Pulse Wave Velocity Parameters Research Articles

ASSOCIATIONS BETWEEN ADHERENCE TO THE MEDITERRANEAN DIET AND 24-HOUR PULSE WAVE VELOCITY IN HYPERTENSIVE PATIENTS

Objective: A Mediterranean diet (MeDi) is characterized by high consumption of plant-based food and fish, moderate consumption of red wine, and low intake of red and processed meat, and is associated with improvement in cardiometabolic risk factors. Arterial stiffness measured by pulse wave velocity (PWV) is considered a predictor of cardiovascular events, but the association between dietary intake according to MeDi and arterial stiffness is not yet clear. The aim of this study was to determine possible associations between MeDi adherence and PWV in patients with arterial hypertension (AH). Design and method: This study included 420 participants with AH of which 50.2% were women, with an overall median age of 63.5 years (IQR = 17.3). To assess 24-hour PWV parameter, a 24-hour ambulatory blood pressure monitor IEM Mobil-O-Graph based on the oscillometry was used. In order to determine adherence to the MeDi, a validated Mediterranean Diet Serving Score (MDSS) questionnaire was used. For every participant, data about comorbidities was collected from their medical records combined with their self reports. Results: Adherence to the MeDi defined as MDSS score >14 was found in 6.4% of participants. The mean value of 24-hour PWV was 9.08±1.88 m/s. Significant differences in PWV value were not found among high adherence, medium adherence and low adherence to MeDi. Positive predictors of 24-hour PWV were older age (beta = 0.128, p<0.001), presence of chronic kidney disease (beta = 0.312, p<0.001) and adherence to the legumes intake recommendation (beta = 0.169, p = 0.037), while the negative predictor was adherence to the dairy intake recommendation (beta = -0.174, p = 0.024). Conclusions: Exceptionally low adherence to the principles of the MeDi was noticed in hypertensive patients, with dairy and legumes suggested as predictors of 24-hour PWV. This suggests a need for structural nutritional intervention to increase adherence to the MeDi in order to decrease and reduce cardiovascular risk in this population of patients.

Non-invasive assessment of ventricular-arterial coupling: correlation between myocardial work and the pulse wave velocity parameters

Úvod: MěřenĂ­ prĂĄce myokardu (myocardial work, MW) představuje novou echokardiografickou metodu zaloĹženou na sledovĂĄnĂ­ smyčky tlak-deformace srdečnĂ­ komory, coĹž umoŞňuje kvantifikovat vĂ˝konnost srdce. Na druhĂŠ straně rychlost pulsnĂ­ vlny (pulse wave velocity, PWV) určuje tuhost tepen na zĂĄkladě poznatku, Ĺže se zvyĹĄujĂ­cĂ­ se tuhostĂ­ tepny se zvyĹĄuje i rychlost anterogrĂĄdnĂ­ho a retrogrĂĄdnĂ­ho přenosu sfygmickĂŠ vlny. CĂ­l: CĂ­lem tĂŠto studie bylo stanovit korelaci mezi parametry MW a PWV. Metody: Do studie jsme zařazovali vĹĄechny po sobě nĂĄsledujĂ­cĂ­ pacienty bez kardiovaskulĂĄrnĂ­ho onemocněnĂ­, kteří v obdobĂ­ mezi červnem 2021 a červencem 2022 absolvovali transtorakĂĄlnĂ­ dopplerovskĂŠ echokardio- grafickĂŠ vyĹĄetřenĂ­. Hodnoty MW byly vypočítĂĄny ze smyčky tlak-deformace srdečnĂ­ komory, do nĂ­Ĺž byly začleněny hodnoty neinvazivnĂ­ho vyĹĄetřenĂ­ tepennĂŠho tlaku podle doporučenĂ­ pro standardnĂ­ echokardiogracfickĂŠ vyĹĄetřenĂ­ metodou "speckle tracking". Hodnota PWV se měřila tonometrem na Ăşrovni společnĂŠ karotidy a společnĂŠ femorĂĄlnĂ­ tepny. VĂ˝sledky: Celkem bylo do studie zařazeno 66 pacientĹŻ prĹŻměrnĂŠho věku 30,7 ± 8,6 roku. Byla nalezena statisticky vĂ˝znamnĂĄ negativnĂ­ korelace mezi PWV a celkovou zbytečně vynaloĹženou energiĂ­ (global wasted energy, GWE) (r = -0,317; p < 0,01) při korelaci s celkovou zbytečně vynaloĹženou pracĂ­ (global wasted work, GWW) (r = 0,324; p < 0,01). Statisticky vĂ˝znamnĂĄ korelace přetrvĂĄvala v podskupinĂĄch Ĺžen i muŞů u GWE (Ĺženy: r = -0,280; p < 0,05; muĹži: r = -0,362; p < 0,05) i u GWW (Ĺženy: r = 0,359; p < 0,05; muĹži: r = 0,359; p < 0,05). ZĂĄvěr: Vztah mezi MW a PWV jako projev součinnosti mezi levou komorou a velkĂ˝mi tepnami mĹŻĹže potenciĂĄlně představovat uĹžitečnĂ˝ nĂĄstroj pro časnĂŠ odhalenĂ­ subklinickĂŠ dysfunkce kardiovaskulĂĄrnĂ­ho systĂŠmu. © 2023, ČKS.

