Arterial Stiffness

A new oscillometric method for assessment of arterial
stiffness: comparison with tonometric and piezo-electronic
methods
Johannes Baulmanna, Ulrich Schillingsb, Susanna Rickertb, Sakir Uenb,
Rainer Du¨ singb, Attila Czirakic, Miklos Illyesc and Thomas Mengdenb
Introduction Pulse wave velocity (PWV) and augmentation
index (AIx) are parameters of arterial stiffness and wave
reflection. PWV and AIx are strong indicators for
cardiovascular risk and are used increasingly in clinical
practice. Previous systems for assessment of PWV and AIx
are investigator dependent and time consuming. The aim of
this study was to validate the new oscillometric method
(Arteriograph) for determining PWV and AIx by comparing it
to two clinically validated, broadly accepted tonometric and
piezo-electronic systems (SphygmoCor and Complior).
Design and method PWV and AIx were measured up to five
times in 51 patients with the SphygmoCor, Complior and
Arteriograph. In 35 patients, the measurements were
repeated after 1 week in a second session using the
same protocol.
Results The correlations of the PWV as assessed with the
Arteriograph with the values obtained using the
SphygmoCor (rU0.67, P < 0.001) and the Complior
(rU0.69, P < 0.001) were highly significant. Variability and
reproducibility for PWV were best for the Arteriograph

Arterial Stiffness

Assessment of arterial stiffness in hypertension: comparison of oscillometric (Arteriograph), piezoelectronic (Complior) and tonometric (SphygmoCor) techniques.
Noor A Jatoi, Azra Mahmud, Kathleen Bennett, John Feely
Department of Pharmacology and Therapeutics, Trinity College Centre for Health Sciences and Hypertension Clinic, St. James's Hospital, Dublin, Ireland.
Journal of hypertension (impact factor: 4.02). 10/2009; 27(11):2186-91. DOI:10.1097/HJH.0b013e32833057e8
Source: PubMed
ABSTRACT Arterial stiffness, measured as aortic pulse wave velocity (PWV), and wave reflection, measured as augmentation index (AIx), are independent predictors for total and cardiovascular morbidity and mortality. The aim of this study was to compare a new device

Arterial Stiffness

Clin Cardiol. 2012 Jan;35(1):26-31. doi: 10.1002/clc.20999. Epub 2011 Nov 14.
Comparison of aortic and carotid arterial stiffness parameters in patients with verified coronary artery disease.
Gaszner B, Lenkey Z, Illyés M, Sárszegi Z, Horváth IG, Magyari B, Molnár F, Kónyi A, Cziráki A.
Source
Heart Institute, Faculty of Medicine, University of Pécs, Hungary.
Abstract
BACKGROUND:
Arterial stiffness parameters are commonly used to determine the development of atherosclerotic disease. The independent predictive value of aortic stiffness has been demonstrated for coronary events.
HYPOTHESIS:
The aim of our study was to compare regional and local arterial functional parameters measured by 2 different noninvasive methods in patients with verified coronary artery disease (CAD). We also compared and contrasted these stiffness parameters to the coronary SYNTAX score in patients who had undergone coronary angiography.
METHODS:
In this study, 125 CAD patients were involved, and similar noninvasive measurements were performed on 125 healthy subjects. The regional velocity of the aortic pulse wave (PWVao) was measured by a novel oscillometric device, and the common carotid artery was studied by a Doppler echo-tracking system to determine the local carotid pulse wave velocity (PWVcar). The augmentation index (AIx), which varies proportionately with the resistance of the small arteries, was recorded simultaneously.
RESULTS:
In the CAD group, the PWVao and aortic augmentation index (Alxao) values increased significantly (10.1 ± 2.3 m/sec and 34.2% ± 14.6%) compared to the control group (9.6 ± 1.5 m/sec and 30.9% ± 12%; P < 0.05). We observed similar significant increases in the local stiffness parameters (PWVcar and carotid augmentation index [Alxcar]) in patients with verified CAD. Further, we found a strong correlation for PWV and AIx values that were measured with the Arteriograph and those obtained using the echo-tracking method (r = 0.57, P < 0.001 for PWV; and r = 0.65, P < 0.001 for AIx values).
CONCLUSIONS:
Our results indicate that local and regional arterial stiffness parameters provide similar information on impaired arterial stiffening in patients with verified CAD.
© 2011 Wiley Periodicals, Inc.

