Pulse Wave Velocity Measurements Research Articles

Group delay method for MRI aortic pulse wave velocity measurements in clinical protocols with low temporal resolution: Validation in a heterogeneous cohort

BackgroundMRI assessment of aortic pulse wave velocity (PWV) helps predict the risk of vascular events, but the recommended phase contrast sampling rate is faster than what is utilized in most clinical sequences. There are many existing MRI databases obtained for assessment of cardiac output using lower temporal frequency sampling where information might be obtained about aortic stiffness (PWV). In this work, we sought to evaluate whether the Group Delay (GD) method can generate a reproducible measure of stiffness and describe expected age-related stiffening of the aortic arch using lower sampling rates in standard clinical sequences. MethodsPhase contrast (PC) MRI was obtained on the ascending and descending aortic arch in a heterogeneous adult cohort (n = 23; 9 women) spanning over a wide range of ages (ages 24–89, mean 49.4 ± 18.4). Data was collected with standard cardiac MRI protocols for cardiac output evaluation (repetition time = 7.8 ms, views-per-segment = 4, encoding velocity = 200 cm/s). Pulse wave transit times (TT) were computed using the GD method, two other validated automated approaches (cross correlation TT Algorithm by Gaddum and Segment by Medviso), and the manual tangent method. Pressure waveforms from tonometry and flow waveforms from PC MRI were used to assess wave reflections. ResultsGroup Delay and TT-Algorithm showed significant and high retest reproducibility (r = 0.86 for both) as well as high PWV correlation with age (r = 0.93, P-value < 0.00005 and r = 0.96, P-value < 0.00005 respectively) and with each other (r = 0.94, P-value < 0.00001, RMSE = 0.94 m/s). Arbitrary altering of the image acquisition trigger in the GD method introduced error of 10%–13%, but the TT-algorithm error range was 11%–25%. ConclusionGroup Delay enables reproducible assessment of transit time to derive PWV from low temporal resolution clinical cardiac MRI sequences that can also identify age-related stiffening.

The relationship between the severity of erectile dysfunction and aortic stiffness.

Aortic stiffness increases in patients with erectile dysfunction (ED) but it is not known whether aortic stiffness affects the degree of ED. In the present study, we aimed to determine whether there is any relationship between aortic stiffness and the severity of ED. Patients with ED were divided into 3 groups according to the International Index of Erectile Function (IIEF) scores. Mild ED was named as group 1, moderate ED as group 2 and severe ED as group 3. The values of fasting blood glucose (FBG), serum lipid values, total testosterone (T. tes), and free testosterone (F tes) were recorded. Aortic stiffness was determined by pulse wave velocity (PWV) and augmentation index (AIX) measurements. The mean or median values of the laboratory parameters among the groups were similar (p>.05). No statistical difference was found between the groups in terms of AIX value (p=.386). Mean PWV values were calculated as 7.26, 8.30 and 8.78 in group 1, group 2 and group 3 respectively. PWV values were significantly different between groups (p<.0001). PWV values were found to be increased with increasing severity of erectile dysfunction.

Ultrasound measument of local arterial stiffness through one-point echo-tracking technique

A recent guideline on hypertension of the European Society of Cardiology recommends assessment of hypertensive organ damage. One of these aspects is the measurement of pulse wave velocity as an index of arterial stiffness and underlying atherosclerosis. Pulse wave velocity measurement provides valuable predictive information added to standard risk factors such as blood pressure, lipids, and blood glucose in cardiovascular risk assessment. The recently introduced ultrasound echo-tracking technique is considered a modern aspect in measuring local arterial siffness in clinical practice. The carotid artery is of particular interest because of its easy accessibility and the data obtained from numerous studies on the predictive value of the carotid pulse wave velocity for cardiovascular events.

Arterial Stiffness in Hypertension and Function of Large Arteries.

