (p <.001), lower arterial compliance (p <.01), and higher AI (p <.05) than those with normal BP. Hemodynamic and arterial responses to mental stress in individuals with normal BP and mild hypertension were similar. Several parameters, however, were different in basal state. These differences (ie, higher PP, lower compliance, and higher AI in the mild hypertensive group) could be due to the chronic effect of sympathetic stimulation on central arteries.

Effects of nicotine on small and large arterial compliances in non-smokers

Epidemiological studies have demonstrated that a decrease in arterial compliance is associated with hypertension and coronary artery disease. Decreased arterial compliance is thought to occur at early stage of cardiovascular disease. Smoking is considered one of the important risk factors for cardiovascular disease. However, effects of smoking on arterial compliance are not well studied. We examined the effects of nicotine patch on small and large arterial compliances in 10 healthy normotensive, nonsmokers. The study group consisted of 4 males and 6 females with mean age of 42 ± 12 years. A 7 mg nicotine patch (equivalent to 10 cigarettes a day) was placed on the right forearm. Heart rate (HR), systolic BP (SBP), diastolic BP (DBP), stroke volume, cardiac output, large artery elasticity index (LAEI), small artery elasticity index (SAEI), and systemic vascular resistance (SVR) were measured noninvasively using a HDI/Pulse wave (CR-2000) from radial artery waveforms. After 10 to 15 minutes of supine rest, measurements were made for pre-nicotine patch baseline. Then measurements were repeated every 20 minutes for a period of 2 hours after nicotine patch was placed. There was no significant change in any parameters within 60 minutes. Changes in BP, arterial compliance and SVR begin to occur at 80 minute in some subjects and continued at 120 minutes. There were no significant changes in HR, stroke volume and cardiac output. The results at baseline and 60 minutes and 120 minutes post nicotine patch are summarized in the table. In conclusion, nicotine in a low dose raises blood pressure, vascular resistance and decreases small and large artery compliances. An increased arterial stiffness in response to nicotine may be one of the mechanisms that smoking contributes to cardiovascular disease. Effects of nicotine in chronic smokers require further studies. Values are mean (SD). p < 0.05 from baseline. Values are mean (SD). p < 0.05 from baseline.