Normal aortic dimensions and flow in 168 children and young adults

Background: Knowledge of normal aortic dimensions is important while evaluating children with aortic root dilatation. Objective: The purpose of the study was to create normal values for aortic dimensions with two‐dimensional echocardiography and for aortic flow velocities with Doppler echocardiography in healthy children and young adults. Design and patients: One hundred and sixty‐eight healthy children were studied by a single observer using digitized two‐dimensional (2DE) and Doppler echocardiography. Methods: The 2DE measurements were obtained at the level of aortic annulus, sinus, sinotubular junction, before the origin of innominate artery, before and after the origin of left carotid artery, after left subclavian artery and descending aorta at the level of the diaphragm. Doppler measurements were made from ascending aorta and from descending aorta. Results: For the analysis the subjects were divided into five groups according to body surface area (BSA): 0·5–0·75 m², 0·75–1·0 m², 1·0–1·25 m², 1·25–1·5 m² and over 1·5 m². Aortic dimensions normalized to BSA were greater in smaller children at all levels. All diameters correlated closely with age, BSA, height and weight (for each r>0·75, P<0·001). The best predictor of aortic dimensions was BSA with r values over 0·84 for all estimates (P<0·001). The diameters of ascending and descending aorta were similar in both genders when indexed to BSA. Flow velocities in descending aorta were greater than those measured in ascending aorta (P<0·001 for all measurements). There were significant inverse correlations with heart rate and velocity time integral in ascending and descending aorta (r = ?0·32 and ?0·53, P<0·001, respectively). Conclusions: The presented aortic dimensions at eight levels from the valve annulus to the descending thoracic aorta by 2DE in conjunction with Doppler measurements of ascending and descending aorta in 168 healthy subjects will serve as reference data for further studies and clinical use in patients with various cardiac abnormalities.     

Consistency of aortic distensibility and pulse wave velocity estimates with respect to the Bramwell-Hill theoretical model: a cardiovascular magnetic resonance study

Background

Arterial stiffness is considered as an independent predictor of cardiovascular mortality, and is increasingly used in clinical practice. This study aimed at evaluating the consistency of the automated estimation of regional and local aortic stiffness indices from cardiovascular magnetic resonance (CMR) data.

Results

Forty-six healthy subjects underwent carotid-femoral pulse wave velocity measurements (CF_PWV) by applanation tonometry and CMR with steady-state free-precession and phase contrast acquisitions at the level of the aortic arch. These data were used for the automated evaluation of the aortic arch pulse wave velocity (Arch_PWV), and the ascending aorta distensibility (AA_Distc, AA_Distb), which were estimated from ascending aorta strain (AA_Strain) combined with either carotid or brachial pulse pressure. The local ascending aorta pulse wave velocity AA_PWVc and AA_PWVb were estimated respectively from these carotid and brachial derived distensibility indices according to the Bramwell-Hill theoretical model, and were compared with the Arch_PWV. In addition, a reproducibility analysis of AA_PWV measurement and its comparison with the standard CF_PWV was performed. Characterization according to the Bramwell-Hill equation resulted in good correlations between Arch_PWV and both local distensibility indices AA_Distc (r = 0.71, p < 0.001) and AA_Distb (r = 0.60, p < 0.001); and between Arch_PWV and both theoretical local indices AA_PWVc (r = 0.78, p < 0.001) and AA_PWVb (r = 0.78, p < 0.001). Furthermore, the Arch_PWV was well related to CF_PWV (r = 0.69, p < 0.001) and its estimation was highly reproducible (inter-operator variability: 7.1%).

Conclusions

The present work confirmed the consistency and robustness of the regional index Arch_PWV and the local indices AA_Distc and AA_Distb according to the theoretical model, as well as to the well established measurement of CF_PWV, demonstrating the relevance of the regional and local CMR indices.     

Magnetic resonance assessment of aortic pulse wave velocity, aortic distensibility, and cardiac function in uncomplicated type 2 diabetes mellitus.