Arterial stiffness-typically assessed from non-invasive measurement of pulse wave velocity along a straight portion of the vascular tree between the right common carotid and femoral arteries-is a reliable predictor of cardiovascular risk in patients with essential hypertension. We reviewed how carotid-femoral pulse wave velocity increases with age and is significantly higher in hypertension (than in age- and gender-matched individuals without hypertension), particularly when hypertension is associated with diabetes mellitus. From the elastic aorta to the muscular peripheral arteries of young healthy individuals, there is a gradual but significant increase in stiffness, with a specific gradient. This moderates the transmission of pulsatile pressure towards the periphery, thus protecting the microcirculatory network. The heterogeneity of stiffness between the elastic and muscular arteries causes the gradient to disappear or be inversed with aging, particularly in long-standing hypertension. In hypertension therefore, pulsatile pressure transmission to the microcirculation is augmented, increasing the potential risk of damage to the brain, the heart, and the kidney. Furthermore, elevated pulse pressure exacerbates end-stage renal disease, particularly in older hypertensive individuals. With increasing age, the elastin content of vessel walls declines throughout the arterial network, and arterial stiffening increases further due to the presence of rigid wall material such as collagen, but also fibronectin, proteoglycans, and vascular calcification. Certain genes, mainly related to angiotensin and/or aldosterone, affect this aging process and contribute to the extent of arterial stiffness, which can independently affect both forward and reflected pressure waves.

Evaluation of increased arterial stiffness in pediatric patients with cystic fibrosis by augmentation index and pulse wave velocity analysis.

With the increase in life expectancy, cardiovascular complications of cystic fibrosis (CF) have come to the forefront. Increased arterial stiffness is a marker of increased cardiovascular risk. The aim of this study was to compare both pulse wave velocity (PWV) and augmentation index (Aix) measurements in children with CF and to compare them with healthy controls. We hypothesized that children with CF had increased arterial stiffness, although traditional risk factors for CVD were not observed. Forty-four patients and age and sex-matched 30 healthy controls were included in the study. Hemodynamic measurements were compared in both groups, together with traditional risk factors. Peripheral blood pressure parameters of CF and control groups were similar (P > .05). Bodyweight and BMI were significantly lower in the CF group (P < .001). Serum cholesterol, HDL, and LDL levels were significantly lower in the CF group, whereas fasting blood glucose and triglyceride levels were significantly higher than the control group (P < .05). Mean ± SD Aix was significantly higher in the CF group (33.22 ± 13.87%) compared with the control group (24.93 ± 10.58%), respectively (P < .05), while PWV was similar. No significant correlation between PWV and Aix and fasting blood glucose and lipid profile in both groups (P > .05). Children with CF have been shown to have increased arterial stiffness compared to healthy children. Although there are not many traditional risk factors, increased arterial stiffness have been demonstrated in children with CF. The effects of this process starting from childhood on the development of CVD in adulthood are not known. Therefore, further studies are needed.

Matrix metalloproteinase −2, −9 and arterial stiffness in children and adolescents: The role of chronic kidney disease, diabetes, and hypertension

Background and aimsMatrix metalloproteinases (MMPs) may contribute to the pathogenesis of arterial stiffness inducing extracellular matrix remodeling. We aimed to compare MMP-2 and -9 levels in children with chronic kidney disease (CKD), type 1 diabetes (without chronic kidney disease) and healthy control and to investigate associations of MMPs levels with cardiovascular risk factors and markers of arterial stiffness. MethodsThe study population included 33 CKD, 18 type 1 diabetes patients, and 24 healthy controls. MMP-2, MMP-9, office blood pressure, pulse wave analysis, and carotid-femoral pulse wave velocity (cfPWV) measurements were performed. ResultsMMP-2 levels were higher in the CKD compared to the diabetes and control groups (p < 0.05). MMP-9 levels did not differ among groups. In hypertensive individuals logMMP-2 independently associated with PWV z score (β = 0.744, 95%CI 0.105 to 2.921, p < 0.05) after adjustment for age, sex, GRF, and phosphate levels. Creatinine levels correlated positively with MMP-2 in the CKD (r = 0.39, p < 0.05) and negatively in the diabetes group (r = −0.72, p < 0.05). Cholesterol levels correlated with MMP-2 in the diabetes group (r = 0.70, p < 0.05). Phosphate levels correlated with MMP-2 level in the control group (r = 0.67, p < 0.05). In multivariate regression model adjusted for age and sex, including phosphate and GRF as covariates, only phosphate predicted logMMP-2 levels (β = 0.333, 95%CI 0.060 to 0.671, p < 0.05). ConclusionsMMP-2 associated with arterial stiffness in the presence of hypertension, while the role of MMP-9 is less clear in children with CKD or type 1 diabetes. Whether up-regulation of MMPs could predict poor outcomes in young high-risk patient groups need to be confirmed by future studies.

