Direct Determination rather than Oscillometric Estimation of Systolic Blood Pressure in Patients with Severe Chronic Kidney Disease.

INTRODUCTION: Although arterial hypertension is a major concern in patients with chronic kidney disease (CKD), obtaining accurate systolic blood pressure (SBP) measurement is challenging in this population for whom automatic oscillometric devices may yield erroneous results. METHODS: This cross-sectional study was conducted in 89 patients with stages 4, 5, and 5D CKD, for whom we compared SBP values obtained by the recently described systolic foot-to-apex time interval (SFATI) technique which provides direct SBP determination, the standard technique (Korotkoff sounds), and oscillometry. We investigated the effects of age, sex, diabetes, CKD stage, and pulse pressure to explain measurement errors defined as biases or misclassification relative to the SBP thresholds of 110-130-mm Hg. RESULTS: All 3 techniques showed satisfactory reproducibility for SBP measurement (CCC > 0.84 and >0.91, respectively, in dialyzed and nondialyzed patients). The mean ± SD from SBP as determined via Korotkoff sounds was 1.7 ± 4.6 mm Hg for SFATI (CCC = 0.98) and 5.9 ± 9.3 mm Hg for oscillometry (CCC = 0.88). Referring to the 110-130-mm Hg SBP range outside which treatment prescription or adaptation is recommended for CKD patients, SFATI underestimated SBP in 3 patients and overestimated it in 1, whereas oscillometry underestimated SBP in 12 patients and overestimated it in 3. Higher pulse pressure was the main explanatory factor for measurement and classification errors. DISCUSSION/CONCLUSION: SFATI provides accurate SBP measurements in patients with severe CKD and paves the way for the standardization of automated noninvasive blood pressure measurement devices. Before prescribing or adjusting antihypertensive therapy, physicians should be aware of the risk of misclassification when using oscillometry.

Comparative incidence of a first thrombotic event in purely obstetric antiphospholipid syndrome with pregnancy loss: the NOH-APS observational study.

The incidence of thrombosis in the purely obstetric form of antiphospholipid syndrome is uncertain. We performed a 10-year observational study of 1592 nonthrombotic women who had experienced 3 consecutive spontaneous abortions before the 10th week of gestation or 1 fetal death at or beyond the 10th week of gestation. We compared the frequencies of thrombotic events among women positive for antiphospholipid Abs (n = 517), women carrying the F5 6025 or F2 rs1799963 polymorphism (n = 279), and women with negative thrombophilia screening results (n = 796). The annual rates of deep vein thrombosis (1.46%; range, 1.15%-1.82%), pulmonary embolism (0.43%; range, 0.26%-0.66%), superficial vein thrombosis (0.44%; range, 0.28%-0.68%), and cerebrovascular events (0.32%; range, 0.18%-0.53%) were significantly higher in aPLAbs women than in the other groups despite low-dose aspirin primary prophylaxis. Women carrying 1 of the 2 polymorphisms did not experience more thrombotic events than women who screened negative for thrombophilia. Lupus anticoagulant was a risk factor for unprovoked proximal and distal deep and superficial vein thrombosis and women in the upper quartile of lupus anticoagulant activity had the highest risk. Despite data suggesting that aPLAbs may induce pregnancy loss through nonthrombotic mechanisms, women with purely obstetric antiphospholipid syndrome are at risk for thrombotic complications.

Arterial Blood-Flow Acceleration Time on Doppler Ultrasound Waveforms: What Are We Talking About?

In recent years, the assessment of systolic acceleration in lower-extremity peripheral artery disease (PAD) has been brought back into the spotlight, whatever measure is used: time (in s) or acceleration (in cm.s-2). Acceleration time (also called systolic rise time) and maximal acceleration are two different but very useful measurements of growing interest in PAD. A background of the historical development, physics rationale, semantics, and methods of measurement, as well as their strengths and weaknesses, are discussed herein. Acceleration time is a powerful tool for predicting significant arterial stenosis or for estimating the overall impact of PAD as it is highly correlated to the ankle or toe pressure indexes. It could even become a new diagnostic criterion for critical limb ischemia. Similarly, maximal systolic acceleration ratios are highly predictive of carotid or renal stenosis. However, the literature lacks reference standards or guidelines for the assessment of such variables, and their measurement techniques seem to differ between authors. We propose herein a semantic and measurement statement order to clarify and help standardize future research.