Altered heart rate variability and pulse-wave velocity after spinal cord injury.

BACKGROUNDHeart rate variability (HRV) and pulse-wave velocity (PWV), indicators of cardiac function, are altered in patients with spinal cord injury (SCI), suggesting that autonomic cardiac function and arterial stiffness may underlie the high risk of cardiovascular complications in these patients. No study has simultaneously investigated HRV and PWV in the same patients.AIMTo evaluate cardiovascular complications in SCI patients by comparing HRV and PWV between patients with and without SCI.METHODSIn this cross-sectional pilot study, patients with (n = 60) and without SCI (n = 60) were recruited from December 7, 2019 to January 21, 2020. Each participant received a five-minute assessment of HRV and the cardiovascular system using the Medicore HRV Analyzer SA-3000P. Differences in HRV and PWV parameters between participants with and without SCI were statistically examined.RESULTSWe observed a significant difference between participants with and without SCI with respect to the standard deviation of all normal-to-normal intervals, square root of the mean sum of squared successive risk ratio interval differences, physical stress index, total power, very-low frequency, low frequency, high frequency, and arterial elasticity.CONCLUSIONPatients with SCI have weaker sympathetic and parasympathetic activity as well as lower arterial elasticity compared to those without, suggesting that SCI may increase cardiac function loading.

767 Correlations between myocardial work parameters and pulse wave velocity

Abstract Aims The myocardial work (MW) is a new echocardiographic method, based on the pressure–strain loop, which allows to quantify the cardiac performance. On the other hand, the pulse wave velocity (PWV) evaluates arterial stiffness, knowing that as the stiffness of an artery increases, the transmission velocity of the anterograde and the retrograde sphygmic wave increase. The aim of the study is to evaluate the correlation between MW and PWV parameters. Methods and results We enrolled 32 healthy patients (mean age: 39 ± 17 years), who underwent transthoracic Doppler echocardiography (TTE). The MW parameters was derived from the strain–pressure loop, including in its calculation the measurement non-invasive arterial pressure, according to standard speckle tracking echocardiography recommendations. The PWV measurement was obtained by tonometry at the level of the common carotid artery and the common femoral artery. None of the parameters measured was pathological according to the normality studies considered. It was found a linear correlation between PWV and global wasted work (GWW) (linear R2: 0.603; P = 0.001) and an inverse linear correlation between PWC and global work efficiency (GWE) (linear R2: −0.307; P = 0.032). Conclusions The study highlights the possibility of PWV to predict pre-clinical myocardial changes, given the correlation with GWW and the linear inverse correlation with GWE.

Heart-Ankle Pulse Wave Velocity Is Superior to Brachial-Ankle Pulse Wave Velocity in Detecting Aldosterone-Induced Arterial Stiffness.

Primary aldosteronism (PA) is associated with higher arterial stiffness compared to essential hypertension (EH). However, few studies have compared different pulse wave velocity (PWV) parameters to detect aldosterone-induced arterial stiffness. In this study, we aimed to compare the sensitivity in detecting aldosterone-induced arterial stiffness between brachial-ankle PWV (baPWV) and heart-ankle PWV (haPWV). We prospectively enrolled 1006 PA patients and 983 EH patients. Detailed medical history, basic biochemistry data and two PWV measurements (baPWV and haPWV) were collected in both groups. We performed analysis on the original cohort and two propensity score matching (PSM) models (model 1 adjusted for age and sex; model 2 adjusted for age, sex, systolic and diastolic blood pressure). The DeLong test was used to compare areas under receiver operating characteristic curves (AUCs) between baPWV and haPWV to predict PA. In all models, the PA patients had significantly higher baPWV compared to the EH patients. The AUC of haPWV was greater than that of baPWV. In conclusion, haPWV seems to be a better PWV parameter than baPWV in detecting aldosterone-induced arterial stiffness.