BACKGROUND: Type 2 diabetes mellitus (DM2) may augment arterial stiffening and thereby modulates left ventricular (LV) function. Cardiovascular magnetic resonance (CMR) is well suited to assess aortic pulse wave velocity (PWV) and aortic distensibility, both markers of arterial stiffness, without the use of geometric assumptions. Furthermore, CMR is a reliable method for assessing left ventricular (LV) function. The purpose of this study was to assess LV function, PWV, and aortic distensibility in patients with DM2 using MR. METHODS: Fourteen patients with well controlled, uncomplicated DM2, and 16 age and gender matched healthy subjects were included. PWV was calculated based on MR velocity mapping at two predefined aortic locations. Aortic distensibility was measured in the mid ascending aorta. LV volumes were measured by fast gradient-echo imaging to assess systolic function. Furthermore, mitral inflow was measured by MR velocity mapping to assess diastolic LV function. RESULTS: Mean PWV was higher in patients as compared to healthy subjects (6.83 +/- 1.60 m/s vs. 5.65 +/- 0.75 m/s, p < 0.05). This difference was independent of blood pressure. PWV correlated significantly (p < 0.05) with fasting plasma glucose and insulin levels. Aortic distensibility was lower in patients as compared to healthy subjects (4.50 x 10(- 3)+/- 2.24 x 10(- 3) mmHg(- 1) vs. 7.42 x 10(- 3)+/- 3.34 x 10(- 3) mmHg(- 1), p < 0.05). Distensibility correlated negatively with PWV and positively with LV diastolic function (p < 0.05). CONCLUSION: A combined CMR assessment of aortic PWV, aortic distensibility, and heart function reveals abnormal PWV and distensibility in patients with DM2, independent of blood pressure. Furthermore, aortic distensibility correlates with diastolic left ventricular function.     

Gait performance in relation to aortic pulse wave velocity,carotid artery elasticity and peripheral perfusion in healthy older adults

Arterial stiffening is a widely known physiological change that occurs with ageing, but the functional consequences of vascular ageing are unclear. The purpose of this study was to determine whether carotid–femoral pulse wave velocity (PWV), mechanical properties of the carotid and femoral arteries and/or peripheral perfusion was associated with gait performance measured using a 400‐m walk test. Twenty‐one healthy older (68 ± 5 years) adults without cardiovascular disease participated in this study. Applanation tonometry was used to measure PWV, and Doppler ultrasound was used to measure arterial wall properties of the left common carotid and common femoral artery along with femoral blood flow. The median walk distance in the first 2 min of the test was 585 ft, and the overall gait speed was 1·5 m s^?1. Gait performance was inversely correlated with PWV (distance: r = ‐0·51; speed: r = ?0·48; P<0·05) and carotid artery stiffness index β (distance: r = ?0·56; speed: r =  ? 0·51; P<0·05) after adjustment for age, body mass index, waist circumference and systolic blood pressure. No significant correlations were found between gait performance and femoral artery stiffness index β or femoral artery blood flow. These results found higher central arterial stiffness, as assessed by segmental arterial stiffness or local arterial wall properties, is associated with lower gait performance in older adults independent of other confounders.     

Association of thyrotropin with arterial pulse wave velocity in young adults: The Cardiovascular Risk in Young Finns Study