Acute effects of graduated and progressive compression stockings on leg vein cross-sectional area and viscoelasticity in patients with chronic venous disease.

OBJECTIVE: To determine the effects of graduated and progressive elastic compression stockings (ECS) on postural diameter changes and viscoelasticity of leg veins in healthy controls and in limbs with chronic venous disease (CVD). METHODS: In 57 patients whose legs presented with C1s, C3, or C5 CEAP classes of chronic venous disease and were treated primarily with compression, and 54 healthy controls matched for age and body mass index, we recorded interface pressures (IFP) at 9 reference leg levels. Cross-sectional areas of the small saphenous vein (SSV) and a deep calf vein (DCV) were measured with B-mode ultrasound with patients supine and standing, recording the force (PF) applied on the ultrasound probe to collapse each vein with progressive ECS, and with and without graduated 15 to 20 mm Hg and 20 to 36 mm Hg elastic stockings. We chose these veins because they were free of detectable lesion and could be investigated at the same level (mid-height of the calf), and their compression by the ultrasound probe was not hampered by bone structures. RESULTS: IFP decreased from ankle to knee with graduated 15 to 20 and 20 to 36 mm Hg, but increased with progressive ECS, and were 8.4 to 13.8 mm Hg lower for C1s than for control or C3 and C5 limbs. Without ECS, the SSV median [lower-upper quartile] cross-sectional area was 4.9 mm2 [3.6-7.1 mm2] and 7.1 mm2 [3.0-9.9 mm2] in C3 and C5 limbs versus 2.9 mm2 [1.8-5.2 mm2] and 3.8 mm2 [2.1-5.4 mm2] in controls (P < .01), respectively, while supine and standing. It remained greater in C3 and C5 than in C1s and control limbs wearing any ESC. Wearing compression, especially with progressive ECS, decreased the SSV and DCV cross-sectional area only with patients supine, thus decreasing postural changes, which remained highly diverse between individuals. The SSV cross-sectional area versus PF function traced a hysteresis loop of which the area, related to viscosity, was greater in C3 and C5 limbs than controls, even with graduated 15 to 20 or 20 to 36 mm Hg ECS. Progressive ECS decreased vein viscosity in the supine position, whereas 20 to 36 mm Hg and progressive ECS increased distensibility in the standing position. CONCLUSIONS: ECS decrease the cross-sectional area of SSV and DCV with patients supine, but not upright. C1s limbs show distinctive features, especially regarding IFP. Graduated 20 to 36 mm Hg and progressive stockings lower viscosity and increase distensibility of the SSV.

Skin Layer Thickness and Shear Wave Elastography Changes Induced by Intensive Decongestive Treatment of Lower Limb Lymphedema.

Background: A detailed quantitative evaluation would be beneficial for management of patients with limb lymphedema. Methods and Results: In 47 patients with lower limb lymphedema at International Society of Lymphology clinical stage 2A (18 limbs), 2B (41 limbs), and 3 (13 limbs), we measured the limb circumference and thickness of epidermis, dermis, and subcutis layers with B-mode ultrasonography and subcutis elastic modulus with ultrafast shear wave velocity (ultrasound elastography) at 5 anatomical levels (M1 to M5) before and after a 3- to 5-day intensive decongestive therapy (IDT) session. Limb circumference and thickness of the epidermis, dermis, and subcutis were greater in the 72 limbs with lymphedema than in the 22 unaffected limbs before and after IDT. The affected limb volume was 10,980 [8458-13,960] mL before and 9607 [7720-11,830] mL after IDT (p < 0.0001). The IDT-induced change in subcutis thickness was -9 [-25 to 13]% (NS), -11 [-26 to 3]% (p = 0.001), -18 [-40 to -1]% (p < 0.0001), -15 [-35 to 3]% (p = 0.0003), and -25 [-45 to -4]% (p < 0.0001) and significantly correlated with the change in elastic modulus, which was 13 [-21 to 90]% (p = 0.004), 33 [-27 to 115]% (p = 0.0002), 40[-13 to 169]% (p < 0.0001), 9 [-36 to 157]% (p = 0.024), and -13 [-40 to 97]% (NS), respectively, at the M1, M2, M3, M4, and M5 levels. Intraobserver reproducibility was satisfactory for skin thickness and fairly good for elastography, but interobserver reproducibility was poor or unacceptable. Conclusions: IDT reduced the circumference and subcutis thickness of lower limbs with lymphedema and increased their elastic modulus, implying greater tissue stiffness probably due to fluid evacuation. Although subcutis thickness measurement proved to be reliable, technological and methodological improvements are required before ultrasonographic elastography can be used in clinical practice.

