BACKGROUND: There are almost no reports on the physiological effects of the various electric massage devices available on the market. This report describes the effects on peripheral vascular circulation and autonomic-nervous system activity of a pulse-synchronized air-massage (PS-AM) device in which cuffs apply air pressure cyclically to the lower limbs ...

Tracking changes in stroke volume or cardiac output (CO) can be useful in the diagnosis and treatment of various cardiac illnesses. Existing arterial pressure waveform based pulse contour CO algorithms perform poorly during altered systemic hemodynamics. In this study, a right ventricular pressure waveform based pulse contour CO algorithm was ...

This review offers a critical evaluation of the remarkable progress in antihypertensive therapy since its inception. Despite the introduction of newer, more sophisticated drugs, treatment results have remained stable. Problems impeding further improvement include limited patient compliance, clinical inertia, incomplete adherence to guidelines, and dependence on brachial artery cuff pressures ...

Pulsatile arterial hemodynamics in cardiovascular diseases indicate that the aortic blood pressure curve may be represented by 2 different phenotypes: one in patients 64 years old and younger and the other in subjects older than 65 years. The 2 blood pressure curves may have exactly the same mean arterial pressure ...

OBJECTIVES: To determine if arterial properties and wave reflection characteristics are favorably altered after enhanced external counterpulsation (EECP) treatment in patients with refractory angina. BACKGROUND: Early return of reflected waves from the lower body, resulting from increased arterial stiffness, augments central aortic pressure and increases left ventricular (LV) afterload and ...

Arterial stiffness is an independent predictor of mortality and is regulated by a number of factors, including vascular smooth muscle tone. However, the relationship between endothelial function and definitive measures of arterial stiffness and wave reflections has not been described in healthy individuals. Therefore, we tested the hypothesis that endothelial ...

Wave reflections affect the proximal aortic pressure and flow waves and play a role in systolic hypertension. A measure of wave reflection, receiving much attention, is the augmentation index (AI), the ratio of the secondary rise in pressure and pulse pressure. AI can be limiting, because it depends not only ...

The volumetric pulses in the finger PPG signal appear as an information source for several indirect measurement methods. In this study we modelled transformation of pressure pulses into volume pulses in a wide transmural pressure range. The noninvasive finger arterial pressure and photoplethysmographic (PPG) signals were simultaneously registered in 13 ...

OBJECTIVE: The aim of this study was to evaluate whether there is a relationship between aortic elastic properties and diurnal blood pressure rhythm in hypertensive subjects. METHODS AND RESULTS: This study included 41 hypertensive patients who were taking medical treatment and had undergone ambulatory blood pressure monitoring (ABPM). The patients ...

The ubiquitous brachial cuff method gained widespread clinical acceptance for blood pressure recording after confirmation of its prognostic value in 1917. This method displaced radial pulse waveform analysis by sphygmography, which also gave prognostic Information but was difficult to use. Since that time, brachial cuff sphygmomanometry has migrated from the ...

Pulse wave velocity is a reliable marker of arterial compliance. Stiffness of large and elastic arteries leads to a faster propagation of pulse wave. The aim of this study was to evaluate changes in arterial distensibility using antihypertensive drugs. This treatment focused on the inhibition of the renin-angiotensin-aldosterone system and ...

Endothelin-1 stimulates collagen synthesis and is increased in hypertension, but its effect on collagen degradation remains unknown. The current study tested the hypothesis that elevated endothelin-1 levels are associated with decreased collagenase activity, markers of collagen degradation, and arterial compliance in hypertensive patients. Normotensive (n = 10) and hypertensive (n ...

Analysis of the contour of the peripheral pulse to assess arterial properties was first described in the nineteenth century. With the recognition of the importance of arterial stiffness there has been a resurgence of interest in pulse wave analysis, particularly the analysis of the radial pressure pulse acquired using a ...