Association of vitamin D deficiency with arterial stiffness in newly diagnosed hypertension.

Vitamin D has beneficial effects on vascular endothelial function, blood pressure (BP) and arterial stiffness. Arterial stiffness increases in early-stage hypertensive patients and it is a strong predictor of cardiovascular morbidity and mortality. The purpose of this study was to assess the association between serum 25-hydroxyvitamin D (25-OH D) levels and arterial stiffness in patients with newly diagnosed hypertension. Our study included 100 newly diagnosed hypertensive patients (63 male, 37 female and mean age: 51.7 ± 10.3 years) without cardiovascular disease, malignancy, chronic kidney disease and diabetes mellitus. Patients were divided into two groups: vitamin D deficiency group (<20 ng/ml) and normal vitamin D group (≥20 ng/ml). Twenty-four-hour, daytime and nighttime ambulatory BP readings were recorded. Mobil-O-Graph ARC solver algorithm was used to evaluate arterial stiffness parameters of pulse wave velocity (PWV) (m/s), augmentation index normalized with 75/min heart rate (Alx@75). Patients with vitamin D deficency had higher values of Alx@75 and PWV values (20.9 ± 9 vs. 16.8 ± 6.9, P = 0.018 and 8.37 ± 1.16 vs. 6.9 ± 0.9, P = 0.001, respectively) despite similar 24-hour ambulatory BP monitoring in both groups. Level of serum calcium was significantly higher in vitamin D deficiency group (9.5 ± 0.23 vs. 9.3 ± 0.12, P = 0.007). Nighttime SBP was higher in vitamin D deficiency group (133.2 ± 14.3 mmHg vs. 126.3 ± 17.2 mmHg; P = 0.03) and also, vitamin D deficiency group had non-dipping SBP pattern compared to normal Vitamin D group (P = 0.013). Vitamin D deficiency is associated with increased arterial stiffness in newly diagnosed hypertensive patients in terms of increased PWV and Alx@75 values.

P2642Optimal blood pressure control in relation to target organ physiology in hypertensive men with erectile dysfunction

Abstract Background Target organ damage (TOD) in essential hypertension relates to an adverse prognosis. Middle aged men are considered a population group where cardiovascular risk typically augments and erectile dysfunction (ED) that frequently accompanies both entities refers to a subclinical vascular damage process. Purpose To identify the optimal blood pressure (BP) levels in middle aged hypertensive males with ED in relation to TOD. Methods 258 ED males (mean age: 56 yo) with essential hypertension under medical treatment enrolled the study. All underwent 2D echocardiography and carotid ultrasound evaluation to determine left ventricular mass index (LVMI) and intima – media thickness (IMT) respectively. Carotid – femoral pulse wave velocity (PWV) and augmentation index (AIx) were also assessed as indices of central vascular stiffness and wave reflection physiology (complior &amp; sphygmocor devices). Office brachial blood pressure (BP) measurements where performed according to the current guidelines and an average of three consecutive values was computed. Erectile dysfunction was assessed by using the SHIM-5 score (range 0–25, lower values display a pronounced dysfunction). Results In bivariate analysis brachial systolic blood pressure (bSAP) was positively and strongly associated with LVMI (r=0,6), PWV (r=0,65), AIx (r=0,67, all p&lt;0,001) and IMT (p&lt;0,05, r=0,55). Erectile performance as assessed by the SHIM-5 score was negatively related to PWV, AIX and IMT (r=−0,58, r=−0,45 and r=−0,65 all p&lt;0,001) pointing out the underlying vascular detriment. Interestingly, there were no such correlations regarding the diastolic blood pressure values. Multiple linear regression analysis was performed and the relation of bSAP with LVMI, PWV, AIx and IMT remained significant after adjustment for age, BMI, smoking habits and presence of diabetes mellitus (all p&lt;0,05). We further subdivided our population into three groups according to the values of office bSAP for normal blood pressure (≤129mmHg, n=143,55%), high normal (130–139mmHg, n=59, 23%) and high (≥140mmHg, n=56,22%). In patients with high-normal bSAP, the parameters of PWV and LVMI were significantly higher than in patients with normal BP (independent sample t-test, p: 0,032 and 0,016 respectively). Patients of the high bSAP group as expected, had more extensive cardiac and vascular damage (LVMI, PWV and AIx). Conclusion In essential hypertensive middle aged men with erectile dysfunction, guiding therapy toward normal systolic blood pressure values as compared to the high normal benefits target organ physiology. It is clinically important to identify this vascular patients group in order to adjust regimens and further therapeutic strategies.