The Tyrolean early vascular ageing-study (EVA-Tyrol): study protocol for a non-randomized controlled trial

BackgroundAccording to the World Health Organization, cardiovascular diseases (CVDs) are the leading non-communicable cause of death. Awareness of the individual risk profile is crucial to implement a healthy lifestyle and prevent CVDs. Multiple studies demonstrated that atherosclerosis, the main cause of CVDs, begins early in life. Therefore, it may be necessary to start prevention programs already in childhood.MethodsThe EVA-Tyrol study is a population-based non-randomized controlled trial that will prospectively enroll 2000 participants from high schools and training companies in North- and East-Tyrol (Austria) and South-Tyrol (Italy). Participants will be assigned to either an intervention (n = 1500) or a control (n = 500) group. Intervention group participants will be enrolled at the 10th school grade (mean age 15–16 years), undergo two examinations within a two-year interval, with follow-up at the 12th grade (mean ages 17–18 years). Control group participants will be enrolled at the 12th grade (mean age 17–18 years). Medical examination will include anthropometric measurements, comprehensive lifestyle and dietary questionnaires, a fasting blood sample, high-resolution ultrasound of the carotid arteries, and measurement of carotid-femoral pulse wave velocity. Active intervention will consist of (1) enhancing knowledge about CVDs, (2) individual medical counseling based on the results of the baseline examination, (3) an online health promotion tool and (4) involvement of participants in planning and implementation of health promotion projects. Effectiveness of the intervention will be assessed by comparing the proportion subjects with ideal health metrics as defined by the American Heart Association between study groups.DiscussionThis study aims to improve cardiovascular health in Tyrolean adolescents by demonstrating the efficacy of a multi-layer health promotion program and may yield novel insights into the prevalence of vascular risk conditions and mechanisms of early vascular pathologies in adolescents.Trial registrationEVA-Tyrol has been retrospectively registered at clinicaltrials.gov under NCT03929692 since April 29, 2019.

Relationship between BMI and aortic stiffness: influence of anthropometric indices in hypertensive men and women.

Increased aortic stiffness could be one of the mechanisms by which obesity increases cardiovascular risk independently of traditional risk factors. Studies have suggested that anthropometric indices may be predictors of cardiovascular risk but few studies have investigated their relations with aortic stiffness in high cardiovascular risk population. We investigated the strength of correlation between different anthropometric indices with aortic stiffness in hypertensive and diabetic patients. A cross-sectional study was performed in 474 hypertensive patients. Anthropometric indices were calculated: BMI, waist circumference, waist-hip ratio, and waist-height ratio (WHtR). Aortic stiffness was assessed by measurement of carotid-femoral pulse wave velocity (PWV). Correlations between indices and PWV were investigated by linear regression analyses and hierarchical analyses after adjusting for cardiovascular risk factors. Regional anthropometric indices were more strongly correlated with PWV than BMI in both sexes. In linear regression analyses, WHtR presented the highest correlation with PWV than other indices in our study population. In adjusted hierarchical regression used, WHtR had the highest additive value on top of BMI while there no additive value of BMI on top of WHtR. These differences remained after adjustment on cardiovascular events. In men WHtR was more closely correlated with PWV than others. In women, waist-hip ratio and WHtR were equally correlated with PWV compared with BMI. Regional anthropometric indices are more closely correlated with PWV than BMI in hypertensive patients. WHtR presents the highest correlation with PWV beyond BMI. The study was registered in the French National Agency for Medicines and Health Products Safety (No. 2013-A00227-38) and was approved by the Advisory Committee for Protection of Persons in Biomedical Research.

