BackgroundIncreased vascular tortuosity is a hallmark of ageing of the vascular system, including the aorta. However, the impact of tortuosity on aortic blood flow is unknown. We hypothesized that increased tortuosity would be associated with increased blood flow helicity and with decreased degree of blood flow turbulence as measured by the turbulent kinetic energy (TKE).Methods4D Flow MR images covering the entire aorta from the aortic valve to the iliac bifurcation were acquired in 23 normal volunteers aged 18-30 years ("Young") and 23 normal volunteers aged 66-76 years ("Old") without aortic disease. The aorta was segmented and divided into four regions: the ascending, descending, suprarenal abdominal and infrarenal abdominal aorta. Tortuosity, helicity, TKE, flow velocity, and Reynolds number were computed for the whole aorta and for each section.ResultsTortuosity and helicity were higher whereas TKE, velocity, and Reynolds number were lower in Old than in Young, for all aortic regions (p < 0.05) except for helicity in the descending aorta. Tortuosity correlated positively with helicity and negatively with TKE for all aortic regions (Spearman rho=+/- 0.45-+/- 0.72, p < =0.002) except for TKE in the ascending aorta. Further, helicity correlated with TKE in the descending, suprarenal abdominal and infrarenal abdominal aorta (Spearman rho=-0.56--0.77).ConclusionTortuosity increases with age and blood flow in tortuous aortas is more helical. Increasing helicity, in turn, is associated with decreasing TKE.

Introduction: Takayasu arteritis (TAK) is a rare inflammatory disease affecting aorta and its major branches. Ultrasound (US) can detect inflammatory features in the arterial wall, but less is known regarding skin microcirculation and vascular hemodynamics. The aim was to study if assessment of these variables could add valuable information regarding vascular affection in TAK.Methods: 17 patients diagnosed with TAK and 17 age- and sex-matched healthy controls were included. Microcirculatory peak oxygen saturation (OxyP) in the skin after induced ischemia was evaluated with laser Doppler flowmetry/diffuse reflectance spectroscopy. Cerebrovascular reserve capacity (CVR) in the brain was assessed with transcranial Doppler (TCD). Pulse waves were recorded in the radial artery by the aid of applanation tonometry, for calculation of central augmentation index (AIx75). Intima-media thickness (IMT) and stenosis/occlusions were evaluated using US in carotid and central arteries.Results: Reduced OxyP (79 +/- 8% vs. 87 +/- 4%, p < 0.001) was seen in patients with TAK regardless of significant arterial stenosis/occlusion or not. Increased AIx75 (22.3 +/- 13.6 vs. 9.2 +/- 16.3, p = 0.01) was seen in TAK patients without significant stenosis/occlusions. No differences were found in CVR, regardless of proximal stenosis. However, signs of a more high-resistance flow profile were seen in arteria cerebri media.Conclusion: Regardless of arterial stenosis or not, impaired microcirculation of the skin and preserved CVR in the brain were found in subjects with TAK. Signs of increased arterial stiffness in the brain and central arteries were observed. The value of these findings for prediction of future cardiovascular events needs to be clarified in further studies.

Objective: Abdominal aortic aneurysm (AAA) is associated with dilatation of central elastic arteries, while it is uncertain whether peripheral muscular arteries are affected. The aim of this study was to investigate radial artery diastolic lumen diameter (LD), wall thickness, and circumferential wall stress (CWS) in patients with AAA. Methods: We included 130 men with AAA (mean age, 70.4 ± 3.5 years) and 61 men without AAA (mean age, 70.5 ± 3.2 years) in the study. High-frequency ultrasound examination (50 MHz) was used to measure radial artery diameter, wall thickness, and CWS was calculated. Results: Men with AAA exhibited smaller radial artery LD (2.34 ± 0.42 mm vs 2.50 ± 0.38 mm; P <.01), thicker intima (0.094 ± 0.024 mm vs 0.081 ± 0.018 mm; P <.001), similar intima-media (0.28 ± 0.05 vs 0.26 ± 0.05 mm; P = NS), and lower CWS (42.9 ± 10.2 kPa vs 48.6 ± 11.4 kPa; P <.001), compared with controls. Subgroup analyses including all patients showed smaller LD and thicker intima in patients on statin therapy versus no statin therapy and current/ex-smoking versus never smoking. Individuals with hypertension versus no hypertension also presented with thicker intima, but with no difference in LD. Conclusions: AAAs demonstrated a smaller LD and thicker intima in the radial artery, in contrast with the theory of a general dilating diathesis of the arteries. Apart from AAA, other factors such as atherosclerosis, smoking habits, and hypertension might also be determinants of radial artery caliber and thickness. Clinical Relevance: The clinical relevance of this study is the added insight into the pathophysiology of abdominal aortic aneurysm (AAA). Today, the management of AAA is focused on reduction of general cardiovascular risk factors and treatment is based on surgical approaches when the AAA is already manifest. By shedding light on unknown pathophysiological aspects of AAA, it will eventually be possible to develop targeted pharmacological treatments to prevent the formation of AAA, to halt disease progression, and to find early cardiovascular markers of AAA. © 2022 Society for Vascular Surgery