Abstract

Objective. Limited data are available regarding the relationship of thyrotropin (TSH) and arterial pulse wave velocity (PWV) at population level. Therefore, we conducted the present study to determine whether TSH is related to PWV assessed in young adulthood. Methods. The study population consisted of 1598 Finnish white young adults (aged 30–45 years, 47.4% males) who had TSH, traditional cardiovascular risk factors, and PWV measured in 2007. PWV measurements were performed using a whole-body impedance cardiography device. Results. In bivariate association analyses, TSH level was significantly associated with body mass index (BMI), smoking, diastolic blood pressure, triglyceride and insulin levels (p < 0.001). In multivariable regression model, TSH (β = 0.055, p = 0.015) was associated with PWV when adjusted with age (β = 0.295, p < 0.001) and sex (β = 0.345, p < 0.001). The association of TSH with PWV was however diluted to non-significant after further adjustment with traditional risk factors (β = 0.027, p = 0.218 for TSH). Conclusion. Serum TSH was associated with PWV on population level when adjusted with age and sex. This association was diluted when cardiovascular risk factors were added in the model, suggesting that the association of thyroid hormone on arterial stiffening is not independent of changes in the traditional risk factor levels.     

Normal values for cardiovascular magnetic resonance in adults and children

Morphological and functional parameters such as chamber size and function, aortic diameters and distensibility, flow and T1 and T2* relaxation time can be assessed and quantified by cardiovascular magnetic resonance (CMR). Knowledge of normal values for quantitative CMR is crucial to interpretation of results and to distinguish normal from disease. In this review, we present normal reference values for morphological and functional CMR parameters of the cardiovascular system based on the peer-reviewed literature and current CMR techniques and sequences.

Electronic supplementary material

The online version of this article (doi:10.1186/s12968-015-0111-7) contains supplementary material, which is available to authorized users.     

Comparison of echotracking and magnetic resonance assessment of abdominal aorta distensibility and relationships with pulse wave velocity

Arterial distensibility can be measured either by echotracking or by nuclear magnetic resonance (MRI). Little information, however, is available on the comparison between the two methods and on the relationships between the results obtained with the two approaches and the arterial stiffness gold standard measurement, i.e., pulse wave velocity (PWV). In 28 normotensive subjects (age 33.0 ± 10.4 years, mean ± SD) we measured aortic diameter 1 cm above iliac bifurcation, aortic pulse pressure by tonometry and calculated arterial distensibility via the Reneman formulae for both methods. Aortic diameter and aortic distensibility were not superimposable and higher values were systematically detected with the MRI approach than with the ultrasound one. However, PWV showed a significant correlation with aortic distensibility values obtained by both methods (r = 0.50 and r = 0.49, p < 0.05). These data provide evidence that MRI-measured distensibility value is higher than that obtained via echotracking. The significant correlation with PWV, however, suggests that both methods can be regarded as valuable approaches. Considering the greater economic cost and the lower availability in daily clinical and research practice of MRI, echotracking ultrasonography can be regarded as a reliable and feasible method to assess aortic distensibility.     

Site-specific association between distal aortic pulse wave velocity and peripheral arterial stenosis severity: a prospective cardiovascular magnetic resonance study

Background

Vascular disease expression in one location may not be representative for disease severity in other vascular territories, however, strong correlation between disease expression and severity within the same vascular segment may be expected. Therefore, we hypothesized that aortic stiffening is more strongly associated with disease expression in a vascular territory directly linked to that aortic segment rather than in a more remote segment. We prospectively compared the association between aortic wall stiffness, expressed by pulse wave velocity (PWV), sampled in the distal aorta, with the severity of peripheral arterial occlusive disease (PAOD) as compared to atherosclerotic markers sampled in remote vascular territories such as PWV in the proximal aorta and the normalized wall index (NWI), representing the vessel wall thickness, of the left common carotid artery.

Methods

Forty-two patients (23 men; mean age 64±10 years) underwent velocity-encoded cardiovascular magnetic resonance (CMR) in the proximal and distal aorta, whole-body contrast-enhanced MR angiography (CE-MRA) and carotid vessel wall imaging with black-blood CMR in the work-up for PAOD. Strength of associations between aortic stiffness, carotid NWI and peripheral vascular stenosis grade were assessed and evaluated with multiple linear regression.