Noninvasive measurement of venous wall deformation induced by changes in transmural pressure shows altered viscoelasticity in patients with chronic venous disease.

OBJECTIVE: The noninvasive measurement of venous wall deformation induced by changes in transmural pressure could allow for the assessment of viscoelasticity and differentiating normal from diseased veins. METHODS: In 57 patients with limbs in the C1s (telangiectasia or reticular veins and symptoms), C3 (edema), or C5 (healed venous ulcer) CEAP (clinical, etiologic, anatomic, pathophysiologic) category of chronic venous disease and 54 matched healthy controls, we measured the changes in the cross-sectional area of the small saphenous vein and a deep calf vein in the supine and standing positions and under compression with an ultrasound probe using ultrasonography. RESULTS: The small saphenous vein, but not the deep calf vein, cross-sectional area was smaller in the limbs of the controls than in the limbs with C3 or C5 disease but was not different from that in C1s limbs. When changing from the supine to the standing position, a greater force was required to collapse the leg veins. Their cross-sectional area increased in most subjects but decreased in 31.5% of them as for the small saphenous veins and 40.5% for the deep calf vein. The small saphenous vein area vs compression force function followed a hysteresis loop, demonstrating viscoelastic features. Its area, which represents the viscosity component, was greater (P < .001) in the pooled C3 and C5 limbs (median, 2.40 N⋅mm2; lower quartile [Q1] to upper quartile [Q3], 1.65-3.88 N⋅mm2) than in the controls (median, 1.24 N⋅mm2; Q1-Q3, 0.64-2.14 N⋅mm2) and C1s limbs (median, 1.15 N⋅mm2; Q1-Q3, 0.71-2.97 N⋅mm2). The area increased (P < .0001) in the standing position in all groups. CONCLUSIONS: Postural changes in the cross-sectional area of the leg veins were highly diverse among patients with chronic venous disease and among healthy subjects and appear unsuitable for pathophysiologic characterization. In contrast, small saphenous vein viscoelasticity increased consistently in the standing position and the viscosity was greater in limbs with C3 and C5 CEAP disease than in controls.

Subclinical cardiac abnormalities in human immunodeficiency virus-infected men receiving antiretroviral therapy.

Although cardiotoxic effects of highly active antiretroviral therapy (HAART) are a growing concern, there is a lack of prospective studies of subclinical involvement of the heart in human immunodeficiency virus (HIV)-infected patients. This study evaluated noninvasively cardiac morphologic characteristics and function in HIV-positive (HIV(+)) men receiving HAART for > or =2 years with no clinical evidence of cardiovascular disease. Echocardiography at rest, including tissue Doppler imaging and exercise testing, were performed in 30 HIV(+) men (age 42.1 +/- 4.7 years, duration of HIV infection 10.4 +/- 4.7 years, duration of HAART 5.3 +/- 2.1 years) and 26 age-matched healthy controls. At rest, HIV(+) patients had similar left ventricular (LV) mass indexed to height(2.7) (40.6 +/- 9.5 vs 37.5 +/- 9.3 g/m; p >0.05), but a higher prevalence of LV diastolic dysfunction (abnormal relaxation or pseudonormal filling pattern in 64% of patients vs 12% of controls; p <0.001). LV systolic function indexes were significantly lower (ejection fraction 60.4 +/- 8.7% vs 66.9 +/- 6.9%; p <0.01, and tissue Doppler imaging peak systolic velocity 11.4 +/- 1.6 vs 13.5 +/- 2.2 cm/s; p <0.001). Pulmonary artery pressure was higher in patients compared with controls (32.1 +/- 5.4 vs 26.1 +/- 6.5 mm Hg; p <0.001). Exercise testing showed decreased exercise tolerance in HIV(+) patients, with no case of myocardial ischemia. In conclusion, subclinical cardiac abnormalities are frequently observed in HIV(+) patients on HAART. The usefulness of systematic noninvasive screening in this population should be considered. GECEM study no. 30: National Agency for AIDS Research (ANRS).