Background Abdominal aortic aneurysms (AAA) can lead to catastrophic events such as dissection or rupture, and are an expression of general aortic disease. Low wall shear stress (WSS), high oscillatory shear index (OSI), and high relative residence time (RRT) have been correlated against increased uptake of inflammatory markers in the vessel wall and may improve risk stratification of AAA. We sought to obtain a comprehensive view of WSS, OSI, and RRT in the whole aorta for patients with AAA and age-matched elderly controls and young normal controls. Methods 4D Flow cardiovascular magnetic resonance images of the whole aorta were acquired in 18 AAA patients (70.8 +/- 3.4 years), 22 age-matched controls (71.4 +/- 3.4 years), and 23 young subjects (23.3 +/- 3.1 years), all males. Three-dimensional segmentations of the whole aorta were created for all timeframes using a semi-automatic approach. The aorta was divided into five segments: ascending aorta, arch, descending aorta, suprarenal and infrarenal abdominal aorta. For each segment, average values of peak WSS, OSI, and RRT were computed. Students t-tests were used to compare values between the three cohorts (AAA patients vs elderly controls, and elderly controls vs young controls) where the data were normally distributed, and the non-parametric Wilcoxon rank sum tests were used otherwise. Results AAA patients had lower peak WSS in the descending aorta as well as in the abdominal aorta compared to elderly controls (p <= 0.001), similar OSI, but higher RRT in the descending and abdominal aorta (p <= 0.001). Elderly controls had lower peak WSS compared to young controls throughout the aorta (p < 0.001), higher OSI in all segments except for the infrarenal aorta (p < 0.001), and higher RRT throughout the aorta, except the infrarenal aorta (p < 0.001). Conclusions This study provides novel insights into WSS, OSI, and RRT in patients with AAA in relation to normal ageing, highlighting how AAA patients have markedly abnormal hemodynamic stresses not only in the infrarenal, but in the entire aorta. Moreover, we identified RRT as a marker for abnormal AAA hemodynamics. Further investigations are needed to explore if RRT or other measures of hemodynamics stresses best predict AAA growth and/or rupture.

Background During the cardiac cycle, there is a multi-phasic bidirectional longitudinal movement (LMov) of the intima-media complex of large arteries, i.e. along the arteries. On the left side the common carotid artery (CCA) arises directly from the aortic arc, whereas on the right side the CCA originate from the innominate artery. Aim The aim of this study was to compare LMov of the left and right CCA of healthy subjects to investigate whether the difference in anatomy is of importance for LMov. Material and Methods The CCAs of 93 healthy subjects were investigated using in-house developed ultrasound methods. Results Although the basic pattern were the same in the majority of subjects, several phases of LMov were significantly larger on the left side (the first retrograde phase, p = 0.0006; the second antegrade, "returning" phase, p < 0.00001; and the rapid retrograde phase of movement at the end of the cardiac cycle, p < 0.000001). In contrast, no significant side-difference in the amplitude of the first antegrade movement was seen. The maximal (peak-to-peak) LMov was significantly larger on the left side (p = 0.002). Discussion and Conclusion The side-differences found in LMov may be related to the difference in anatomy, including possible difference in distance to the heart and especially the presence of an extra bifurcation on the right side. Our data provide an important base for the further study of the relation between LMov and cardiovascular risk factors and atherosclerosis.

Introduction: Systemic lupus erythematosus (SLE) is associated with premature cardiovascular disease (CVD) and mortality, unexplained by traditional risk factors. Impairment of microcirculation and vascular hemodynamics may represent early signs of vascular affection. We hypothesized that studies of microcirculation and pulse waves may provide additional information, compared to ultrasound (US) alone, for the detection of early vascular disease in SLE.Methods: Sixty well-characterized SLE-patients (52 women, eight men; mean age 43.21 +/- 1.3 years) characterized by lupus nephritis (LN; n = 20), antiphospholipid syndrome (APS; n = 20) or skin and joint involvement (n = 20) and 60 healthy controls were included. Microcirculatory peak oxygen saturation (OxyP) was evaluated using a novel combined laser Doppler flowmetry/diffuse reflectance spectroscopy method. Pulse waves were recorded in the radial artery by the aid of applanation tonometry in order to calculate central augmentation index (AIx75). Intima-media thickness (IMT) and plaque occurrence were evaluated using high frequency US, in carotid and central arteries.Results: Lower OxyP (84 +/- 8 vs. 87 +/- 5 %, p = 0.01) and higher AIx75 (17.3 +/- 13.9 vs. 10.0 +/- 14.2 %, p = 0.005) were seen in the SLE cohort. OxyP was inversely correlated with IMT in internal carotid artery (ICA), (R = -0.32, p = 0.01). AIx75 correlated with IMT in common carotid artery (CCA), (R = 0.36, p = 0.005), common femoral artery (CFA), (R = 0.43, p = 0.001), and ICA (R = 0.27, p = 0.04). AIx75 correlated negatively with OxyP (R = -0.29, p = 0.02). SLE-patients with plaque had lower OxyP values (80 +/- 8 vs. 85 +/- 7 %, p < 0.001) and higher AIx75 (23.0 +/- 11.6 vs. 15.5 +/- 14.2 %, p < 0.001) compared to those without plaque.Conclusion: Impaired microcirculation and vessel hemodynamics were observed in SLE. These methods correlated with IMT and plaque occurrence. The importance of early macro- and micro-circulatory vascular affection for increased risk of CVD in SLE will be followed-up in future studies.

Background Abdominal aortic aneurysm (AAA), a localized dilatation of the abdominal aorta, has a prevalence of about 1.5%-3% among 65- to 70-year-old males in Europe. AAA confers an increased risk of developing major cardiovascular events in addition to the risk of aneurysm rupture. The aim of this study was to evaluate whether the arterial wall distensibility is altered in subjects with AAA. Methods Two hundred and eighty-four male subjects (182 with AAA and 102 controls) were enrolled in the study. Arterial wall distensibility was evaluated using non-invasive applanation tonometry to measure regional pulse wave velocity between the carotid and femoral arteries and the carotid and radial arteries. In addition, blood pressure was measured, and the pulse pressure waveform was analysed. Results Higher aortic augmentation index (25.1% versus 20.6%;p < .001) and higher aortic pulse wave velocity (12.3 m/s versus 10.9 m/s;p < .001) were demonstrated in the AAA cohort. The slightly higher arm pulse wave velocity in the AAA group (9.4 m/s versus 9.1 m/s;p < .05) was abolished after adjusting for mean arterial blood pressure. Conclusions Males with AAA have decreased aortic wall distensibility and enhanced reflection waves in central aorta during systole. These results imply that increased arterial wall stiffness may be a contributing factor to the overall higher cardiovascular risk seen in patients with AAA.