Arterial Stiffness

Am J Hypertens. 2013 Aug 31. [Epub ahead of print]
Invasive Validation of Arteriograph Estimates of Central Blood Pressure in Patients With Type 2 Diabetes.
Rossen NB, Laugesen E, Peters CD, Ebbehøj E, Knudsen ST, Poulsen PL, Bøtker HE, Hansen KW.
Author information
• Department of Medicine, Silkeborg Regional Hospital, Silkeborg, Denmark.
Abstract
BACKGROUND:
Central blood pressure (BP) has attracted increasing interest because of a potential superiority over brachial BP in predicting cardiovascular morbidity and mortality. Several devices estimating central BP noninvasively are now available. The aim of our study was to determine the validity of the Arteriograph, a brachial cuff-based, oscillometric device, in patients with type 2 diabetes.
METHODS:
We measured central BP invasively and compared it with the Arteriograph-estimated values in 22 type 2 diabetic patients referred to elective coronary angiography.
RESULTS:
The difference (invasively measured BP minus Arteriograph-estimated BP) in central systolic BP (SBP) was 4.4±8.7mm Hg (P = 0.03). The limits of agreement were ±17.1mm Hg.
CONCLUSIONS:
Compared with invasively measured central SBP, we found a systematic underestimation by the Arteriograph. However, the limits of agreement were similar to the previous Arteriograph validation study and to the invasive validation studies of other brachial cuff-based, oscillometric devices. A limitation in our study was the large number of patients (n = 14 of 36) in which the Arteriograph was unable to analyze the pressure curves. In a research setting, the Arteriograph seems applicable in patients with type 2 diabetes.
CLINICAL TRAIL REGISTRATION:
ClinicalTrials.gov ID NCT01538290.
KEYWORDS:
blood pressure, brachial cuff-based, oscillometric devices for measurement of central BP, cardiovascular disease, cardiovascular risk, central blood pressure (BP), diabetes, hypertension, invasive validation of brachial cuff-based, oscillometric devices noninvasive measurement of central BP.

Arterial Stiffness

ALL ABOUT ARTERIES © - ARTERIOGRAPH
Breakthrough in Early Diagnosis of Arteriosclerosis
The TensioClinic Arteriograph analyses the cardiovascular system from five highly important aspects to assure Comprehensive Cardiovascular Risk Assessment. Measuring Central and Peripheral Blood Pressure, Arterial Stiffness (PWV & AIx), Cardiac fitness and considering Classical Cardiovascular Risk Stratification (Framingham, SCORE), Arteriograph enables detecting the real, individual risk even at the early, reversible stage. Numerous EU references are available for reinforcing the significance of this unique screening device, which is also ideal for evaluating the efficiency of applied cardiovascular therapy and for follow up of diabetic patients, too.

Arterial Stiffness

Arterial Stiffness Analysis

There are various methods for cardiovascular examination. The ECG shows signs of oxygen deprivation, when coronaries are blocked for 70% or more. Other invasive procedures such as cardiac catheterization will detect abnormalities at an earlier stage, but such tests are only performed if people have complaints.

The AORTOGRAM is performed with the Arteriograph®. This is a relatively new method that is so sensitive, that abnormalities can be detected in a very early stage .

The Arteriograph measures both the loss of arterial functioning and arterial stiffening.