Abstract WP265: Association Between Brachial-Ankle Pulse Wave Velocity and Aortic Atheroma in Acute Ischemic Stroke

Background and Purpose: Aortic plaques are associated with both larger artery and small artery atherosclerosis. However, association between aortic plaque and aortic stiffness in ischemic stroke is unknown. Brachial-ankle pulse wave velocity (baPWV) is a noninvasive technique to measure aortic stiffness. In the present study, we hypothesized that presence of aortic plaques is associated with increased baPWV. Methods: We reviewed 1099 patients diagnosed with acute ischemic stroke, who had both transesophageal echocardiography (TEE) and brachial-ankle pulse wave velocity (baPWV) measurements. Aortic plaques were classified as complex aortic plaques (CAP) or simple aortic plaques (SAP). CAP were defined as plaques protruding into the lumen ≥4 mm and of mobile lesions located in the proximal aorta. SAP represented plaques &lt;4 mm in the proximal aorta and plaques located in the descending aorta of any sizes. Patients were classified into 4 groups; patients who have CAP only, those who have SAP only, those who have both CAP and SAP, and those without aortic plaques. Results: Among the 1099 patients, aortic atheroma was found in 689 (62.7%) patients. Twenty one (1.9%) patients had only CAP, 142 (12.9%) patients had both SAP and CAP, while 526 (47.9%) patients had SAP without CAP. Mean value of baPWV was 1982±580 cm/sec. baPWV was significantly increased in patients with any aortic atheromas than those without atheromas (2095±577 cm/sec vs. 1793±535 cm/sec, p &lt;0.001). Analysis of variance showed that baPWV was significantly increased in patients with SAP only (p&lt;0.001) and SAP and CAP (p&lt;0.001) compared to those without any aortic atheroma, whereas CAP only patients were not associated with baPWV (p = 0.131). Conclusion: We found that baPWV was associated with SAP but not CAP in acute ischemic stroke patients. These feature suggests that SAP represent generalized atherosclerosis and aortic stiffness, whereas CAP represent the sole mechanism of stroke.

Relationship between arterial stiffness and unattended or attended blood pressure values.

Measurement of 'unattended' blood pressure (BP) may reduce or eliminate the 'white-coat effect'. Despite the possible advantages of this approach for BP measurement, only few studies analysed the relationship between unattended BP and cardiovascular events or with hypertension-mediated organ damage (HMOD). The aim of our study was to evaluate the relationship between 'attended' or 'unattended' BP values and carotid-femoral pulse wave velocity (PWV) in 285 individuals undergoing a visit and assessment of arterial stiffness at an ESH Excellence Centre. Unattended BP (measured with the patient alone in the room, with an oscillometric device programmed to perform three BP measurements, at 1-min intervals, after 5 min) and attended BP were measured with the same device, on the same day of the measurement of PWV, in a random order. Mean age was 63 ± 13 years, mean BMI 26 ± 4, 47% were women, 76% had hypertension (55% treated). Systolic unattended BP was lower than attended SBP (124.4 ± 14.3 vs. 130.9 ± 16.1 mmHg). PWV was similarly correlated with attended and unattended SBP values (r = 0.428 and r = 0.404, P < 0.0001, respectively). No difference for the prediction of increased arterial stiffness was observed at receiver operator curves (ROCs) analysis [attended SBP area under the curve (AUC) 0.665, 95% confidence interval (95% CI) 0.607-0.720 vs. unattended SBP: AUC 0.651, 95% CI 0.593-0.706, P for the comparison = ns]. Attended and unattended BP values are similarly correlated with PWV, the gold standard measure of arterial stiffness. These findings may provide further information on the clinical value of unattended BP.

Association of pulse wave velocity and intima-media thickness with cardiovascular risk factors in young adults.