Objective

Metformin is associated with a reduced incidence and growth of abdominal aortic aneurysms (AAAs). The aim of the present study was to investigate the inhibitory effects of metformin on AAA development and possible underlying mechanisms in experimentally induced AAAs in mice, along with the possible synergistic effects of metformin and imatinib.

Methods

Angiotensin II was used to induce AAAs in apolipoprotein E knockout (ApoE−/−) mice for 28 days. The mice were treated with metformin (n = 11), metformin combined with imatinib (n = 7), or vehicle (n = 12), starting 3 days before angiotensin II infusion. Ultrasound examination was used to analyze aneurysm formation. Cholesterol and blood pressure levels were measured at the start and end of the study. Gene array and quantitative polymerase chain reaction were used to analyze the changes in gene expression in the aorta. Wire myography was used to study vascular function.

Results

Metformin (n = 11) suppressed the formation and progression of AAAs by 50% compared with the vehicle controls (n = 12), with no further effects from imatinib (n = 7). Metformin reduced total cholesterol and mRNA expression of SPP1 (encoding osteopontin), MMP12, and the glycoprotein genes Gpnmb and Clec7a. Furthermore, metformin inhibited blood pressure increases and reduced vascular contractions, as determined by wire myography, and restored the anticontractile function of perivascular adipose tissue.

Conclusion

Metformin inhibited aneurysm formation and progression and normalized vascular function in ApoE−/− mice with no additional effect of imatinib. This might be mediated by the protective effects on vascular endothelial function and perivascular adipose tissue via reduced expression of genes promoting inflammation, including SPP1, MMP12, Gpnmb, and Clec7a.

Background: Recent reports suggest that the negative association between diabetes mellitus and abdominal aortic aneurysm (AAA) may be driven by metformin, the worlds most common anti-diabetic drug rather than diabetes per se. We sought to investigate the association among AAA growth rate, chemokine profile, and metformin prescription in a contemporary Swedish cohort. Methods: Patients under surveillance for small AAA were identified at 4 Swedish vascular centers with active AAA screening programs. Annual AAA growth rate, medical history, and prescribed medications were recorded for linear regression analysis. In a subset of patients with AAA and control subjects without AAA or diabetes, plasma samples were available and analyzed for 40 inflammatory chemokines. Results: A total of 526 patients were included for AAA growth analysis: 428 without type 2 diabetes mellitus (T2DM), 65 with T2DM and metformin prescription, and 33 with T2DM but without metformin prescription. Patients were included from 2005 to 2017 with mean follow-up of 3.2 (1.7) years and median annual AAA growth rate 1.6 mm, range -4.8 to 15.4 mm. Mean (standard deviation) annual AAA growth rates were 2.3 (2.2) mm in non-T2DM patients versus 1.1 (1.1) mm in patients with T2DM with metformin prescription and 1.6 (1.4) mm among those with T2DM without metformin prescription. With non-T2DM patients as reference in an unadjusted and 2 adjusted models, metformin prescription was significantly associated with reduced AAA growth rate (P < 0.001, P = 0.005, and P = 0.024, respectively), but not T2DM without metformin prescription (P = 0.137, P = 0.331, and P = 0.479, respectively). Among 240 patients with AAA (152 without T2DM, 51 with T2DM and metformin, and 37 with T2DM without metformin) and 59 without AAA or T2DM, metformin prescription was associated with reduced expression of chemokines representing all classes of leukocytes. Conclusions: Metformin prescription is associated with reduced AAA growth rate, possibly mediated by broad anti-inflammatory effects. A randomized controlled trial is needed to determine what role metformin may play in AAA disease, particularly in the absence of T2DM.

Cryoablation, which induces cellular death without extensive tissue damage, has been extensively used to denervate the myocardium. However, periadventitial external circumferential application of cryotherapy to denervate the renal artery sympathetic nerves has, to our knowledge, never been tested in humans. The main aim of this study was to examine the safety and potential effects of cryotherapy on ambulatory blood pressure levels and other outcomes that are indirectly related to sympathetic tone, including pulse-wave velocity, central pulse pressure, and glucose levels.

Objective: Abdominal aortic aneurysm (AAA) is associated with morphological and functional changes in both aneurysmal and non-aneurysmal arteries. However, it remains uncertain whether similar changes also exist in the venous vasculature. The aim of this study was to evaluate global venous function in patients with AAA and controls. Methods: This experimental study comprised 31 men with AAA (mean +/- standard deviation age 70.0 +/- 2.8 years) and 29 male controls (aged 70.6 +/- 3.4 years). Venous occlusion plethysmography (VOP) was used to evaluate arm venous compliance at venous pressures between 10 and 60 mmHg in steps of 5 mmHg. Compensatory mobilisation of venous capacitance blood (capacitance response) was measured with a volumetric technique during experimental hypovolaemia induced by lower body negative pressure (LBNP). Results: The VOP induced pressure-volume curve was significantly less steep in patients with AAA (interaction, p < .001), indicating lower venous compliance. Accordingly, the corresponding pressure-compliance curves displayed reduced venous compliance at lower venous pressures in patients with AAA vs. controls (interaction, p < .001; AAA vs. control, p = .018). After adjusting for arterial hypertension, diabetes mellitus, hyperlipidaemia, chronic obstructive pulmonary disease, and smoking, VOP detected differences in venous compliance remained significant at low venous pressures, that is, at 10 mmHg (p = .008), 15 mmHg (p = .013), and 20 mmHg (p = .026). Mean venous compliance was negatively correlated with aortic diameter (r = -.332, p = .010). Mobilisation of venous capacitance response during LBNP was reduced by approximately 25% in patients with AAA (p = .030), and the redistribution of venous blood during LBNP was negatively correlated with aortic diameter (r = -.417, p = .007). Conclusion: Men with AAA demonstrated reduced venous compliance and, as a result, a lesser capacity to mobilise peripheral venous blood to the central circulation during hypovolaemic stress. These findings imply that the AAA disease may be accompanied by functional changes in the venous vascular wall.