Acute administration of l-arginine restores nitric oxide-mediated relaxation in isolated pulmonary arteries from pulmonary hypertensive exercise trained rats.

Hypoxia-induced pulmonary hypertension is associated with an impairment of nitric oxide-mediated vasorelaxation in the pulmonary circulation that is not prevented by exercise training. The present study was designed to test the hypothesis that a decrease in l-arginine bioavailability could be involved in this blunted response to exercise training. Male Wistar rats were randomly assigned to 4 groups: normotensive sedentary, normotensive trained, pulmonary hypertensive sedentary, pulmonary hypertensive trained. Pulmonary hypertension was induced by chronic exposure to hypobaric hypoxia (PIO(2) approximately 90 mmHg). Endothelium-dependent vasorelaxation to acetylcholine (10(-8)-10(-4) M) with or without l-arginine (10(-3) M) and/or nitro-l-arginine methyl ester (5.10(-6) M) was assessed on isolated pulmonary arterial rings. Maximal relaxation to acetylcholine was impaired in both pulmonary hypertensive groups. Acute l-arginine supplementation improved acetylcholine-induced vasorelaxation in the pulmonary hypertensive trained rats (P<0.01), to the level obtained in the normotensive sedentary ones, but not in the pulmonary hypertensive sedentary rats. This improvement was abolished when nitro-l-arginine methyl ester was added to the organ bath and was accounted for by an increase in eNOS protein content. These results confirm that the potential beneficial effect of exercise on nitric oxide-mediated pulmonary artery vasorelaxation is partly blunted by deleterious effects of hypoxia on l-arginine bioavailability. Further studies are needed to evaluate the benefit of the combination of exercise training and l-arginine supplementation for the treatment of pulmonary hypertension.

Systolic peak foot-to-apex time interval, a novel oscillometric technique for systolic blood pressure measurement.

BACKGROUND: Noninvasive blood pressure (BP) measurement is essential for the study of human physiology but automatic oscillometric devices only estimate SBP and DBP using various, undisclosed algorithms, precluding standardization and interchangeability. We propose a novel approach by tracking, during pneumatic cuff deflation, the time interval from the foot to the apex of the systolic peak of the oscillometric signal, which reaches a maximum concomitant with the first Korotkoff sound. METHOD: In 145 study participants and patients (group 1), we measured the systolic brachial artery blood pressure by Korotkoff sound recording, conventional oscillometry, and our fully automated systolic peak foot-to-apex time interval (SFATI) technique. In 35 other patients (group 2), we compared SFATI with intra-arterial measurement. RESULTS: In group 1, the concordance correlation coefficient was 0.989 and 0.984 between SFATI and Korotkoff sounds, 0.884 and 0.917 between oscillometry and Korotkoff sounds, and 0.882 and 0.919 between SFATI and oscillometry, respectively, on the left and right arm. In group 2, it was 0.72 between SFATI and intra-arterial measurement, 0.67 between oscillometry and intra-arterial measurement, and 0.92 between SFATI and Korotkoff sounds. In 40 study participants, the reproducibility study yielded a concordance coefficient of 0.95 for SFATI and 0.94 for Korotkoff sounds. CONCLUSION: SFATI BP measurement shows an excellent concordance with the auscultatory technique, offering a major improvement over current oscillometric techniques and allowing standardization.