Pulse wave velocity (PWV), a measure of arterial stiffness, and intima‐media thickening (IMT), a measure of early atherosclerosis, are intermediate markers of cardiovascular disease which are predictive of cardiovascular events. Traditionally, both were thought to result from accumulative exposure to traditional cardiovascular risk factors. However, their association with risk factors in young adults in low‐income settings is unknown. We sought to investigate the association between PWV and IMT with traditional cardiovascular risk factors in the Andhra Pradesh Children and Parents Study cohort from Southern India. Male and female adults (N = 1440) aged between 20 and 24 years underwent measures of PWV and IMT. Exposure variables included smoking, body mass index (BMI), mean arterial pressure (MAP), glucose, homeostatic model assessment of insulin resistance (HOMA‐IR), total cholesterol, high‐density lipoprotein cholesterol (HDL‐cholesterol), and triglycerides. Association between outcome and exposure variables was assessed using linear regression analysis. Average values for PWV and IMT were 5.9 ± 0.6 m/s and 0.5 ± 0.1 mm. In univariable analysis, PWV associated with MAP, BMI, smoking, total cholesterol, glucose, and HOMA‐IR and IMT associated with MAP, BMI, tobacco use, and HDL‐cholesterol. In multivariable analysis, PWV remained strongly positively associated with MAP increasing by 0.5 m/s (P < .001) for a 10 mm Hg increase in MAP (R 2 = .37). In contrast, IMT negatively associated with HDL‐cholesterol (β = −.10; P = .012, R 2 = .02). There was weak evidence that PWV and IMT positively associated with BMI. In young adults from Southern India, PWV positively associated with blood pressure and IMT negatively associated with HDL‐cholesterol. This suggests separate etiologies for atherosclerosis and arterial stiffening in young adults.

A Photoplethysmographic Monitor for Local Pulse Wave Velocity Measurement

A Photoplethysmographic Monitor for Local Pulse Wave Velocity Measurement

Personalising cardiovascular network models in pregnancy: A two-tiered parameter estimation approach.

Uterine artery Doppler waveforms are often studied to determine whether a patient is at risk of developing pathologies such as pre‐eclampsia. Many uterine waveform indices have been developed, which attempt to relate characteristics of the waveform with the physiological adaptation of the maternal cardiovascular system, and are often suggested to be an indicator of increased placenta resistance and arterial stiffness.Doppler waveforms of four patients, two of whom developed pre‐eclampsia, are compared with a comprehensive closed‐loop model of pregnancy. The closed‐loop model has been previously validated but has been extended to include an improved parameter estimation technique that utilises systolic and diastolic blood pressure, cardiac output, heart rate, and pulse wave velocity measurements to adapt model resistances, compliances, blood volume, and the mean vessel areas in the main systemic arteries. The shape of the model‐predicted uterine artery velocity waveforms showed good agreement with the characteristics observed in the patient Doppler waveforms. The personalised models obtained now allow a prediction of the uterine pressure waveforms in addition to the uterine velocity. This allows for a more detailed mechanistic analysis of the waveforms, eg, wave intensity analysis, to study existing clinical indices. The findings indicate that to accurately estimate arterial stiffness, both pulse pressure and pulse wave velocities are required. In addition, the results predict that patients who developed pre‐eclampsia later in pregnancy have larger vessel areas in the main systemic arteries compared with the two patients who had normal pregnancy outcomes.

Measurement of local pulse wave velocity for carotid artery by using an ultrasound-based method

Currently, pulse wave velocity (PWV) is an important physical index for characterizing the mechanical properties of arteries. Carotid-femoral PWV (cfPWV) is a clinically-approved parameter for evaluating the cardiovascular risk and therapeutic efficacy. However, cfPWV only provides global information about vessel properties. Many recent studies have indicated that local PWV measurements provide precise evaluation of artery conditions. Here, an ultrasound (US) method based on a novel vessel displacement waveform correction, is proposed for improving the accuracy of local carotid PWV measurement. A programmable US device and a commercial array transducer were used, which allow a user to excite transducer and receive US signals arbitrarily with different beam settings. The local PWV measurement accuracy was verified using a phantom. The number of US beams used for PWV measurements was also considered, which indicates that eight elements is the acceptable setting. Subsequently, local carotid PWV and cfPWV were measured in 35 healthy human subjects (age: 21.9 ± 2.4 years) by using the US method and SphygmoCor device, respectively. The cfPWV and local carotid PWV were 6.65 ± 0.74 and 4.63 ± 0.57 m/s, respectively. A good linear correlation was observed between the two aforementioned methods (r = 0.8) for the subjects. All the results indicated that when few US beams were used, the proposed method exhibited a reliable measurement of local PWV.

