BACKGROUND: In patients with end-stage renal disease pulse wave velocity (PWV) has been widely assessed, but its behavior in mild to moderate chronic kidney disease (CKD) has been less investigated. We evaluated PWV in mild to moderate CKD. METHODS: We studied 31 patients with grade II-IV CKD. Aortic PWV (aPWV), ...

Central pulse pressure is more likely to reflect the haemodynamic conditions to which the heart and coronary arteries are subjected than is peripheral pulse. We reviewed the data currently available on the correlations between central pulse pressure and both the presence and extent of coronary artery disease, as well as ...

BACKGROUND: The coronary artery calcification (CAC) score determined by multi-detector row computed tomography (MDCT) predicts the onset of coronary artery disease (CAD). In addition, pulse wave velocity (PWV) also predicts the mortality of CAD. Therefore, the aim of this study was to assess whether or not the CAC score is ...

BACKGROUND: In young ADPKD patients, we have previously found an impaired endothelium-dependent relaxation in small resistance vessels but a normal flow-mediated dilatation of the brachial artery. The present study investigated arterial stiffness in early ADPKD by pulse-wave analysis (PWA) and measurement of pulse-wave velocity (PWV). METHODS: 18 young normotensive ADPKD ...

"Arterial blood pressure analysis based on scattering transform I" introduces a new method based on the scattering transform for a one dimensional Schrödinger equation to reconstruct the arterial blood pressure waves and separate its systolic and diastolic parts. In this article, we propose to analyse the parameters computed from this ...

Pulse pressure (PP) is traditionally believed to increase cardiovascular risk because of an increase in afterload leading to left ventricular hypertrophy. It has also been emphasized that low diastolic blood pressure, being in part responsible for high PP, leads to an impairment of myocardial perfusion with all its adverse consequences. ...

A theoretical study has been performed to assess how the pulse pressure variation affects results of the arterial compliance measurement. Two asymmetric arctangent models for the arterial pressure-volume (P-V) relationship have been used by applying model-based and amplitude-based compliance estimation techniques. The results demonstrate that for near-zero transmural pressure the ...

OBJECTIVES: This observational study was conducted to compare the significance of the relationship between arterial stiffness and progression to higher blood pressure categories among middle-aged Japanese men with high normal blood pressure (HNP), normal blood pressure (NRP) and optimal blood pressure (OPP). METHODS AND RESULTS: During the 3-year observational period, ...

Arterial blood pressure and velocity pulse wave speed are important biomarkers of arterial stiffness and cardiovascular disease risk in man. Arterial wave speed is usually assessed using pulse wavefront movement over a known finite portion of the arterial tree. In our pilot study we assess a new technique for determining ...

INTRODUCTION: Pulse pressure is a potent risk factor for atherosclerotic disease. The purpose of this cross-sectional study was to determine whether pulse pressure is associated with blood coagulation and fibrinolysis in patients with diabetes. MATERIALS AND METHODS: The relationships between pulse pressure and atherosclerotic risk factors, including blood coagulation and ...

This article presents a new method for analyzing arterial blood pressure waves. The technique is based on the scattering transform and consists in solving the spectral problem associated to a one-dimensional Schrödinger operator with a potential depending linearly upon the pressure. This potential is then expressed with the discrete spectrum ...

Pulse pressure is known to be a potent risk factor for cardiovascular disease. However, it has not been determined whether pulse pressure is associated with cerebrovascular disease in patients with diabetes mellitus. The purpose of the present study was to investigate association of pulse pressure with carotid atherosclerosis in patients ...

Wave intensity (WI) is a hemodynamics index, which is the product of changes in pressure and velocity across the wave-front. Wave Intensity Analysis, which is a time domain technique allows for the separation of running waves into their forward and backward directions and traditionally uses the measured pressure and velocity ...

OBJECTIVE: To estimate the repeatability of radial pulse wave analysis (PWA) in measuring central systolic and diastolic blood pressures (cSBP/cDBP), pulse pressure (cPP), augmentation pressure (cAP) and pulse pressure amplification (PPA). METHODS: After 15 min supine rest, 20 ambulant patients (aged 27-82 years; four female) underwent four SphygmoCor PWA measurements ...

Conduit arteries become stiffer with age due to alterations in their morphology and the composition of the their major structural proteins, elastin and collagen. The elastic lamellae undergo fragmentation and thinning, leading to ectasia and a gradual transfer of mechanical load to collagen, which is 100-1000 times stiffer than elastin. ...

Brachial pulse pressure (PP) is an established risk marker for cardiovascular disease. PP is largely determined by the stroke volume in young subjects, although the progressive amplification of pulse wave from central to peripheral arteries could make brachial PP not representative of the central PP in the young. With advancing ...

A technique for calibrating non-invasive peripheral arterial sensor signals to peripheral arterial blood pressure (BP) is proposed. The adaptive system identification method utilizes a measurable intra-arterial hydrostatic pressure change in the sensor outfitted appendage to identify the transduction dynamics relating the peripheral arterial blood pressure and the measured arterial sensor ...