An ultrasound look at Korotkoff sounds: the role of pulse wave velocity and flow turbulence.

AIMS: The aim of this study was to analyze the temporal relationships between pressure, flow, and Korotkoff sounds, providing clues for their comprehensive interpretation. MATERIALS AND METHODS: When measuring blood pressure in a group of 23 volunteers, we used duplex Doppler ultrasonography to assess, under the arm-cuff, the brachial artery flow, diameter changes, and local pulse wave velocity (PWV), while recording Korotkoff sounds 10 cm downstream together with cuff pressure and ECG. RESULTS: The systolic (SBP) and diastolic (DBP) blood pressures were 118.8±17.7 and 65.4±10.4 mmHg, respectively (n=23). The brachial artery lumen started opening when cuff pressure decreased below the SBP and opened for an increasing length of time until cuff pressure reached the DBP, and then remained open but pulsatile. A high-energy low-frequency Doppler signal, starting a few milliseconds before flow, appeared and disappeared together with Korotkoff sounds at the SBP and DBP, respectively. Its median duration was 42.7 versus 41.1 ms for Korotkoff sounds (P=0.54; n=17). There was a 2.20±1.54 ms/mmHg decrement in the time delay between the ECG R-wave and the Korotkoff sounds during cuff deflation (n=18). The PWV was 10±4.48 m/s at null cuff pressure and showed a 0.62% decrement per mmHg when cuff pressure increased (n=13). CONCLUSION: Korotkoff sounds are associated with a high-energy low-frequency Doppler signal of identical duration, typically resulting from wall vibrations, followed by flow turbulence. Local arterial PWV decreases when cuff pressure increases. Exploiting these changes may help improve SBP assessment, which remains a challenge for oscillometric techniques.

Femoral and axillary ultrasound blood flow during exercise: a methodological study.

PURPOSE: To use Doppler ultrasound 1) to assess the relationship between exercise intensity and changes in femoral and axillary artery diameter, 2) to determine whether volume blood flow (BF) measured during early recovery accurately reflects exercise BF, and 3) to assess the influence of artery caliber and/or site as well as exercise intensity on BF measurement reproducibility. METHODS: Thirteen healthy subjects (mean age 25.9+/-7.7 yr) performed progressive and maximal leg-extension (LE) and elbow-flexion (EF) exercises in the supine position. The duration of each stage was 150 s, followed by a 30-s recovery period. Arterial diameter and blood flow velocity were recorded simultaneously and continuously during the last 30 s of exercise as well as 30 s into recovery. RESULTS: Arterial dilation was 3.5 and 6.5% at maximal effort in femoral and axillary arteries, respectively. A significant increase was observed for both arteries from workload 2 to peak exercise when arterial cross-sectional area was calculated. Blood flow velocity during the recovery period was significantly different from end-exercise values, depending on time and workload. The coefficients of variation of BF measurement during exercise were 7.1-12.1% and 6.4-9.5% in LE and EF, respectively. CONCLUSION: This study showed that BF measurement with Doppler ultrasound during exercise is reproducible but requires measurement of arterial diameter at each workload. Measurements performed immediately after exercise cannot be used as a surrogate for blood flow velocity during exercise.

Prevalence and occurrence of stress urinary incontinence in elite women athletes.

OBJECTIVE: 1) To assess the prevalence of stress urinary incontinence (SUI) and urge urinary incontinence (UTI) in elite women athletes versus the general female population, and 2) to analyze the conditions of occurrence of urine loss in search of etiological clues in elite athletes. DECISION: An anonymous self-questionnaire was collected transversally from women aged 18 to 35 years. The exposed group was composed of elite female athletes; the non-exposed group was made up of women in the same age range accepting to answer the questionnaire. RESULTS: A total of 157 answers from elite athletes and 426 from control subjects were available for analysis. Urinary incontinence prevalence was 28% for athletes and 9.8% for control subjects (p = .001). There was no significant difference in the relative prevalence of SUI between the athletes and control subjects. Athletes reported urine loss more frequently during the second part of the training session (p < 0.0003), and the second part of competition (p < 0.05). Urinary incontinence prevalence was 9.87% in physically-active control subjects versus 9.84% in sedentary control subjects (NS). Even a small quantity of urine loss was felt to be embarrassing. Most incontinent women did not dare to speak of their condition to anybody. CONCLUSIONS: There is a very high prevalence of urinary incontinence in women athletes. Detailed studies of the patho-physiology of this problem are necessary to formulate preventive recommendations.