The early vascular adaptation to indoor cycling, a popular activity at many fitness centres, is incompletely evaluated. Forty two healthy women (21-45 years) underwent measurements of arterial wall properties and geometry as well as a maximal bicycle exercise test before and after a 3 months period during which 21 of the women joined indoor cycling classes at a gym 2-3 times per week, while 21 women served as time controls. Peak work load increased by in average 16% (pamp;lt;0.001) and ascending aortic diameter by 4% (pamp;lt;0.01) in the exercise group, while unchanged in control group. The exercise intervention had no significant influence on the local intima-media thickness, blood pressure or the pulse pressure wave configuration while the carotid artery distensibility (pamp;lt;0.05) was higher after the intervention. There was a positive correlation between change in () peak work load and -diameter of tubular ascending aorta (r=0.42, pamp;lt;0.01) in the exercise group. In conclusion, after only 3 months of bicycle exercise training, signs of central arterial remodelling were seen in premenopausal women, which was associated to improvement in exercise capacity.

Purpose: To examine methods for visualizing and quantifying flow stasis in abdominal aortic aneurysms (AAA) using 4D Flow MRI. Methods: Three methods were investigated: conventional volumetric residence time (VRT), mean velocity analysis (MVA), and particle travel distance analysis (TDA). First, ideal 4D Flow MRI data was generated using numerical simulations and used as a platform to explore the effects of noise and background phase-offset errors, both of which are common 4D Flow MRI artifacts. Error-free results were compared to noise or offset affected results using linear regression. Subsequently, 4D Flow MRI data for thirteen (13) subjects with AAA was acquired and used to compare the stasis quantification methods against conventional flow visualization. Results: VRT (R-2 = 0.69) was more sensitive to noise than MVA (R-2 = 0.98) and TDA (R-2 = 0.99) at typical noncontrast signal-to-noise ratio levels (SNR = 20). VRT (R-2 = 0.14) was more sensitive to background phase-offsets than MVA (R-2 = 0.99) and TDA (R-2 = 0.96) when considering a 95% effective background phase-offset correction. Qualitatively, TDA outperformed MVA (Wilcoxon p amp;lt; 0.005, mean score improvement 1.6/5), and had good agreement (median score 4/5) with flow visualizations. Conclusion: Flow stasis can be quantitatively assessed using 4D Flow MRI. While conventional residence time calculations fail due to error accumulation as a result of imperfect measured velocity fields, methods that do not require lengthy particle tracking perform better. MVA and TDA are less sensitive to measurement errors, and TDA generates results most similar to those obtained using conventional flow visualization.

Turbulent blood flow is implicated in the pathogenesis of several aortic diseases but the extent and degree of turbulent blood flow in the normal aorta is unknown. We aimed to quantify the extent and degree of turbulece in the normal aorta and to assess whether age impacts the degree of turbulence. 22 young normal males (23.7 +/- 3.0 y.o.) and 20 old normal males (70.9 +/- 3.5 y.o.) were examined using four dimensional flow magnetic resonance imaging (4D Flow MRI) to quantify the turbulent kinetic energy (TKE), a measure of the intensity of turbulence, in the aorta. All healthy subjects developed turbulent flow in the aorta, with total TKE of 3-19 mJ. The overall degree of turbulence in the entire aorta was similar between the groups, although the old subjects had about 73% more total TKE in the ascending aorta compared to the young subjects (young = 3.7 +/- 1.8 mJ, old = 6.4 +/- 2.4 mJ, p amp;lt; 0.001). This increase in ascending aorta TKE in old subjects was associated with age-related dilation of the ascending aorta which increases the volume available for turbulence development. Conversely, age-related dilation of the descending and abdominal aorta decreased the average flow velocity and suppressed the development of turbulence. In conclusion, turbulent blood flow develops in the aorta of normal subjects and is impacted by age-related geometric changes. Non-invasive assessment enables the determination of normal levels of turbulent flow in the aorta which is a prerequisite for understanding the role of turbulence in the pathophysiology of cardiovascular disease.

A method for computer-aided assessment of blood vessel geometries based on shape-fitting algorithms from metric vision was evaluated. Acoustic images of cross sections of the radial artery and cephalic vein were acquired, and medical practitioners used a computer application to measure the wall thickness and nominal diameter of these blood vessels with a caliper method and the shape-fitting method. The methods performed equally well for wall thickness measurements. The shape-fitting method was preferable for measuring the diameter, since it reduced systematic errors by up to 63% in the case of the cephalic vein because of its eccentricity.

Putative changes in the multiphasic pattern of longitudinal movement of the common carotid artery wall in the normal aging process are unknown. The aim of this study was to explore the phases, and resulting patterns, of the longitudinal movement of the intima-media complex of the human common carotid artery with respect to age and gender. One hundred thirty-five healthy non-smoking patients of different ages were investigated using in-house-developed ultrasound methods. The patterns of longitudinal movement seen in middle-aged and older patients were markedly different from those commonly seen in young patients, including the appearance of two additional phases of motion and, thus, new complex patterns. The displacement and maximum velocity of one of the phases, occurring at the time of aortic valve closure, increased quadratically with age in both men and women. (C) 2018 World Federation for Ultrasound in Medicine amp; Biology. All rights reserved.