Effects of Exercise Training on Endothelial Function, Arterial Structure, and Physical Conditioning in Patients with Systemic Autoimmune Myopathies: A Case Series Study

Introduction. Exercise training has been effective in improving endothelial function and decreasing arterial stiffness in several systemic autoimmune diseases. However, to date, no studies have assessed patients with systemic autoimmune myopathies (SAM). Methods. Five female patients with definite SAM (3 dermatomyositis and 2 polymyositis) who underwent a 12-week, twice-a-week, exercise training program were assessed prospectively. The following parameters were assessed: endothelial function measured by flow-mediated dilatation (FMD), carotid femoral by pulse wave velocity (PWV), disease status by International Myositis Assessment & Clinical Studies Group (IMACS) set score, the ventilatory anaerobic threefold (VAT), respiratory compensation point (RCP), maximum effort (ME), maximal oxygen uptake (VO2max) measured by ergospyrometer, and strength and muscle function. Results. Mean age of the patients and duration of disease were 43.9 and 10.5 years, respectively. The median FMD and PWV were 10.2% and 7.1 m/s. After exercise training, important FMD reduction was observed in 4 out of 5 patients, whereas the PWV parameters decreased in only 2 out of 5 patients. The exercise training was safe, without clinical intercurrences or disease relapses. Moreover, an increase in strength and functionality was observed. Concerning aerobic capacity, there was a decrease in the VAT and an increase in ME, without al-terations in the maximum oxygen consumption. Conclusions. In general, exercise training does not alter endothelial function and PWV values, but improves muscle strength and function and also, does not lead to disease reactivation (Clinical Trials (NCT03092167)).

Parameters of pulse wave velocity: determinants and reference values assessed in the population-based study LIFE-Adult

Aims and backgroundParameters of arterial stiffness such as pulse wave velocity (PWV) were recently proposed as independent risk factors of cardiovascular events. We analyse three PWV parameters in the large population-based study LIFE-Adult to identify risk factors, normal and reference values.Methods and resultsBrachial-ankle (ba), brachial-femoral (bf) and carotid-femoral (cf) PWV assessment was performed using Vicorder device. 8509 participants aged 19–80 were analysed. PWV parameters were moderately correlated (r(ba/bf) = 0.6, r(ba/cf) = 0.46, r(bf/cf) = 0.59). Age and blood pressure are the dominant determinants of PWV parameters explaining > 18% of variability. Sex was only relevant for bfPWV and cfPWV. All further analysed cardiovascular and other risk factors are of minor importance. We provide age-dependent percentiles for the population (reference values) and for the subgroup of normotonic individuals. All percentiles show a strong increase with age. The difference between normotonic and all individuals is small for younger age groups but increases up to 1 m/s for elderly subjects.ConclusionOur study confirms and further underpins the strong impact of age and blood pressure on arterial stiffness and the relatively weak contribution of other factors, supporting an independent role of arterial stiffness in cardiovascular disease development. Age-dependent reference and normal values were provided on the basis of the so far largest study sample facilitating the implementation of PWV assessment in clinical practice. Due to better compliance, handling and stronger association with age and blood pressure, baPWV could serve as an alternative to cfPWV. Follow-up data are required to estimate the clinical significance of specified PWV cut-offs.

Arterial stiffness and 25-hydroxyvitamin D levels in chronic kidney disease patients