Results

Stenosis severity correlated well with PWV in the distal aorta (Pearson r_P=0.64, p<0.001, Spearman r_S=0.65, p<0.001) but to a lesser extent with PWV in the proximal aorta (r_P=0.48, p=0.002, r_S=0.22, p=0.18). Carotid NWI was not associated with peripheral stenosis severity (r_P=0.17, p=0.28, r_S=0.14, p=0.37) nor with PWV in the proximal aorta (r_P=0.22, p=0.17) nor in the distal aorta (r_P=0.21, p=0.18). Correlation between stenosis severity and distal aortic PWV remained statistically significant after correction for age and gender.

Conclusions

Distal aortic wall stiffness is more directly related to peripheral arterial stenosis severity than markers from more remote vascular territories such as proximal aortic wall stiffness or carotid arterial wall thickness. Site-specific evaluation of vascular disease may be required for full vascular risk estimation.     

Correlations between Arteriograph-derived pulse wave velocity and aortic elastic properties by echocardiography

Introduction: There is an increased scientific interest on the evaluation of parameters characterizing aortic elasticity. The current study was designed to compare two characteristics of aortic distensibility: Arteriograph‐derived pulse wave velocity (PWV) and augmentation index standardized to 80 per minutes heart rate (AIx80) and aortic elastic properties by echocardiography. Methods: The study comprised 21 adult healthy volunteers. In all cases, systolic and diastolic ascending aortic diameters were recorded during transthoracic echocardiography in M‐mode at a level 3 cm above the aortic valve from a parasternal long‐axis view. Using forearm blood pressure values, the following aortic elastic properties were calculated: aortic strain, distensibility and stiffness index. All patients were examined by Arteriograph at the same time, as well. Results: The Arteriograph‐derived AIx80 and PWV correlated with aortic strain (R = ?0·495, P = 0·023 and R = ?0·527, P = 0·014, respectively) and aortic stiffness index (R = 0·454, P = 0·039 and R = 0·608, P = 0·003, respectively). Aortic distensibility did not correlated with AIx80 (R = ?0·344, P = 0·127), only with PWV (R = ?0·593, P = 0·005, respectively). Discussion: Low to moderate correlations could be demonstrated between Arteriograph‐derived PWV and aortic elastic properties by echocardiography.     

Measuring aortic pulse wave velocity using high-field cardiovascular magnetic resonance: comparison of techniques

Background

The assessment of arterial stiffness is increasingly used for evaluating patients with different cardiovascular diseases as the mechanical properties of major arteries are often altered. Aortic stiffness can be noninvasively estimated by measuring pulse wave velocity (PWV). Several methods have been proposed for measuring PWV using velocity-encoded cardiovascular magnetic resonance (CMR), including transit-time (TT), flow-area (QA), and cross-correlation (XC) methods. However, assessment and comparison of these techniques at high field strength has not yet been performed. In this work, the TT, QA, and XC techniques were clinically tested at 3 Tesla and compared to each other.

Methods

Fifty cardiovascular patients and six volunteers were scanned to acquire the necessary images. The six volunteer scans were performed twice to test inter-scan reproducibility. Patient images were analyzed using the TT, XC, and QA methods to determine PWV. Two observers analyzed the images to determine inter-observer and intra-observer variabilities. The PWV measurements by the three methods were compared to each other to test inter-method variability. To illustrate the importance of PWV using CMR, the degree of aortic stiffness was assessed using PWV and related to LV dysfunction in five patients with diastolic heart failure patients and five matched volunteers.