AimTo explore whether high-level endurance training in early age has an influence on the arterial wall properties in young women. MethodsForty-seven athletes (ATH) and 52 controls (CTR), all 17-25 years of age, were further divided into runners (RUN), whole-body endurance athletes (WBA), sedentary controls (SC) and normally active controls (AC). Two-dimensional ultrasound scanning of the carotid arteries was conducted to determine local common carotid artery (CCA) geometry and wall distensibility. Pulse waves were recorded with a tonometer to determine regional pulse wave velocity (PWV) and pulse pressure waveform. ResultsCarotid-radial PWV was lower in WBA than in RUN (P amp;lt; .05), indicating higher arterial distensibility along the arm. Mean arterial pressure was lower in ATH than in CTR and in RUN than in WBA (P amp;lt; .05). Synthesized aortic augmentation index (AI@75) was lower among ATH than among CTR (-12.8 1.6 vs -2.6 +/- 1.2%, P amp;lt; .001) and in WBA than in RUN (-16.4 +/- 2.5 vs -10.7 +/- 2.0%, P amp;lt; .05), suggesting a diminished return of reflection waves to the aorta during systole. Carotid-femoral PWV and intima-media thickness (IMT), lumen diameter and radial distensibility of the CCA were similar in ATH and CTR. ConclusionElastic artery distensibility and carotid artery IMT are not different in young women with extensive endurance training over several years and in those with sedentary lifestyle. On the other hand, our data suggest that long-term endurance training is associated with potentially favourable peripheral artery adaptation, especially in sports where upper body work is added. This adaptation, if persisting later in life, could contribute to lower cardiovascular risk.

Cross-sectional studies provide evidence of larger cardiac dimensions and mass in endurance trained than in untrained females. Much less is known regarding adaptations in cardiac function following training in untrained subjects. We aimed to study left ventricular (LV) adaptation to indoor cycling in previously untrained females, in regard of LV dimensions, mass and function. 42 sedentary females were divided into 2 equally sized groups, either training indoor cycling at regular classes at a local gym for 12 weeks, in average 2.6 times per week, or maintaining their sedentary lifestyle. Echocardiography at rest and a maximal exercise test were performed before and after the intervention. Exercise capacity increased in average 16% in the exercise group (p<0.001), together with decreased heart rate at rest (p<0.05) and at 120 watts steady-state (p<0.001). There were no difference in systolic or diastolic function following the intervention and minimal increases in LV internal diameter in diastole (+1 mm, p<0.01). LV mass was unchanged with training (137±25 vs. 137±28 g, p=0.911). Our findings indicate that attending indoor cycling classes at a gym 2-to-3 times per week for 12 weeks is enough to improve exercise capacity, while a higher volume of training is required to elicit cardiac adaptations.

Skin and kidney microvascular functions may be affected independently in diabetes mellitus. We investigated skin microcirculatory function in 79 subjects with diabetes type 2, where 41 had microalbuminuria and 38 not, and in 41 age-matched controls. The oxygen saturation, fraction of red blood cells and speed-resolved microcirculatory perfusion (% red blood cells x mm/s) divided into three speed regions: 0-1, 1-10 and above 10 mm/s, were assessed during baseline and after local heating of the foot with a new device integrating diffuse reflectance spectroscopy and laser Doppler flowmetry. Arterial stiffness was assessed as carotid-femoral pulse wave velocity. Subjects with diabetes and microalbuminuria had significantly higher carotid-femoral pulse wave velocity compared to subjects without microalbuminuria and to controls. The perfusion for speeds 0-1 mm/s and red blood cell tissue fraction were reduced in subjects with diabetes at baseline and after heating, independent of microalbuminuria. These parameters were correlated to HbA1c. In conclusion, the reduced nutritive perfusion and red blood cell tissue fraction in type 2 diabetes were related to long-term glucose control but independent of microvascular changes in the kidneys and large-vessel stiffness. This may be due to different pathogenic pathways in the development of nephropathy, large-vessel stiffness and cutaneous microvascular impairment.

The aim of the study was to explore the long-and short-axis dimensions, shape and collapsibility of the inferior vena cava in 46 trained and 48 untrained females (mean age: 21 +/- 2 y). Echocardiography in the subcostal view revealed a larger expiratory long-axis diameter (mean: 24 +/- 3 vs. 20 +/- 3 mm, p amp;lt; 0.001) and short-axis area (mean: 5.5 +/- 1.5 vs. 4.7 +/- 1.4 cm(2), p = 0.014) in trained females. IVC shape (the ratio of short-axis major to minor diameters) and the relative decrease in IVC dimension with inspiration were similar for the two groups. The IVC long-axis diameter reflected short-axis minor diameter and was correlated to maximal oxygen uptake (r = 0.52, p amp;lt; 0.01). In summary, the results indicate that trained females have a larger IVC similar in shape and respiratory decrease in dimensions to that of untrained females. The long-axis diameter corresponded closely to short-axis minor diameter and, thus, underestimates maximal IVC diameter. (E-mail: kristofer.hedman@liu.se) (C) 2016 The Authors. Published by Elsevier Inc. on behalf of World Federation for Ultrasound in Medicine amp; Biology.

Background Most studies on cardiac function in athletes describe overall heart function in predominately male participants. We aimed to compare segmental, regional and overall myocardial function and synchrony in female endurance athletes (ATH) and in age-matched sedentary females (CON).

Methods In 46 ATH and 48 CON, echocardiography was used to measure peak longitudinal systolic strain and myocardial velocities in 12 left ventricular (LV) and 2 right ventricular (RV) segments. Regional and overall systolic function were calculated together with four indices of dyssynchrony.