Loss of function is expressed in the unit AIX: the Augmentation Index. The AIX is a measure of the total resistance of all blood vessels. Against this resistance, the heart pumps every stroke. The higher this resistance is, the higher the work load for the heart. An increased resistance of the blood vessels is caused by loss of function of the endothelium.

Loss of elasticity (stiffness) of the arteries is expressed in the unit of measure PWV: Pulse Wave Velocity, or the speed at which the aortic pulse is going. In case of aortic stiffening the speed of the pulse increases. The higher the PWV, the more stiffening of the aorta has already occurred.

Both loss of function and stiffening are categorized in four groups:

Arterial Stiffness

Validation of Arteriograph – A New Oscillometric Device to Measure Arterial Stiffness in Patients on Maintenance Hemodialysis
Nemcsik J. • Egresits J. • El Hadj Othmane T. • Fekete B.C. • Fodor E. • Szabó T. • Járai Z. • Jekkel C. • Kiss I. • Tislér A.
Kidney Blood Press Res 2009;32:223–229 (DOI: 10.1159/000228935)
Abstract
Background: Measuring arterial stiffness (augmentation index (AI), aortic pulse wave velocity (PWV)) in hemodialysis (HD) patients has prognostic significance. To assess its validity, the new oscillometric Arteriograph device (AIA, PWVA) was compared to the validated PulsePen tonometer (AIP, PWVP). Methods: AI and PWV were measured in 98 patients with both devices before HD. Validity was evaluated by Pearson’s correlation, Bland-Altman analysis, and by assessing the prognostic value of AI and PWV to predict cardiovascular (CV) mortality over 29 months. Results: Correlation between AIP and AIA was significant (R = 0.527, p < 0.001). The mean difference of AI values obtained by the two devices was –20.6%, and 30% of the paired AI differences fall outside the ±1 SD boundary of the mean between-device difference. There was no significant correlation between the PWVP and PWVA readings (R = 0.173, p = 0.097). The average difference of PWV values by the two devices was –1.2 m/s, and 20.6% of the paired PWV differences fall outside the ±1 SD boundary. In survival analyses, only PWVP but not PWVA was significantly related to CV mortality. Conclusion: Lack of correlation between PWVP and PWVA and lack of prognostic significance of PWVA suggest limited validity of Arteriograph to determine PWV in patients on HD.