Results

The inter-observer and intra-observer variability results showed no bias between the different techniques. The TT and XC results were more reproducible than the QA; the mean (SD) inter-observer/intra-observer PWV differences were -0.12(1.3)/-0.04(0.4) for TT, 0.2(1.3)/0.09(0.9) for XC, and 0.6(1.6)/0.2(1.4) m/s for QA methods, respectively. The correlation coefficients (r) for the inter-observer/intra-observer comparisons were 0.94/0.99, 0.88/0.94, and 0.83/0.92 for the TT, XC, and QA methods, respectively. The inter-scan reproducibility results showed low variability between the repeated scans (mean (SD) PWV difference = -0.02(0.4) m/s and r = 0.96). The inter-method variability results showed strong correlation between the TT and XC measurements, but less correlation with QA: r = 0.95, 0.87, and 0.89, and mean (SD) PWV differences = -0.12(1.0), 0.8(1.7), and 0.65(1.6) m/s for TT-XC, TT-QA, and XC-QA, respectively. Finally, in the group of diastolic heart failure patient, PWV was significantly higher (6.3 ± 1.9 m/s) than in volunteers (3.5 ± 1.4 m/s), and the degree of LV diastolic dysfunction showed good correlation with aortic PWV.

Conclusions

In conclusion, while each of the studied methods has its own advantages and disadvantages, at high field strength, the TT and XC methods result in closer and more reproducible aortic PWV measurements, and the associated image processing requires less user interaction, than in the QA method. The choice of the analysis technique depends on the vessel segment geometry and available image quality.     

Bramwell-Hill modeling for local aortic pulse wave velocity estimation: a validation study with velocity-encoded cardiovascular magnetic resonance and invasive pressure assessment

Background

The Bramwell-Hill model describes the relation between vascular wall stiffness expressed in aortic distensibility and the pulse wave velocity (PWV), which is the propagation speed of the systolic pressure wave through the aorta. The main objective of this study was to test the validity of this model locally in the aorta by using PWV-assessments based on in-plane velocity-encoded cardiovascular magnetic resonance (CMR), with invasive pressure measurements serving as the gold standard.

Methods

Seventeen patients (14 male, 3 female, mean age ± standard deviation = 57 ± 9 years) awaiting cardiac catheterization were prospectively included. During catheterization, intra-arterial pressure measurements were obtained in the aorta at multiple locations 5.8 cm apart. PWV was determined regionally over the aortic arch and locally in the proximal descending aorta. Subsequently, patients underwent a CMR examination to measure aortic PWV and aortic distention. Distensibility was determined locally from the aortic distension at the proximal descending aorta and the pulse pressure measured invasively during catheterization and non-invasively from brachial cuff-assessment. PWV was determined regionally in the aortic arch using through-plane and in-plane velocity-encoded CMR, and locally at the proximal descending aorta using in-plane velocity-encoded CMR. Validity of the Bramwell-Hill model was tested by evaluating associations between distensibility and PWV. Also, theoretical PWV was calculated from distensibility measurements and compared with pressure-assessed PWV.

Results

In-plane velocity-encoded CMR provides stronger correlation (p = 0.02) between CMR and pressure-assessed PWV than through-plane velocity-encoded CMR (r = 0.69 versus r = 0.26), with a non-significant mean error of 0.2 ± 1.6 m/s for in-plane versus a significant (p = 0.006) error of 1.3 ± 1.7 m/s for through-plane velocity-encoded CMR. The Bramwell-Hill model shows a significantly (p = 0.01) stronger association between distensibility and PWV for local assessment (r = 0.8) than for regional assessment (r = 0.7), both for CMR and for pressure-assessed PWV. Theoretical PWV is strongly correlated (r = 0.8) with pressure-assessed PWV, with a statistically significant (p = 0.04) mean underestimation of 0.6 ± 1.1 m/s. This theoretical PWV-estimation is more accurate when invasively-assessed pulse pressure is used instead of brachial cuff-assessment (p = 0.03).

Conclusions

CMR with in-plane velocity-encoding is the optimal approach for studying Bramwell-Hill associations between local PWV and aortic distensibility. This approach enables non-invasive estimation of local pulse pressure and distensibility.     