Results There were no differences in regional or overall LV systolic function between groups, or in any of the four dyssynchrony indices. Peak systolic velocity (s′) was higher in the RV of ATH than in CON (9.7±1.5 vs 8.7±1.5 cm/s, p=0.004), but not after indexing by cardiac length (p=0.331). Strain was similar in ATH and CON in 8 of 12 LV myocardial segments. In septum and anteroseptum, basal and mid-ventricular s′ was 6–7% and 17–19% higher in ATH than in CON (p<0.05), respectively, while s′ was 12% higher in CON in the basal LV lateral wall (p=0.013). After indexing by cardiac length, s′ was only higher in ATH in the mid-ventricular septum (p=0.041).

Conclusions We found differences between trained and untrained females in segmental systolic myocardial function, but not in global measures of systolic function, including cardiac synchrony. These findings give new insights into cardiac adaptation to endurance training and could also be of use for sports cardiologists evaluating female athletes.

There are relatively few studies on female athletes examining cardiac size and function and how these measures relate to maximal oxygen uptake (VO2max ). When determining sports eligibility, it is important to know what physiological adaptations and characteristics may be expected in female athletes, taking body and cardiac size into account. The purposes of this study were (a) to compare right and left heart dimensions and function in female endurance athletes (ATH) and in non-athletic female controls of similar age (CON); and (b) to explore how these measures related to VO2max . Forty-six ATH and 48 CON underwent a maximal bicycle exercise test and an echocardiographic examination at rest, including standard and color tissue Doppler investigation. All heart dimensions indexed for body size were larger in ATH (all P < 0.01). The diastolic mitral E/A ratio was 27% higher in ATH (P < 0.001) while systolic left and right atrio-ventricular longitudinal displacement was 7% (P = 0.002) and 15% (P < 0.001) larger in ATH, respectively. Half (50.3%) of the variability in VO2max could be explained by left ventricular end-diastolic volume. Our results could be useful in evaluating female endurance athletes with suspected cardiac disease and contribute to understanding differences between female athletes and non-athletes.

Background. The increase in cardiac dimensions following endurance training is well acknowledged. A few studies report a larger inferior vena cava (IVC) in trained, predominatly male subjects while athlete-control studies upon females are lacking. Previous studies were constrained to long-axis measurements, and there are no reports in the literature on IVC short-axis dimensions and shape in athletes.

Methods and Results. Forty-eight sedentary and 46 endurance trained females (mean age 21±2 years, VO2max 39±5 vs. 52±5 mL×kg-1×min-1, p<0.001) underwent echocardiographic examination including IVC diameter and cross-sectional area measured in the subcostal view. IVC shape was calculated as the ratio of short-axis major-to-minor diameter.

Five out of eight IVC dimensions were larger in trained females, including maximal long-axis diameter (mean 24±3 vs. 20±3 mm, p<0.001) and maximal short-axis area (mean 5.5±1.5 vs. 4.7±1.4 cm2, p=0.022). Both groups presented with a slightly oval IVC with no differences between the groups in IVC shape or inspiratory decrease in any IVC dimension. The IVC long-axis diameter reflected the minor-axis diameter obtained in the short-axis view, during both expiration and inspiration. Positive correlations were seen between maximal IVC long-axis diameter and maximal oxygen uptake (r=0.52, p<0.01), left ventricular end-diastolic volume (r=0.46, p<0.01) and right atrial area (r=0.49, p<0.01).

Conclusion. The IVC was larger in endurance trained than in untrained females but showed similar shape and inspiratory decrease in dimensions. The long-axis IVC diameter was related to maximal oxygen uptake.

Objectives To examine whether intrauterine growth restriction (IUGR) is associated with increased cardiovascular risk later in life. Methods We examined 19 young adults (aged 2225 years) who were born at term after IUGR, along with 18 controls. All had been examined previously with fetal Doppler, and in the present follow-up with echocardiography, carotid echo-tracking ultrasound, applanation tonometry, blood pressure and laser Doppler, in order to characterize their cardiac and vascular geometry and/or function. Results The diameter of the ascending aorta and the left ventricular diameter were smaller in the IUGR group, but only ascending aortic diameter remained significantly smaller after adjustment for body surface area (Pandlt;0.05). The aortic pressure augmentation index was higher in the IUGR group (Pandlt;0.05). The common carotid artery diameter, intimamedia thickness and distensibility as well as left ventricular mass and function were similar in the two groups. IUGR status was found to be an independent predictor of ascending aortic diameter. Conclusions IUGR due to placental dysfunction seems to contribute to the higher systolic blood pressure augmentation and the smaller aortic dimensions that are observed in adults more than 20 years later, with possible negative consequences for future left ventricular performance due to increased aortic impedance.

Background

Anthropometric measurements are useful in clinical practice since they are non-invasive and cheap. Previous studies suggest that sagittal abdominal diameter (SAD) may be a better measure of visceral fat depots. The aim of this study was to prospectively explore and compare how laboratory and anthropometric risk markers predicted subclinical organ damage in 255 patients, with type 2 diabetes, after four years.

Methods

Baseline investigations were performed in 2006 and were repeated at follow-up in 2010. Carotid intima-media thickness (IMT) was evaluated by ultrasonography and aortic pulse wave velocity (PWV) was measured with applanation tonometry over the carotid and femoral arteries at baseline and at follow-up in a cohort of subjects with type 2 diabetes aged 55–65 years old.

Results

There were significant correlations between apolipoprotein B (apoB) (r = 0.144, p = 0.03), C - reactive protein (CRP) (r = 0.172, p = 0.009) at baseline and IMT measured at follow-up. After adjustment for sex, age, treatment with statins and Hba1c, the associations remained statistically significant. HbA1c, total cholesterol or LDL-cholesterol did not correlate to IMT at follow-up. Baseline body mass index (BMI) (r = 0.130, p = 0.049), waist circumference (WC) (r = 0.147, p = 0.027) and sagittal Abdominal Diameter (SAD) (r = 0.184, p = 0.007) correlated to PWV at follow-up. Challenged with sex, SBP and HbA1c, the association between SAD, not WC nor BMI, and PWV remained statistically significant (p = 0.036). In a stepwise linear regression, entering both SAD and WC, the association between SAD and PWV was stronger than the association between WC and PWV.