Arterial Stiffness

Smoking and Hypertension Associated With Greater Arterial Stiffness in People Aging With HIV
By Fred Furtado
From TheBodyPRO.com
November 8, 2013
Having HIV is not independently associated with arterial stiffness -- a trait linked to cardiovascular disease risk -- despite HIV-infected individuals having a modest, but clinically significant, increase in arterial stiffness when compared to their uninfected counterparts. Instead, factors such as smoking and hypertension may account for the increase, according to study results presented at EACS 2013 in Brussels, Belgium.
To provide some background, HIV infection has been associated with an increased risk of cardiovascular disease and one of the markers for this condition is arterial stiffness, which is measured by pulse wave velocity (PWV), or how fast blood moves through the circulatory system. With age, or other changes to the arterial wall, blood vessels become stiffer and blood moves faster through the system, giving the heart less time to rest. PWV is directly dependent on mean arterial pressure (MAP) and past research has shown that an increase of 1 m/s (meter per second) in PWV is associated with a 14% greater incidence in total cardiovascular events.
However, studies measuring PWV in HIV-infected patients have been small and their results inconsistent. So, researchers led by Katherine Kooij, M.D., compared PWV in a cohort of HIV-infected and HIV-uninfected people to determine if there is an independent association between HIV and PWV, as well as possible determinants of PWV.
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The study included 566 HIV-infected and 511 HIV-uninfected individuals, all 45 or older. Both groups had comparable median ages (52.8 versus 52), gender distribution (89.1% men versus 86% men) and proportion of men who have sex with men (76.4% versus 71.4%). However, the HIV-infected group included more current smokers (32.9% versus 24.8%) and users of antihypertensive drugs (31.3% versus 22.4%). The HIV-infected participants also displayed higher levels of inflammation and immune activation markers, such as hs-CRP and sCD163.
The researchers performed three measurements of PWV, as well as systolic and diastolic blood pressure, using an Arteriograph system, which registers oscillometric pressure waves in the aorta through an upper arm cuff. Additional information on potential determinants of arterial stiffness was collected with laboratory measurements and questionnaires. The data underwent a statistical analysis with multivariable linear regression models using PWV as a dependent variable, adjusted for MAP.
The analysis revealed a slightly higher, but significant unadjusted PWV in HIV-infected individuals than in HIV-uninfected individuals (7.9 m/s versus 7.7 m/s, P = .004). When these results were adjusted for MAP and gender, the difference between the two remained at 0.19 m/s (P = .04). If compared to a PWV increase due to age (+0.29 m/s per 5 years older, P < .001), having a positive HIV status would be the equivalent of being 3 to 3.5 years older.
However, when the PWV values were adjusted for other factors, such as smoking and use of antihypertensive drugs, HIV-infected status was no longer independently associated with arterial stiffness. In this setting, the difference between HIV-infected and HIV-uninfected PWV was only 0.022 m/s (P = .8). In contrast, every 5 pack-years (smoking 20 cigarettes a day per year, about 7,305 cigarettes) for current smokers accounted for a difference of 0.121 m/s (P < .001), while use of antihypertensive drugs represented an increase of 0.527 m/s (P < .001). The researchers also found that the inflammation marker hs-CRP and the monocyte activation marker sCD163 were associated with a higher PWV: 0.039 m/s (P = .001) and 0.056 m/s (P = .04), respectively. But sCD163 was only a significant determinant in men.

Arterial Stiffness

The Arteriograph is a diagnostic instrument which is able to measure the severity of arteriosclerosis. This is the condition of arterial blockage caused by inflammation or damage within arteries followed by an over production of a compound known as plaque created by the body to repair the damage. Plaque is made up of cholesterol, minerals such as calcium, specialised red blood cells known as platelets and other clotting factors.

The Arteriograph is a simple and painless, non invasive investigation that can diagnose arteriosclerosis at an early stage .

Symptoms of arterial blockage include chest pain from blocking heart arteries, or the loss of sensation, numbness, or cramp in the lower limbs as the leg arteries block. These symptoms tend not to occur until a considerable amount of an artery is blocked and other arteries are no longer able to offer effective collateral circulation. Symptoms of cardiovascular disease leading to heart attacks and strokes usually appear only in the last and late stages and so arterial disease remains unrecognised through most of its development. The importance of identifying diseased arteries is clear.


Conventional testing

Current investigations are not designed to detect early occlusion of blood vessels. The Gold Standard exercise or stress ECG (where an individual is placed on a running track with leads on their chest attached to the ECG), will not necessarily change until 70% of a coronary (heart) artery is blocked. More sensitive investigation such as angiography are invasive and demand radiation through x-rays and the injection of a 'dye' to show up the arteries. About 1 in 500 angiographies cause serious or even fatal events and this figure is even higher if you take patients who have chest symptoms. These methods of investigation are effective only in diagnosing late stage disease and can carry risks.

The results of the Arteriograph closely correlate to the invasive tests specifically the Coronary Calcium Score and afore mentioned Coronary Angiography with the advantage of avoiding the adverse events.


Statistics involving arterial disease

Arteriosclerosis is the cause of 40% of premature mortality. It is the main cause of heart attacks and strokes and can begin at the age of 20 although the consequences generally appear in our sixth decade. If we were able to diagnose early stage disease we would reduce these negative figures and the Arteriograph, taking only a few minutes and measuring both small and large artery resistance (the medical term for flexibility) is a sensible and valid method of testing the entire arterial system.