Pulse wave velocity reference values in healthy adults aged 26-75 years

The stiffening of arteries is associated with various cardiovascular diseases. Arterial stiffening can be studied utilizing arterial pulse wave velocity (PWV), but the absence of reliable reference values for PWV has limited its use in clinical practice. The aim of this study was to establish a range of reference values for PWV. PWV was examined by measuring the time difference of systolic pulse waves in arteries from the aortic arch to the popliteal artery using whole-body impedance cardiography (ICG). The study population consisted of 799 individuals (age range 25-76 years), 283 of whom had no evidence of cardiovascular disease, and a low burden of risk factors was selected to represent an apparently healthy population. In healthy study population, PWV was higher in males (8 x 9 +/- 1 x 8 m s(-1)) than females (8 x 1 +/- 2 x 0 m s(-1), P<0 x 001). Young males had lower PWV values than old males. Correspondingly, young females also had lower PWV values than old females. PWV was clearly associated with age, and PWV was higher in young and middle-aged males than in females. There was no statistically significant difference between old males and females in PWV. In conclusion, whole-body ICG provides a practical method for PWV measurement. Reference values can be useful in the clinical management of patients, especially in detecting early vascular disease or an increased risk of cardiovascular complications.     

Obese children show increased intimal wall thickness and decreased pulse wave velocity

Objective: Childhood obesity confers an increased risk of vascular changes and adult cardiovascular disease. Using a high‐resolution ultrasound technique that enables separation of intimal and medial layers, we examined the intimal thickness (IT) and intimal–medial thickness (IMT) of radial (RA) and dorsal pedal (DPA) arteries and the pulse wave velocity (PWV) in overweight/obese children and adolescents and in healthy subjects. Methods and results: IT and IMT of RA and DPA and PWV were measured in 33 obese children and adolescents (13·9 ± 1·6 years) and in 18 matched lean controls (14·3 ± 2·2). Increased RA IT was found in the obese group, whereas no differences in RA IMT or medial thickness were observed. Obese females accounted for the entire difference in RA IT (P = 0·04). DPA IT was inversely correlated with HDL cholesterol in the obese group (?0·56, P = 0·0089). PWV was lower in the obese group than in the lean group (6·2 ± 0·8 versus 7·0 ± 0·9 m s^?1, respectively; P = 0·001). Conclusions: Obese children and adolescents, primarily females, present with increased RA IT. The decreased PWV in the obese versus lean subjects might reflect general vasodilatation.     

Carotid arterial stiffness as a surrogate for aortic stiffness: relationship between carotid artery pressure-strain elastic modulus and aortic pulse wave velocity.

Common carotid arterial (CCA) stiffness can be assessed during carotid ultrasonography, but its association with aortic stiffness, a well-defined cardiovascular risk factor, has not been clarified. This study examines the relationship between CCA and aortic stiffness. CCA pressure-strain elastic modulus (Ep) and aortic pulse wave velocity (APWV) were evaluated in 110 healthy volunteers (age 56.2 +/- 14.6 y) by B-mode and Doppler ultrasonography. CCA Ep increased linearly with age and was higher in men than in women (model r2 = 0.50, p < 0.001). APWV increased quadratically with age (model r2 = 0.54, p < 0.001), similarly for women and men. Both CCA Ep and APWV were linearly associated with systolic blood pressure (BP) (r = 0.53 and 0.46, respectively) but not with diastolic BP. A linear relationship was found between CCA Ep and APWV (APWV = 194.7 + 5.67 x Ep [model r2 = 0.42, p < 0.001]). CCA Ep was associated with APWV (p < 0.001) independent of age, gender, and BP (model r2 = 0.62, p < 0.001), and the most parsimonious model to explain APWV included CCA Ep and age (APWV = 601.73 - 15.64 x age + 0.223 x age2 + 2.69 x Ep [model r2 = 0.60, p < 0.001]). Thus, CCA Ep is moderately associated with APWV. CCA stiffness as assessed by B-mode may be useful as a surrogate for aortic stiffness.     