Systemic inhibition of nitric oxide (NO) synthesis raises blood pressure, and endothelial dysfunction with reduced NO bioactivity is a precursor of atherosclerosis. Pre-hypertensive blood pressures place patients at increased risk for cardiovascular morbid events. Whether NO deficiency contributes to this increased risk has not been explored. Constitutive NO release was ...

The nonlinear parameter B/A, better know as the Beyer parameter, is a measure of the nonlinearity between variations of the pressure and density. Because of these variation propagating wave is distorted. Media with the different Beyer parameter, will distort wave differently. In our work we are trying to measure this ...

BACKGROUND: Cardiovascular mortality is high in hemodialysis (HD) patients. Early arterial pressure wave reflections, reflecting arterial stiffness and the endogenous nitric oxide synthesis inhibitor asymmetric dimethylarginine (ADMA) levels predict mortality in HD patients. Therefore, we aimed to study changes in ADMA levels and central arterial pressure waveform during HD. METHODS: ...

A non-invasive wrist sensor, BPGuardian (Empirical Technologies C., Charlottesville, VA) has been developed that provides continuous pressure readings by de-convolving the radial arterial pulse waveform into its constituent component pulses (Pulse Decomposition Analysis). Results agree with the predictions of the model regarding the temporal and amplitudinal behavior of the component ...

Indices obtained from the second derivative of the digital volume pulse waveform have been proposed to characterize vascular aging, arterial rigidity, and the effects of vasoactive drugs. The purpose of this study was to assess the effects of manual needling of PC6 on SD(DVP) indices in healthy and untreated hypertensive ...

Blood pressure is a complex phenomenon that can be divided into two components: a steady and a pulsatile component. The pulsatile component is estimated by the pulse pressure which is mainly influenced by the large artery stiffness. The purpose of this review was to describe the relation between pulse pressure, ...

Arterial pressure variability is a relatively unexplored topic among the various and detailed studies of cardiovascular variability. A deeper analysis of components and contributions carried by diastolic and pulse pressure may provide a unique insight on the potential systemic effects due to vasomotor activity and response at the level of ...

OBJECTIVES: The aim of this study was to investigate the changes of regional tissue Doppler velocity after volume removal following regular hemodialysis (HD) in uremic patients. Is tissue Doppler velocity really preload-independent? BACKGROUND: Diastolic dysfunction was divided into four stages: normal pattern, abnormal relaxation pattern, pseudonormalization pattern, and restrictive pattern. ...

This chapter traces the history of nitroglycerin from the initial nitration of glycerol to its widespread clinical use. The pharmacologic differences between nitroglycerin and nitric oxide are described, as well as their similar mechanisms of action. The vasoactivity of nitroglycerin requires a biochemical transformation, the nature of which remains incompletely ...

To investigate the role of infrasound aortic pressure waves (IPW) in atherosclerotic plaque rupture. Atherosclerotic plaques have been simulated partly, in two dimensions, as being short or long Conical Intersections (CIS), that is to say elliptic, parabolic or hyperbolic surfaces. Consequently, the course and reflection of the generated aortic pressure ...

OBJECTIVE: Aortic stiffness and wave reflections are important markers and prognosticators of cardiovascular risk. Caffeine increases acutely aortic stiffness and wave reflections. Furthermore, chronic coffee consumption is associated with increased aortic stiffness and wave reflections in normotensive subjects. In the present study, we aimed to assess the association between chronic ...

Earlier work of wave dissipation in flexible tubes and arteries has been carried out predominantly in the frequency domain and most of the studies used the measured pressure waveform for presenting the results. In this work we investigate the pattern of wave dissipation in the time domain using the separated ...

A new optical device was developed that measures blood pressure noninvasively, in small human subjects (neonates and premature infants) and small animals (Roeder RAR. Transducer for indirect measurement of blood pressure in small human subjects and animals, Purdue University, BME; 2003.: xi, 50 p.). The ability of this device to ...

BACKGROUND: Whether arterial stiffness per se contributes to left ventricular hypertrophy (LVH) independently of blood pressure (BP) remains unknown. We examined the relationship between pulse wave velocity (PWV) and LVH in a large population. METHODS: The PWV was measured between the brachial and ankle regions (baPWV) of 798 individuals. We ...

In the present study, we compared indices of respiratory-induced variation obtained from direct arterial blood pressure measurement with analogous indices obtained from the plethysmogram measured by the pulse oximeter to assess the value of these indices for predicting the cardiac output increase in response to a fluid challenge. Thirty-two fluid ...

Blood pressure (BP) is one of the most important contributing factors to pulse wave velocity (PWV), a classic measure of arterial stiffness. Although there have been many non-invasive studies to show the relation between arterial stiffness and BP, the results are controversial. The aim of this study is to evaluate ...

The left atrium (LA) acts as a booster pump during late diastole, generating the Doppler transmitral A wave and contributing incrementally to left ventricular (LV) filling. However, after volume loading and in certain disease states, LA contraction fills the LV less effectively, and retrograde flow (i.e., the Doppler Ar wave) ...