Conclusions

We conclude that apoB and CRP, but not LDL-cholesterol predicted subclinical atherosclerosis. Furthermore, SAD was more independent in predicting arterial stiffness over time, compared with WC, in middle-aged men and women with type 2 diabetes.

The normal aging process of the brachial artery (BA) wall is of specific interest since it is often selected as a model artery in studies of vascular function. With echo-tracking ultrasound, diameter, absolute diameter change, and intima-media thickness (IMT) were registered in 60 healthy subjects, 21-86 yr (30 men), at a proximal, upper third, and distal arterial site along the upper arm. Blood pressure was recorded noninvasively, and the distensibility coefficient (DC) was calculated. The diameter at the proximal site increased with age from 5.5 +/- 0.2 mm in the young subjects to 6.9 +/- 0.3 mm (P andlt; 0.01) in the elderly subjects, concomitantly as IMT increased from 0.40 +/- 0.01 to 0.65 +/- 0.03 mm (P andlt; 0.001). The diameter at the other sites was similar in the young and elderly subjects, whereas IMT increased slightly with age. At the proximal site, DC decreased dramatically from 40.7 +/- 2.2 to 10.1 +/- 0.8 10(-3)/kPa (P andlt; 0.001) with age, whereas hardly no change was seen in the distal upper arm. The principal transit zone between elastic to predominantly muscular artery behavior seems to be located within the proximal part of the brachial artery, emphasizing the importance of carefully defining the arterial examination site.

Observations of increased stiffness in the elastic aorta in women with diabetes, but not men, emphasise the need for further analysis regarding early abnormalities in arterial wall properties of women with type 1 diabetes mellitus (DM).

Ultrasound was used to study the wall properties of the distal brachial artery (BA) in 37 type 1 diabetic women (aged 22-45 years) without evident complications and in 53 controls (C). Blood samples were drawn for later analysis.

Flow-mediated dilatation (FMD) was slightly lower in DM than C, 8.1 +/- 4.3% vs. 10.3 +/- 4.9% (p&lt;0.05), and nitrate-mediated dilatation (NMD) was markedly lower, 21.7 +/- 6.6% vs. 31.4 +/- 5.7% (p&lt;0.001). Lumen diameter, intima-media thickness and distensibility were similar in DM and C. Insulin-like growth factor (IGF-1) was lower in DM than C, 231 +/- 65 vs. 349 +/- 68 ng/ml (p&lt;0.001). Glycosylated haemoglobin (HbA(1C)) and matrix metalloproteinase (MMP-9) were independent predictors of the reduced NMD in the DM.

Brachial artery responsiveness to an exogenous donor of nitric oxide (NO) was markedly reduced in type 1 diabetic women despite only limited reduction in endothelium-dependent dilatation. The negative association between NMD and HbA(1C) suggests that long-term hyperglycaemia impairs vascular smooth muscle cell function in DM.

The mechanical properties of the arterial wall are of great importance for blood pressure regulation and cardiac load. With increasing age, large arteries are affected by increased wall stiffness. Furthermore, atherosclerotic manifestations may increase the stiffness even further, both processes acting as independent cardiovascular risk factors affecting the arterial system in a heterogeneous way.

The aims of this thesis was to characterize the local mechanical properties of brachial artery (BA) with the aid of ultrasound technique and to evaluate the influence of 1) age, gender, sympathetic stimulation and examination site; 2) type 1 diabetes (DM) and its association to circulatory biomarkers; and 3) to evaluate the general properties of the arterial system with the aid of pulse wave velocity (PWV) as well as pulse wave analysis (PWA) in systemic lupus erythematosus (SLE) and correlate the findings to disease activity and circulatory biomarkers.

In the most proximal arterial segment of the upper arm a pronounced age-related decrease in wall distensibility, increase in intima-media thickness (IMT), and a slight increase in diameter were seen. Sympathetic stimulation had no influence on wall mechanics. More distally in BA, no change in diameter, and only minor increase in IMT and decrease in distensibility were seen. No gender differences were found. These findings suggest that the principle transit zone between elastic and muscular artery behaviour is located in the proximal part of the upper arm.

Women with uncomplicated insulin-dependent DM had similar diameter, IMT and distensibility in their distal BA as controls, whereas flow-mediated dilatation (FMD) was slightly, and nitrate mediated dilatation (NMD) markedly reduced. NMD was negatively correlated with higher HbA1c levels. Vascular smooth muscle cell function seems to be an early manifestation of vascular disease in women with DM, influenced by long-term hyperglycaemia.

Women with SLE had increased aortic PWV compared to controls, a finding positively associated with increased levels of complement factor 3 (C3), but not with disease activity. The increased stiffness of central arteries may be one factor contributing to the increased cardiovascular risk seen in SLE.

Systemic lupus erythematosus (SLE) is a connective tissue disease where inflammatory activity affects several organ systems. An increased risk of cardiovascular disease has been identified in these patients, even after correction for traditional risk factors. The aim of the present study was to evaluate arterial stiffness and central hemodynamics in women with SLE in comparison to controls.

Arterial tonometry was used to measure aortic (carotid-femoral) and arm (carotid-radial) pulse wave velocity (PWV), reflected pressure waves, and aortic augmentation index (AIx) in 27 women with SLE (52 to 68 years) and 27 controls. Aortic PWV was higher in women with SLE than controls, 9.8 m/s versus 8.2 m/s (P 0.01), after correction for mean arterial pressure and body mass index, 9.5 m/s versus 8.5 m/s (P 0.05). Other parameters were similar, arm PWV, 8.4 versus 8.5 m/s, AIx 34 versus 33% and calculated central aortic pulse pressure 48 versus 43 mmHg, in SLE and controls, respectively (NS). Aortic PWV was positively associated to C-reactive protein (CRP) and complement factor 3 (C3).