The well recognized cardiac effects of severe hyperkalemia include progressive rhythm and conduction disturbances such as bradycardia, spiked and narrow T waves, widening QRS complex, widening and flattening P wave, disappearance of the P wave, and cardiac arrest. Paradoxically, a heart rate greater than 200 beats/min may coexist with hyperkalemia ...

BACKGROUND: Changes in the vessel lumen diameter pulse waveform closely follow changes in the transmural pressure pulse waveform. AIM: To study diameter pulse waveform recorded noninvasively from the fetal inferior vena cava (IVC) in fetuses with cardiac abnormality. STUDY DESIGN: A paired ultrasonic phase-locked echo tracking system with a high ...

AIMS: Endothelial function is characteristically impaired in patients with hypertension. Endothelial function was assessed in men and women with hypertension using a recently described, non-invasive method. METHODS: Twenty patients and 20 controls received salbutamol 400 microg and glyceryl trinitrate (GTN) 500 microg in a two-way randomized, single-blind study. Effects on ...

BACKGROUND AND OBJECTIVES: Sumatriptan, a 5-hydroxytryptamine (HT)(1B/1D) receptor agonist, is an effective acute antimigraine drug. Because of its vasoconstrictor activity, it is contraindicated in patients at high risk for adverse cardiovascular events. Acute antimigraine drugs without vasoconstrictor effects are currently being developed, and sensitive, noninvasive techniques by which to detect ...

BACKGROUND: The problems of patients with erectile dysfunction have been recognized, leading to the emergence of sildenafil, which has led to successful treatment in many cases. The purpose of this study is to examine the effect of sildenafil on the pulse wave velocity of patients with erectile dysfunction. METHODS: Fifteen ...

Brachial-ankle pulse wave velocity is a new measure of arterial stiffness. The clinical significance of brachial-ankle pulse wave velocity as a measure of early vascular damage remains unclear. We examined the hypothesis that higher brachial-ankle pulse wave velocity is associated with a much greater risk of albuminuria by employing a ...

Quantitative analysis of the arterial pressure pulse waveform recorded by applanation tonometry of the radial artery can track NO (nitric oxide)-mediated modulation of arterial smooth muscle tone. The changes in pressure pulse waveform morphology result from pulse wave reflection arising predominantly from smaller arteries and arterioles. Employing Doppler ultrasound to ...

Periodic pulses of intense ultrasound energy at 70 kHz with 5-ms duration at 3 MPa SPL applied to the exposed pig myocardium at physiologic rhythms were observed to produce cardiac pacing. Ten animals were successfully paced at pulse width and energy conditions above a certain threshold. Sigmoid strength-duration curves characterizing ...

Once considered part of the normal aging process, the development of isolated systolic hypertension represents a late manifestation of increased arterial stiffness in older people. Furthermore, isolated systolic hypertension is the single most frequent subtype of hypertension in the US adult population. Indeed, central arterial stiffness rather than peripheral vascular ...

Arterial stiffness is an independent cardiovascular prognostic factor and is modulated by angiotensin-converting enzyme inhibitors (ACEIs). The authors performed a meta-analysis of clinical trials investigating the effects of ACEIs on pulse wave velocity (PWV) or augmentation index. The search included randomized clinical trials as well as uncontrolled studies that measured ...

Noninvasive finger blood pressure has become a surrogate for central blood pressure under widely varying circumstances. We tested the validity of finger-aorta transfer functions (TF) to reconstruct aortic pressure in seven cardiac patients before, during, and after incremental bicycle exercise. The autoregressive exogenous model method was used for calculating finger-aorta ...

OBJECTIVE: To correlate the values in the basic blood pressure groups presented in the JNC 7th with the computed values of the Noninvasive Hemodynamic Analyzer (NHA) and to demonstrate the pathophysiological alterations by three proportional hypertensive models. DESIGN: Hemodynamic values of each of the blood pressure groups presented in the ...

BACKGROUND: We review the accepted primary blast injury criteria. We point out a significant systematic error in the criteria due to the use of low-quality pulse duration data in the original criteria. METHODS: We recalculate the injury criteria using state-of-the-art blast data. RESULTS: We give the corrected injury criteria in ...