Arterial stiffness refers to arterial wall rigidity, particularly developing in central vessels. Arterial stiffness increases in early stage chronic kidney disease (CKD), and it is a strong predictor of cardiovascular and all cause mortality. Vitamin D has beneficial effects on blood pressure, vascular endothelial function and arterial stiffness. 25-hydroxyvitamin D (25(OH)D) deficiency is quite common worldwide and in the CKD population. We aimed to evaluate the prevalence of 25(OH)D deficiency and its relation with arterial stiffness in CKD. Our study included 101 patients (51 male, 50 female), with stages 3B-5 CKD not on dialysis. A single-cuff arteriograph device (Mobil-O-Graph) was used to evaluate arterial stiffness parameters of pulse wave velocity (PWV) and augmentation index (Alx@75). The patients were divided into two groups: group I vitamin D non-deficient [25(OH)D > 15 ng/mL] and group II vitamin D deficient [25(OH)D ≤ 15 ng/mL]. Overall, the mean 25(OH)D level was 14.1±7.9 ng/mL and 70 patients (69.4%) were vitamin D deficient. The mean Alx@75 value was significantly higher in group II (28.6±10.8% vs. 23.3±13.5%, p=0.038). PWV was higher in group II, but the difference was not significant. Group II exhibited significantly lower serum albumin (p<0.001), hemoglobin (p=0.005), calcium (p=0.041) and estimated glomerular filtration rate (eGFR) (p=0.041), but significantly higher 24-hour proteinuria (p=0.011) and more females (p=0.006). Vitamin D was negatively correlated with Alx@75 augmentation pressure, parathyroid hormone, proteinuria and body mass index, and positively correlated with albumin, hemoglobin, eGFR, calcium and transferrin. 25(OH)D was independently associated with Alx@75 (beta=-0.469, p=0.001) and albumin (beta=0.447, p=0.002). In CKD patients 25(OH)D deficiency was common, particularly in females. Level of 25(OH)D was independently associated with Alx@75.

Contribution of volume overload to the arterial stiffness of hemodialysis patients

Arterial stiffness is evaluated with the measurement of pulse wave velocity (PWV), while overhydration (OH) and nutritional status are evaluated with bioimpedance spectroscopy (BIS). In this study, we investigated the effect of a single dialysis session on arterial stiffness, hydration status, and laboratory parameters. The observational, cross-sectional, cohort study included 71 HD patients with mean age 64 ± 16 yrs. A Complior device was used to perform PWV measurements. The patients were examined immediately before and 15 min after a mid-week hemodialysis session. Body fluids and nutritional status were studied using a Body Composition Monitor (BCM), Fresenius Medical Care. Clinical and laboratory data were also analyzed. Multivariate regression analysis of PWV before HD showed that an OH increase of 1 L relate to a PWV parameter rise before HD of 0.523 m/s. Multivariate regression analysis of PWV after HD showed that a rise of central SBP after HD of 10 mmHg relate to a PWV increase after HD of 0.707 m/s. Our data indicate that hydration status and blood pressure may be major determinants of PWV in HD patients.

PP.06.31

Objective: As previously reported, calibration mode significantly affects the reliability of central hemodynamic data measured by noninvasive brachial cuff-based blood pressure (BP) monitoring device, Mobil-O-Graph®. This device can also evaluate pulse wave velocity (PWV) that is regarded as a marker for arterial stiffness such as atherosclerosis, which as well needs calibration. But it is unknown which calibration mode is better for predicting coronary heart disease. The aim of this study was to compare the predicting value of PWV attained by Mobil-O-Graph® (mogPWV) between two available calibration modes in Japanese cardiovascular patients. We also compared the same way between mogPWV with brachial-ankle PWV (baPWV). Design and method: We enrolled 138 patients who underwent elective coronary angiography for suspected coronary artery disease. Significant coronary artery disease (sCAD) was defined to have at least one stenosis over 50% or history of coronary angioplasty. Prior to angiography, we measured mogPWV and calculated mogPWV1 and mogPWV2 through calibration with systolic/diastolic and mean/diastolic BP, respectively. With logistic regression analysis, we evaluated the contribution of these PWV parameters for the presence of sCAD. In selected 121 patients, we also measured baPWV and analyzed same way. Results: Two mogPWV values well correlated with each other (correlation coefficient:0.97, p < 0.001), but differed significantly (mogPWV1: 10.1 ± 2.1 m/s, mog PWV2: 11.1 ± 2.4 m/s; p < 0.01). We found markedly higher baPWV than mogPWVs (baPWV:17.9 ± 3.9 m/s). Next we evaluated the relative risk of PWV indices for sCAD. In univariate logistic regression analysis, mogPWV1 and mogPWV2 were associated with sCAD, whereas baPWV was not. In multivariate analysis, only mogPWV2 remained significant after adjusting traditional risk factors and other potential confounders (odds ratio: 1.25 [1.00–1.56]; p < 0.05). Conclusions: In utilizing a brachial Pulse Wave Analysis-Based monitoring device, PWV calibrated with mean/diastolic BP better predicts the presence of significant coronary artery disease in Japanese cardiovascular patients.