Measurement of pulse wave velocity using pulse wave Doppler ultrasound: comparison with arterial tonometry

Pulse wave velocity (PWV), the speed of propagation of arterial pressure waves through the arterial tree, is related to arterial stiffness and is an important prognostic marker for cardiovascular events. In clinical practice PWV is commonly determined by arterial tonometry, with a noninvasive pressure sensor applied sequentially over carotid and femoral arteries. The electrocardiogram (ECG) is used as a timing reference to determine the time delay or "transit time" between the upstroke of carotid and femoral pulse waveforms. Commercially available vascular ultrasound scanners provide a pulsed wave (PW) Doppler velocity signal, which should allow determination of carotid-femoral transit time and hence PWV. We compared carotid-femoral PWV measured by tonometry and by PW Doppler ultrasound (Seimens, Apsen scanner with 7 MHz linear transducer) in asymptomatic subjects (n = 62, 26 male, aged 21 to 72 y). To test for intra-subject and inter-observer variation, ten subjects were scanned by one observer on two occasions 2 wk apart and by two observers on same day. PWV by tonometry ranged from 5.3 to 15.0 m/s. There was no significant difference between mean values of PWV obtained by the two techniques (mean difference: 0.3 m/s, standard deviation of difference: 1.5 m/s), which were closely correlated (r = 0.83). The coefficient of variation for repeated measures on the same subject by the same observer was 10.1% and the inter-observer coefficient of variation was 5.8%. These results suggest a commercial ultrasound scanner can be used to measure PWV, giving results that are reproducible and closely correlated with those obtained by arterial tonometry. (E-mail: ben_yu.jiang@kcl.ac.uk).     

12周有氧运动训练对老年人胘踝脉搏波速度的影响

目的通过随机对照研究观察12周有氧运动训练对缺乏锻炼习惯的老年人肱踝脉搏波速度（baPWV）的影响,探讨有氧运动训练对动脉功能的改善作用。 方法将符合入选标准的35例平均年龄为74.7岁的老年人分为运动组17例和对照组18例。运动组进行运动强度渐进性增加的有氧运动训练,每周3次,共12周;对照组不参加运动训练计划,只作对照的项目测定。2组均在训练计划开始前及结束时测定心率、血压和baPWV。 结果运动组baPWV在有氧训练后出现明显降低,平均值从（15.88±1.67）m/s降为（14.63±1.83）m/s（P<0.05）,同时伴有收缩压和舒张压的降低。对照组各项指标在12周的随访期间没有显著变化。 结论短期运动强度渐进性增加的有氧运动训练有助于改善缺乏良好运动习惯老年人的动脉弹性。     

极速脉搏波技术定量评价健康成人颈动脉弹性的研究

目的探讨极速脉搏波技术评价健康成人颈动脉弹性的参数及影响因素。方法健康体检志愿者128例,按年龄分为5组:20~29岁组(n=34),30~39岁组(n=22),40~49岁组(n=16),50~59岁组(n=36),≥60岁组(n=20)。灰阶超声测量颈动脉内-中膜厚度(IMT)。极速脉搏波技术测量颈动脉弹性参数,包括收缩期开始时的脉搏波传导速度(PWVBS)和收缩期结束时的脉搏波传导速度(PWVES)。比较IMT、PWVBS及PWVES在两侧颈总动脉、不同性别组及不同年龄组之间的差异,分析PWVBS、PWVES与IMT的相关性。其中30例受检者分别经两名医师检测,比较不同操作者对同一组受检者颈动脉弹性参数的差异。结果 IMT、PWVBS、PWVES在两侧颈动脉及不同性别组间差异无统计学意义。随着年龄的增加,颈动脉PWVBS和PWVES逐渐升高。PWVBS和PWVES与IMT呈正相关(r=0.236、0.462)。不同操作者检测同一组受检者的颈动脉弹性参数差异无统计学意义(P=0.899)。结论极速脉搏波技术能快速、直接测量局部血管弹性参数PWVBS和PWVES,为临床早期准确评价动脉弹性提供了新的手段。