The association between hereditary thrombophilias and pregnancy loss.

The correlation between hereditary thrombophilia and fetal loss is supported by several observations. In murine models, the protein C system has been shown to be essential for the maintenance of pregnancy, as it indirectly acts as a growth factor for trophoblast cells and protects them from apoptosis. In humans, it has been shown that the placenta replaces the yolk sac as an essential source of blood supply to the embryo during the 8th and 9th weeks of gestation. Furthermore, meta-analysis of epidemiological data demonstrates a correlation between thrombophilic polymorphisms such as factor V Leiden and prothrombin 20210G-->A and isolated or recurrent fetal losses. Finally, therapeutic non-controlled trials indicate the benefits and safety of low-molecular weight heparins as secondary prophylaxis. However, it is still necessary to further clarify the association between thrombophilia and fetal loss, especially during a first pregnancy, with regard to the type of pregnancy loss and with respect to other related factors.

Training does not affect the alteration in pulmonary artery vasoreactivity in pulmonary hypertensive rats.

This study examined the effects of training on intrinsic vasorelaxation and vasoconstriction properties of pulmonary hypertensive rat arteries. Fifty seven male Wistar rats were randomly assigned to 4 groups: normotensive sedentary (n = 14), normotensive trained (n = 15), pulmonary hypertensive sedentary (n = 15) and pulmonary hypertensive trained (n = 13). Pulmonary hypertension was obtained using a chronic hypoxia exposure model. Endothelium-dependent vasorelaxation to acetylcholine (10(-8)-10(-4) M), endothelium-independent vasorelaxation to sodium nitro-prusside (10(-8)-10(-4) M), and vasoconstriction to epinephrine (10(-9)-10(-4) M) and endothelin-1 (10(-12)-10(-7) M) were assessed on isolated rings of large pulmonary arteries. Alterations in endothelium-dependent and -independent vasorelaxation properties as well as enhanced vasoconstrictor responses were obtained in pulmonary hypertensive rats. Chronic exercise did not affect those pulmonary vasoreactivity alterations. A predominant effect of chronic hypoxia over training seems to be partially responsible for this phenomenon, probably through impairment in nitric oxide bioavailability and vascular smooth muscle sensitivity.

Altitude negates the benefits of aerobic training on the vascular adaptations in rats.

INTRODUCTION: This study questioned the effect of living and training at moderate altitude on aortic vasoreactivity. Considering that chronic hypoxia exposure and endurance training are able to generate opposite effects on the systemic vascular reactivity, it was hypothesized that endurance training benefits on the vascular function could be limited by chronic hypoxia. METHODS: Sea-level native rats were randomly assigned to N (living in normoxia), NT (living and training 5 d.wk for 5 wk in normoxia), CH (living in hypoxia, 2800 m), and CHT (living and training 5 d.wk for 5 wk in hypoxia, 2800 m) groups. Concentration response curves to epinephrine, norepinephrine, endothelin-1, acetylcholine, and sodium nitro-prusside were assessed on aortic isolated rings. Left ventricular resting and maximal (during Tyrode's infusion) stroke volumes were evaluated by Doppler-echocardiography and used as indexes of chronic aortic volume overload. RESULTS: The main finding was that favorable aortic vasoreactivity adaptations consecutive to sea-level training were not observed when training was conducted at altitude. An improvement in the endothelium-dependent vasorelaxation (maximal relaxation, R(max), N = 60.4 +/- 10.0 vs NT = 91.7 +/- 3.2%; P < 0.05) and a reduced sensitivity to ET-1 were observed in NT rats. Such an enhancement in endothelium-dependent vasorelaxation was not found in CHT rats (R(max): 48.4 +/- 7.8%). Moreover, a higher sensitivity to ET-1 was reported in this group. Altitude-induced limitation in aortic blood flow and shear stress could play a major role in the explanation of these specific altitude-training adaptations. CONCLUSION: If extrapolated to the peripheral vascular bed, our results have practical significance for aerobic performance as aortic vasoreactivity adaptations after altitude training could contribute to limit blood delivery to exercising muscles.