Approximately 48,000 people between the age of 30-69 have a heart attack each year here in the UK and 150,000 people suffer a stroke.



The Arteriograph

An individual simply has to avoid food for 3 hours prior to the test and should not drink alcohol for 10 hours nor have any caffeine for 6 hours. You shouldn’t be smoking anyway but that should not happen for at least 3 hours as well! Supplements and drugs that influence blood pressure should not be stopped unless authorised by your GP or prescribing doctor. Most such medication in most people can be stopped for a few days without any longer term risk allowing a clear indication of a patient's arterial status.

After lying down without movement and thinking nice thoughts for a few minutes then a blood pressure cuff is inflated around the upper arm for a few seconds. Other than some tightness no other discomfort is felt.

The specialised computer inflates the cuff two or three times as it establishes the measurements and the nurse will also add in some specific details including the length from your neck to the base of your abdomen – the length of your aorta.

The whole process can take as little as 20 minutess

The doctor reading the results will be able to comment on:
• The resistance (flexibilty) of small arteries
• The resistance (flexibility) of large arteries
• The blood pressure in the aorta – Central Blood Pressure
• Cardiac fitness
• Some other more technical parameters that may be of use to your doctors

The results are provided to you (and any practitioners of your choice) with a guide to interpretation.


The benefits of early diagnosis

It is very important to recognise that early diagnosis of arterial disease allows for intervention that is capable of slowing down the progress of arterial disease and at best possibly reverse the condition.

Arterial Stiffness

Invasive validation of a new oscillometric device (Arteriograph) for measuring augmentation index, central blood pressure and aortic pulse wave velocity.
18:59 EDT 12th September 2013 | BioPortfolio
Home » Latest PubMed Articles » Journals » Journal of hypertension » Invasive validation of a new oscillometric device (Arteriograph) for measuring augmentation index, central blood pressure and aortic pulse wave velocity.
Summary of "Invasive validation of a new oscillometric device (Arteriograph) for measuring augmentation index, central blood pressure and aortic pulse wave velocity."

BACKGROUND:
The importance of measuring aortic pulse wave velocity (PWVao), aortic augmentation index (Aix) and central systolic blood pressure (SBPao) has been shown under different clinical conditions; however, information on these parameters is hard to obtain. The aim of this study was to evaluate the accuracy of a new, easily applicable oscillometric device (Arteriograph), determining these parameters simultaneously, against invasive measurements.
METHODS:
Aortic Aix, SBPao and PWVao were measured invasively during cardiac catheterization in 16, 55 and 22 cases, respectively, and compared with the values measured by the Arteriograph.
RESULTS:
We found strong correlation between the invasively measured aortic Aix and the oscillometrically measured brachial Aix on either beat-to-beat or mean value per patient basis (r = 0.9, P < 0.001; r = 0.94, P < 0.001), which allowed the noninvasive calculation of the aortic Aix without using generalized transfer function. Similarly strong correlation (r = 0.95, P < 0.001) was found between the invasively measured and the noninvasively calculated central SBPao; furthermore, the BHS assessment of the paired differences fulfilled the 'B' grading. The PWVao values measured invasively and by Arteriograph were 9.41 +/- 1.8 m/s and 9.46 +/- 1.8 m/s, respectively (mean +/- SD); furthermore, the Pearson's correlation was 0.91 (P < 0.001). The limits of agreement were 11.4% for aortic Aix and 1.59 m/s for PWVao.
CONCLUSION:
Aix, SBPao and PWVao, measured oscillometrically, showed strong correlation with the invasively obtained values. The observed limits of agreement are encouragingly low for accepting the method for clinical use. Our results suggest that the PWVao values, measured by Arteriograph, are close to the true aortic PWV, determined invasively.
Affiliation
aHeart Institute, Medical School, University of Pécs, Pécs, Hungary bDepartment of Cardiology, University of Rome La Sapienza, Polo Pontino, Italy.
Journal Details
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