102 Ethnic differences in endothelial function in chronic heart failure

<h3>Background</h3> Endothelial dysfunction is characteristic of patients with heart failure (HF) and is associated with an increased risk of future cardiovascular events. However, data on ethnic differences in endothelial function in HF are scarce. In this study we aimed to compare parameters of macro- and micro-vascular endothelial function and arterial elasticity in HF age- and sex-matched patients of different ethnic origin: (i) white European, (ii) south Asian and (iii) African-Caribbean. Additionally, SA patients with systolic HF were compared to two matched control groups: (i) south Asian patients with coronary artery disease without HF(disease controls)and (ii) south Asian “healthy controls”. <h3>Methods</h3> We recruited 186 age/sex-matched patients with HF (ejection fraction &lt;40%) of SA (n=43, age 66.5±11.1 years), white (n=44, age 68.4±9.4 years) and African-Caribbean (n=21, age 69.2±10.3 years) origin; as well as 36 disease controls (age 64.0±10.6 years) and 40 healthy controls (n=40, age 63.3±9.24 years). Macrovascular endothelial function was assessed as brachial artery flow mediated dilation in response to hyperaemia (FMD) and glyceryltrinitrate were assessed by vascular ultrasonography (iE33, Philips, USA). Microvascular endothelial function was evaluated by laser Doppler flowmetry of forearm skin (DRT4, Moor Instruments, UK) after iontophoresis of acetylcholine and sodium nitroprusside. Arterial stiffness was quantified by pulse wave velocity and augmentation index using (Sphygmocor, Australia). <h3>Results</h3> Compared to disease controls and healthy controls south Asian patients with HF had impaired microvascular response to acetylcholine (390±302%, 549±264%, and 123±95.5%, respectively, p&lt;0.05) and reduced FMD (7.12±3.64%, 11.8±4.66%, and 4.86±4.88%, respectively). HF patients of south Asian origin had impaired microvascular endothelial function (response to acetylcholine123±95.5%) compared to white (258±15.6%) and African-Caribbean (286±17.3%) groups (p&gt;0.05). HF patients of white origin had higher FMD than south Asian (4.86±4.88%) and African-Caribbean (5.36±3.24%) patients (p&lt;0.05). No difference in glyceryltrinitrate- and sodium nitroprusside-mediated (endothelial-independent) response was observed between study groups. In south Asian subjects, parameters of pulse wave velocity and augmentation index did not differ between those with HF and those in control groups. No ethnic differences were detected in pulse wave velocity. Conclusion: South Asian patients with HF have impaired micro- and macro-vascular endothelial function, but preserved arterial elastic properties. Significant ethnic differences in endothelial function are present in patients with HF.

Pulse‐wave morphology and pulse‐wave velocity in healthy human volunteers: Examination conditions

Objective. Applanation tonometry for pulse‐wave analysis (PWA) and determination of pulse‐wave velocity (PWV) is a non‐invasive method for assessment of the central aortic pressure waveform and indices of arterial stiffness. The objective of this study was to examine the influence of eating and smoking on PWA and PWV measurements in order to establish standard examination conditions. Furthermore, intra‐ and interobserver reproducibility and the effects of varying the site of measurements were observed. Material and methods. Duplicate measurements of the radial pressure waveform and of the brachial and aortic PWV on the right and left side of the body were recorded in 23 healthy subjects by two trained observers. Measurements were performed in the fasting state and 3 h after a high‐calorie meal, and before and 1 h after smoking a cigarette. Results. Intake of a high‐calorie meal as well as smoking caused significant changes in both PWA and PWV parameters and an inter‐arm difference was observed. Intra‐ and interobserver reproducibility was good. Conclusions. Pulse‐wave measurements by applanation tonometry should be undertaken in the same arm during fasting and smoking abstinence.

Signal analysis of the hemodynamics of extracorporeal circulation for the evaluation of patient status

The present paper describes the intra-operative evaluation of circulation dynamics during open-heart surgery, with the aim of providing the anaesthetist with objective data for assessing patient status during the procedure. For this purpose, the parameters pulse wave velocity and biological impedance were used. With the aid of these parameters it is possible, in the extracorporeal model, to detect different kinds of stenosis, volume losses, vessel dilatation and vessel constriction. In addition, the influence of arteriosclerosis on circulation dynamics was investigated. The assignment of the parameters to various events is effected using a "decision tree" and a neural network. Finally, the technique is verified using data obtained from animal experiments.