Wall mechanics of the stented extracranial carotid artery.

BACKGROUND AND PURPOSE: Abrupt compliance changes and concomitant nonlaminar flow patterns may contribute to endothelial dysfunction and subsequent neointimal thickening. The aim of this study was to test the feasibility of wall mechanics measurement using B-mode ultrasound image analysis by dedicated software in the stented human carotid artery. METHODS: Carotid Wallstents (Schneider) were placed in the extracranial carotid arteries of 15 patients. B-mode ultrasound examination was performed with a 7.5-MHz probe on the carotid artery upstream; at the proximal, mid, and distal stent levels; downstream from the stent; and on the contralateral internal and common carotid arteries. Carotid diameter (d) and systolic diameter changes (Deltad) were measured with a dedicated image processing system (IO version 3.1, IODP), while pulse blood pressure (DeltaP) was measured. Diameter compliance (Cd) and distensibility coefficient (DC) were calculated as Cd=2Deltad/DeltaP and DC=2Deltad/DeltaP/d and compared between measurement sites. RESULTS: The evaluation could be completed in 8 of 15 patients. Compliance was significantly lower at the proximal, mid, and distal stent levels (27.77+/-1.11, 27.38+/-1.08, 27.38+/-1.09x10(-3) mm x kPa(-1)) than upstream (103.3+/-36.7x10(-3) mm x kPa(-1)), downstream (91.5+/-41.3x10(-3) mm x kPa(-1)), or on the contralateral internal (87.6+/-28x10(-3) mm x kPa(-1)) and common (149.3+/-47.6x10(-3) mm x kPa(-1)) carotid arteries. CONCLUSIONS: Stenting of the extracranial carotid artery induces a compliance mismatch between the native and the stented artery.

Hormone replacement therapy with estradiol valerate and cyproterone acetate: effects on endothelium-dependent vasodilatation and arterial wall compliance.

OBJECTIVE: to evaluate changes in vasomotor endothelium function and elastic properties of the brachial artery in postmenopausal women beginning hormone replacement therapy (HRT) with Climen(R), a 28-day sequential therapy combining estradiol valerate (E2V) 2 mg/day D1-D21 with cyproterone acetate (CPA) 1 mg/day D12-D22, followed by a 7-day treatment-free interval. METHODS: Thirty-one women with natural or surgical menopause were included in an open multicenter study. Before treatment, at the end of the estrogen-only phase of cycle 1, and after the combined phase in cycles 1 and 3, endothelium-dependent vasodilatation (EDVD%) in the brachial artery was measured by the post-ischemia increase of the inner diameter, and pulse wave velocity (PWV) was measured in the same artery by simultaneous continuous wave Doppler and photo-plethysmography. RESULTS: compared to pre-treatment values, the median increase in EDVD was 14.3% after cycle 1 (P=0.0001) and 27.9% after cycle 3 (P=0.0001). CPA did not alter the effect of E2V on EDVD in cycle 1. Median arterial systolic pressure was unchanged, but median diastolic pressure fell from 70 to 67.5 mmHg (P=0.04) after cycle 3. Median PWV was reduced by 0.76 m/s after cycle 3 (relative reduction -9.3%) (P=0.035). There was a significant correlation between PWV and EDVD changes from pre-treatment values at the end of the 3rd cycle. CONCLUSION: treatment of postmenopausal women with E2V/CPA led to an immediate and significant improvement in endothelium-dependent vasodilatation. The estrogen-related vasomotor effect was not suppressed by the progestogen CPA. The WV changes are consistent with slower improvement of arterial compliance in some women. The non-invasive measurement of EDVD and PWV is a convenient method for the evaluation of both mechanical and functional effects of combination HRT on the arterial wall.