Pulse Wave Analysis and Pulse Wave Velocity for Fistula Assessment

Background/Aims: Pulse wave analysis (PWA) and pulse wave velocity (PWV) provide information about arterial stiffness and elasticity, which is mainly used for cardiovascular risk stratification. In the presented prospective observational pilot study, we examined the hypothesis that radiocephalic fistula (RCF)-related changes of haemodynamics and blood vessel morphology including high as well as low flow can be seen in specific changes of pulse wave (PW) morphology. Methods: Fifty-six patients with RCF underwent local ambilateral peripheral PWA and PWV measurement with the SphygmoCor® device. Given that the output parameters of the SphygmoCor® are not relevant for the study objectives, we defined new suitable parameters for PWA in direct proximity to fistulas and established an appropriate analysing algorithm. Duplex sonography served as reference method. Results: Marked changes of peripheral PW morphology when considering interarm differences of slope and areas between the fistula and non-fistula arms were observed in the Arteria radialis, A. brachialis and arterialized Vena cephalica. The sum of the slope differences was found to correlate with an increased flow, while in patients with fistula failure no changes in PW morphology were seen. Moreover, PWV was significantly reduced in the fistula arm. Conclusion: Beside duplex sonography, ambilateral peripheral PWA and PWV measurements are potential new clinical applications to characterize and monitor RCF function, especially in terms of high and low flow.

Oscillometric Measurement of Pulse Wave Velocity in Hypertensive Crisis

Oscillometric Measurement of Pulse Wave Velocity in Hypertensive Crisis

ОЦЕНКА СЕРДЕЧНО-СОСУДИСТОГО РИСКА У МУЖЧИН В ВОЗРАСТЕ 18-29 ЛЕТ

We aimed to develop a model for summary cardiovascular risk (CVR) assessment in men aged 18-29. A total of 165 men were examined using cycling ergometry, analysis of heart rate variability (HRV) and measurement of pulse wave velocity in muscle-type arteries (PWVm). A high summary CVR was detected in 38 patients (23%). The proposed model includes such indicators as heart rate during office measurement, waist circumference, left ventricular myocardial mass index, PWVm, type of hemodynamic response to physical exercise, diastolic blood pressure morning surge obtained from ambulatory blood pressure measurement as well as index of centralization obtained from HRV analysis. The model has high sensitivity (85.7%) and specificity (89.1%).

The Influence of Aortic Pulse Wave Velocity on Short-Term Functional Capacity in Patients with Mild Paravalvular Regurgitation Following Transcatheter Aortic Valve Implantation.

IntroductionRecently, the clinical significance of mild paravalvular aortic regurgitation (PAR) has been evaluated and suggested that it can be predictor of clinical outcomes. In our study, we aimed to investigate the interaction of aortic pulse wave velocity (PWV) and mild PAR and their effects on the functional status of patients after transcatheter aortic valve implantation (TAVI).MethodsA total of 109 consecutive patients with symptomatic severe aortic stenosis were enrolled prospectively. After TAVI procedure, they were divided in to three groups according to PAR and PWV measurements. Patients without PAR were defined as the NonePAR group (n=60), patients with mild PAR and normal PWV were defined as the MildPAR-nPWV group (n=23), and patients with mild PAR and high PWV were defined as the MildPAR-hPWV group (n=26).ResultsCompared with other groups, the MildPAR-hPWV group was older (P<0.001), hypertensive (P=0.015), and had a higher pulse pressure (P=0.018). In addition to PWV, this group had lower aortic regurgitation index (ARI) (P=0.010) and higher rate of New York Heart Association (NYHA) class II (at least) patients (P<0.001) in 30-day follow-up period. On multivariate regression analysis, the MildPARhPWV group (odds ratio=1.364, 95% confidence interval 1.221-1.843; P=0.011) as well as N-terminal-pro-brain natriuretic peptide levels and ARI were independently related with 30-day functional NYHA classification. However, NonePAR or MildPAR-nPWV group was not an independent predictor of early functional status.ConclusionIt was concluded that high PWV may adversely affect early functional status in patients with mild PAR in contrast to normal values following TAVI.