Women with SLE have increased stiffness of their elastic central arteries. This may be one factor contributing to the increased cardiovascular risk seen in this cohort.

Aims: The mechanical properties of arteries play a major role in the regulation of blood pressure and cardiac performance. The effect of sympathetic stimulation on the mechanical properties of the proximal brachial artery was analysed in 18 healthy volunteers, nine young (25 ± 2 years) and nine elderly (69 ± 2 years).

Methods: A non-invasive ultrasonic echo-tracking system for measurement of systolic/diastolic variation of the proximal brachial artery diameter in combination with intra-arterial pressure measurements was used to determine wall mechanics. The pressure–diameter (P–D) relationship, distensibility coefficient (DC), compliance coefficient (CC) and stiffness(β) were obtained at rest and during sympathetic stimulation induced by lower body negative pressure (LBNP).

Results: The peripheral vascular resistance increased by 100 and 72%, respectively in the young and elderly during LBNP (P < 0.001). Simultaneously, the mechanical properties of the proximal brachial artery remained unaltered, as estimated from both P–D relationship and stiffness in young (β-index rest: 5.2 ± 0.9, LBNP: 5.5 ± 1.3, NS) as well as elderly (β-index rest: 13.6 ± 4.6, LBNP: 16.1 ± 4.7, NS).

Conclusions: LBNP-induced sympathetic activation does not change proximal brachial artery mechanics, in contrast to earlier reports on the muscular distal brachial artery. This may imply that the transition between elastic and muscular artery behaviour is within the length of the brachial artery, where the site of transition from elastic to muscular wall structure needs to be specified in future studies.

Objective: The popliteal artery is, after the aorta, the most common site for aneurysm formation. Why the popliteal artery is more susceptible than other peripheral muscular arteries is unknown. An important factor may be differences in arterial wall composition as compared with other peripheral muscular arteries, which in turn affect wall properties. These are however unknown. We studied the mechanical wall properties of the popliteal artery in healthy subjects. Material and Methods: An ultrasound echo-tracking system was used to measure pulsatile changes in popliteal diameter in 108 healthy subjects (56 female, 52 male, age range, 9-82 years). In combination with blood pressure, stiffness (β), strain, cross-sectional artery wall compliance coefficient (CC), and distensibility coefficient (DC) were calculated. Intima-media thickness (IMT) was registered with a Philips P700 ultrasound scanner. Results: The popliteal diameter increased with age, and was larger in male subjects than in female subjects (P < .001). Fractional diameter change (strain) decreased with age (P < .001), and strain values were lower in male subjects than in female subjects (P < .01). Accordingly, stiffness increased with age (P < .001), with higher stiffness values in male subjects (P < .01). DC decreased with age (P < .001), with lower DC values in male subjects (P < .01). CC decreased with age, with no difference between genders (P < .001). IMT increased with age (P < .001), with higher IMT values in male subjects (P < .001). The increase in IMT did not affect distensibility. Conclusion: The wall properties of the popliteal artery are affected by age and gender, not only with an increase in diameter, but also with an age-related decrease in distensibility, with male subjects having lower distensibility than in female subjects. This seems not to be the behavior of a true muscular artery, but of a central elastic artery, such as the aorta, and might have implications for susceptibility to arterial dilatation, as well as the association of aneurysm formation between the aorta and the popliteal artery.

With increasing age, the diameter of central elastic arteries increases, whereas their distensibility decreases. The purpose of this study was to investigate the mechanical properties of the proximal brachial artery in relation to age and gender. Distensibility coefficient (DC), stiffness and compliance coefficient (CC) were calculated in 136 healthy males and females (range 9-82 y) using echo-tracking sonography. CC decreased with age in both genders, but CC was higher in males. Stiffness increased and DC decreased with age in an exponential manner, without any differences between genders. In conclusion, as in central elastic arteries, the distensibility of the proximal brachial artery decreases with age, in contrast to earlier reports on the muscular distal brachial artery. This may imply that the transition between elastic and muscular artery behavior is within the length of the brachial artery. In future studies using the brachial artery, the examination site needs to be defined.

Aim: The aim of this study was to prospectively explore how laboratory and anthropometric risk factors predicted subclinical organ damage in 255 patients, with type 2 diabetes, after four years.

Methods: Baseline investigations were performed in 2006 and were repeated at follow-up in 2010. Carotid intima-media thickness (IMT) was evaluated by ultrasonography and aortic pulse wave velocity (PWV) was measured with applanation tonometry over the carotid and femoral arteries at baseline and at follow-up in a cohort of subjects with type 2 diabetes aged 55-65 years old.

Results: There were significant correlations between apolipoprotein B (apoB) (r= 0.144, p=0.03), C - reactive protein (CRP) (r=0.172, p=0.009) at baseline and IMT measured at follow-up. After adjustment for sex, age, treatment with statins and Hba1c, the associations remained statistically significant. HbA1c, total cholesterol or LDL-cholesterol did not correlate to IMT at follow-up. Baseline body mass index (BMI) (r=0.130, p=0.049), waist circumference (WC) (r=0.147, p=0.027) and sagittal Abdominal Diameter (SAD) (r=0.184, p=0.007) correlated to PWV at follow-up. Challenged with sex, SBP and HbA1c, the association between SAD, not WC nor BMI, and PWV remained statistically significant (p=0.036). In a stepwise linear regression, entering both SAD and WC, the association between SAD and PWV was stronger than the association between WC and PWV.

Conclusion: We conclude that apoB and CRP, but not LDL-cholesterol predicted subclinical atherosclerosis. Furthermore, SAD was more independent in predicting arterial stiffness over time, compared with WC, in middle-aged men and women with type 2 diabetes.