Validation of a newly developed B-mode image-processing technique versus wall-tracking ultrasound for the study of wall mechanics in small-calibre arteries.

PURPOSE: To validate a newly developed image-processing technique for the assessment of arterial wall compliance and distensibility from non-invasive B-mode ultrasound compared with the invasive wall-tracking technique. MATERIALS AND METHODS: Arterial wall compliance and distensibility coefficient were measured invasively by wall-tracking with an ultrasonic transducer implanted on the vessel wall, and non-invasively by automatic processing of B-mode ultrasound images, with a dedicated workstation and software (IO 3.1, IODP, Paris). Measurements were performed in the normal aorta of five animals, and upstream, at the stent level, and downstream from the stent in eight other animals (immediately after stenting in six, and 3 months later in four), for a total of 35 paired measurements. RESULTS: There was no significant difference between the two techniques for compliance but there was a significant difference in diameter (P<0.005) and distensibility (P<0.05) as external ultrasound measured the inner diameter, while wall-tracking measured the outer diameter. Agreement between the two methods as assessed by the Bland-Altman approach was acceptable for aortic diameter, compliance and distensibility. CONCLUSION: Automatic processing of B-mode ultrasound images is a reliable non-invasive technique to assess the compliance of small-calibre arteries.

Towards a quantitative in vivo evaluation of venous blood echogenicity: image processing versus subjective assessment.

PURPOSE: Spontaneous blood echogenicity in vein ultrasound images may be a marker for an increased erythrocyte aggregability, but a reliable quantitative evaluation method is a prerequisite for its use in clinical studies. We compared a simple scoring system of blood echogenicity intensity and pattern, with automatic image analysis. MATERIAL AND METHODS: 157 femoral and popliteal vein digitized ultrasound sequences were reviewed by two independent observers who chose an image, delimited an area of interest (ROI), and graded blood echogenicity intensity and pattern, using a four class score. Each observer reviewed the images selected by the other, without and with ROI. The computer calculated first and second order parameters describing echo intensity and spatial organization. RESULTS: Inter-observer reproducibility of subjective assessment was poor (Kappa<0.5), whereas the automatically calculated ROI average gray level intensity relatively to the whole image (tau(1)) effectively separated all grades of intensity. No parameter effectively separated patterns. CONCLUSION: Tau(1) is a simple parameter for the in vivo evaluation of blood echogenicity intensity. It should be evaluated in standardized conditions for clinical hemorheology studies in correlation with in vitro erythrocyte aggregation measurements.

Endurance training minimizes age-related changes of left ventricular twist-untwist mechanics.

BACKGROUND: The aim of this study was to test the effect of endurance training on the age-related changes of left ventricular (LV) twist-untwist mechanics. Aging has been shown to induce a decline of diastolic function and more recently an impairment of twist-untwist mechanics, which constitutes an important factor for early diastolic suction and filling. On the other hand, endurance training has been shown to improve cardiac function. METHODS: Speckle-tracking echocardiography was performed in 106 endurance-trained male athletes and 75 controls (age range 18-70 years), divided into three groups according to age. RESULTS: From the younger to older age groups, progressive increases in LV apical rotation and twist angle and a decrease in LV untwisting rate during isovolumic relaxation time were observed. Athletes had lower systolic twist angles (P < .01) but higher untwist/twist ratios and LV untwisting rate during isovolumic relaxation time compared with controls, with the largest difference between senior groups (51 ± 24% vs 42 ± 22% in the young and 42 ± 29% vs 24 ± 25% in seniors, P < .001, respectively). The normal timing of untwisting rate occurring before radial displacement was preserved in athletes with increasing age, whereas it was blunted in controls. CONCLUSIONS: Endurance training does not prevent but minimizes changes in LV twist-untwist mechanics from young subjects to seniors. Athletes showed smaller increases of twist angle with age and smaller declines of LV untwisting rate during isovolumic relaxation time and untwist/twist ratio compared with controls. This training-improved preservation of LV twist-untwist mechanics is likely to play a key role for systolic-diastolic coupling and diastolic filling, particularly during exercise.