The effect of ambient pressure on the interaction between a laser plasma bubble and a shock wave involving a Richtmyer-Meshkov instability was experimentally studied via framing Schlieren visualization. A sharp plasma interface could be formed without any separation material that causes undesired disturbances. The fundamental vortex structure which was produced ...

We analyzed ventilation-induced changes in arterial blood pressure and photoplethysmography from waveforms obtained by monitoring 57 patients in the operating room and intensive care unit. Analysis of systolic and pulse pressure variations during positive pressure ventilation, DeltaUp, DeltaDown, and changes in the preejection period on both arterial and photoplethysmographic waveforms ...

BACKGROUND: Since thermoneutral head-out water immersion induces an increase in central blood volume and cardiac output along with a decrease in peripheral vascular resistance, we examined here whether thermoneutral immersion leads rapidly to an increase in arterial compliance. METHODS: Changes in hemodynamic status and arterial compliance induced by thermoneutral head-out ...

Arterial wall stiffness can be associated with various diseases. The stiffness of an artery can be measured with the pulse wave velocity (PWV) using the "foot-to-foot" method. However, the foot of the pressure pulse is not very clear, due to reflected waves. The blood pressure pulse generated by the heart ...

Arterial injury resulting from the interaction of contrast agent (CA) with ultrasound (US) was studied in rabbit auricular arteries and assessed by histopathologic evaluation and s-thrombomodulin concentrations. Three sites on each artery were exposed (2.8 MHz, 5-min exposure duration, 10-Hz pulse repetition frequency, 1.4-mus pulse duration) using one of three ...

BACKGROUND: It was previously reported that the intracranial pulse pressure amplitudes were elevated in idiopathic normal pressure hydrocephalus (iNPH) patients responding to shunt surgery. In this study, pulse pressure amplitudes were determined in all patients referred for tentative iNPH, and patients were selected for shunt surgery based on the determination ...

Hemodialysis (HD) has been associated with an increase in the amplitude of QRS complexes. Experience in a single patient with multiple measurements has shown that HD leads also to augmentation of P-wave amplitude. The objective of this investigation was to evaluate electrocardiogram (ECG) changes with HD in a cohort of ...

There is a paucity of data regarding the relation between the various noninvasive indexes of arterial stiffness and left ventricular diastolic function. In 188 subjects aged > or =65 years (mean 75 +/- 5; 71% men), the concordance and strength of the association between measures of arterial stiffness and left ...

By continuous monitoring of abdominal aortic blood pressure via telemetry in conscious rats, we have observed that systolic, diastolic, and pulse pressures of male Brown-Norway rats were all significantly lower than that of male Wistar-Kyoto rats, despite the fact that all of the values in both strains were within normotensive ...

OBJECTIVE: Oscillometric noninvasive blood pressure measurement devices determine the pressures by analysing the relationship between the pressure in an occluding cuff and low-amplitude pressure pulses (oscillometric pulses) induced in the cuff by the arterial pressure wave. This paper examines the effects on the pulses and oscillometric pulse amplitude envelope of ...

The pulsatile component of blood pressure (ie, pulse pressure) has received considerable attention as an important risk factor for cardiovascular disease. In particular, central blood pressure measurements in the ascending aorta or in the carotid artery are expected to be more useful than conventional brachial pressure measurements for predicting cardiovascular ...

BACKGROUND: We investigated whether the aortic augmentation index (AIx), a measure of arterial wave reflection and stiffness, is associated with cardiorespiratory fitness in men without known coronary heart disease (CHD). METHODS: Asymptomatic men (n = 201, mean age 51 +/- 9.2 years) referred for a screening exercise electrocardiogram (ECG) underwent ...

Isolated systolic hypertension (ISH) is the dominant form of hypertension in the elderly. It is associated with increased arterial pulse pressure, to which an early-returning and magnified pulse-wave reflection makes an important contribution. Treatment of ISH with diuretics, calcium channel blockers (CCBs), and angiotensin II inhibitors is effective in reducing ...

OBJECTIVE: We have recently shown that mean pulse pressure is higher in patients with transient myocardial ischemia. Pulse pressure elevation might be an important consequence of increased arterial stiffness. The aim of this study was to prove if arterial stiffness is changed in patients with transient myocardial ischemia who bear ...

We report experimental results from a comparative study on collapsed region and conventional region operation of capacitive micromachined ultrasonic transducers (CMUTs) fabricated with a wafer bonding technique. Using ultrasonic pulse-echo and pitch-catch measurements, we characterized single elements of 1-D CMUT arrays operating in oil. The experimental results from this study ...

OBJECTIVES: Previous animal and human experiments have suggested that reduction in central blood volume either increases or decreases the amplitude of R waves in various electrocardiograph (ECG) leads depending on underlying pathophysiology. In this investigation, we used graded central hypovolemia in adult volunteer subjects to test the hypothesis that moderate ...