Effect of supra-physiological estrogen level on arterial stiffness and hemodynamic parameters

The present study evaluates the arterial stiffness and hemodynamic parameters in patients with a supraphysiological estrogen level due to in vitro fertilization (IVF) with controlled ovarian hyperstimulation (COH).A total of 82 female patients aged 24-45 years were included. Their arterial stiffness parameters were analyzed before and after the appropriate COH protocol involving arteriography using Mobil-O-Graph NG (IEM GmbH, Stolberg, Germany) 24-hour ambulatory blood pressure monitor.Systolic, diastolic, mean, central systolic, and diastolic blood pressures, as well as peripheral vascular resistance, were significantly lower after COH therapy (p=0.001, 0.002, <0.001, <0.001, 0.040, and <0.001, respectively). In contrast, there was no statistically significant difference observed in heart rate, pulse pressure, or cardiac output. The pulse wave velocity measurement was significantly lower after COH than the baseline levels [5.3 m/s (4.5-6.9 m/s) versus 5.4 m/s (4.7-7.3 m/s,); p<0.001], but the augmentation index was not significantly different [28% (4%-41%) versus 29% (5%-43%); p=0.090]. When the patients were grouped according to the occurrence of a pregnancy after IVF therapy, all parameters were not different between the pregnancy (+) and pregnancy (-) patients (p>0.05).Arterial stiffness and hemodynamic parameters significantly decreased in IVF patients who underwent COH therapy. The long-term clinical significance of this short-term effect should be investigated with prospective studies. There was no significant difference in all parameters before and after COH when the pregnancy (+) and pregnancy (-) patients were compared.

P1830 Single-beat aortic arch pulse wave velocity by dual-gate simultaneous Doppler technique: a novel method for arterial stiffness evaluation

Abstract Background Guidelines recommend increased aortic stiffness as a negative prognostic factor to be considered in primary and secondary prevention. Pulse wave velocity (PWV) is a frequently employed surrogate marker of aortic stiffness. Carotid-femoral PWV is the most common index in research and clinical practice, but recently several velocity-encoded magnetic resonance imaging (MRI) techniques have been used for the evaluation of regional aortic arch PWV, where the stiffness seems to be particularly relevant from a prognostic point of view. Purposes. We developed a new ultrasound method for the assessment of aortic arch PWV, using a single-beat dual-gate simultaneous pulsed wave Doppler tracing. The aim of the study is to evaluate the feasibility of this new technique in a group of healthy volunteers. Methods We examined 126 healthy volunteers (81 females, 45 males, mean age 42 + 15 years, range 13-83 years) using a commercially available machine equipped with simultaneous dual-gate pulsed Doppler. Using the suprasternal approach, the first sample volume was placed in ascending aorta and the second one in descending aorta. The distance between the two sites was directly measured with a curvilinear tracing in the middle of the vessel, following the shape of the aortic arch. PWV was calculated as the ratio of distance (in millimiters) and the transit time (in milliseconds) measured using the "foot-to-foot" method. The results are then easily transformed, simplifying in the commonly unit of meters/second. Results Feasibility was 99%; in one case it was not possible to measure accurately the aortic arch PWV due to unfavorable suprasternal acustic window. The procedure time was very fast, requiring 2 + 1 minutes. Intraobserver and interobserver variability were 7% and 9% respectively. Aortic arch PWV, as expected, showed a strong correlation with age in males as well as in females (r= 0.71 and r = 0.60 respectively, p &amp;lt; 0.001 for both); there was also a significant correlation with body mass index (r = 0.31; p &amp;lt; 0.001). Aortic arch PWV values ranged from 3.1 to 8.5 m/s, showing a substantial overlap with normal values reported in MRI studies. Conclusions The direct measurement of aortic arch PWV is feasible and reproducible with ultrasound, using the novel single-beat dual-gate simultaneous pulsed wave Doppler tracing. This technique could be implemented in a standard echo examination, that is much more available than MRI studies. Further studies are needed to evaluate if Doppler-derived aortic arch PWV could provide additional prognostic information. Abstract P1830 Figure. Aortic Arch PWV