OBJECTIVES: Isoflavones reduce arterial stiffness, a predictor of cardiovascular events. Whether metabolites of isoflavones have similar bioactivity is unknown. The effect of supplemental trans-tetrahydrodaidzein (THD) a metabolite of daidzein on pulse wave velocity (PWV), a measure of arterial stiffness was tested in overweight men and postmenopausal women. METHODS: 25 subjects, ...

A large central compliance is thought to dominate the hemodynamics of all vertebrates except birds and mammals. Yet large crocodilians may adumbrate the avian and mammalian condition and set the stage for significant wave transmission (reflection) effects, with potentially detrimental impacts on cardiac performance. To investigate whether crocodilians exhibit wave ...

Pulse transit time (PTT) is a simple, noninvasive technique which shows great promise in the continuous monitoring of blood pressure and the assessment of arterial stiffness, and has potential applications in wearable healthcare devices. Usually, PTT is measured from the electrocardiogram (ECG) R-wave to a characteristic point on the peripheral ...

BACKGROUND: Chronic kidney disease (CKD) is a risk factor for future cardiovascular disease. Although pulse wave velocity (PWV), which reflects arterial stiffness, was increased in subjects with CKD, little is known regarding whether renal function is associated with PWV in a low-risk population and whether proteinuria and decreased renal function ...

Isolated systolic hypertension is an important cardiovascular risk factor in the elderly. In addition to systolic blood pressure, pulse pressure, pulse wave velocity, and carotid wave reflections are also strong cardiovascular risk factors in the elderly, as a consequence of the two main determinants of systolic hypertension: increased arterial stiffness ...

OBJECTIVE: To determine the effects of hemorrhage on wave-reflection-induced systolic pressure augmentation in the aorta. DESIGN: Randomized, controlled laboratory experiment. SETTING: University research laboratory. SUBJECTS: Twenty-five anesthetized pigs randomized to surgical controls (n = 7), hemorrhage (n = 9, H), and hemorrhage with reinfusion (n = 9, HR). INTERVENTIONS: Hemorrhage ...

The objective of the present study was to examine the relationship between markers of inflammation, such as high-sensitivity C-reactive protein (hsCRP) and erythrocyte sedimentation rate (ESR), and brachial-ankle pulse wave velocity (baPWV), an indicator of arterial stiffness, in Japanese men. We studied 269 male subjects (mean age, 53 years) who ...

Although arterial stiffness is an independent cardiovascular risk factor associated with both aging and hypertension, relatively little is known regarding the structural changes in the vessel wall that occur with vessel stiffening. We determined if collagen type-I metabolism is related to arterial stiffening in both hypertensive and normotensive subjects. Arterial ...

To measure the stiffness of the aorta, femoral artery and tibial artery noninvasively, cardio-ankle vascular index (CAVI) which is independent of blood pressure was developed. The formula for measuring this index is; CAVI=a{(2rho/DeltaP) x ln(Ps/Pd)PWV(2)} + b where, Ps and Pd are systolic and diastolic blood pressures respectively, PWV is ...

Isolated systolic hypertension (ISH) is an important cause of strokes and heart failure among the elderly, but it is difficult to control in some elderly patients, even with combination antihypertensive therapy. The presence of a prominent reflection wave in the arterial pulse-wave profile of such patients signifies that adjuvant nitrate ...

OBJECTIVE: In the process of determining oxygen saturation, the pulse oximeter functions as a photoelectric plethysmograph. By analyzing how the frequency spectrum of the pulse oximeter waveform changes over time, new clinically relevant features can be extracted. METHODS: Thirty patients undergoing general anesthesia for abdominal surgery had their pulse oximeter, ...

OBJECTIVES: Endografting is being used to manage aneurysms, dissections and acute traumatic disruptions of the thoracic aorta. The acute effects of such interventions on ventricular afterload and on pressure wave transmission characteristics are not well known. METHODS: In five dogs, a 55 mm endograft was introduced into the descending aorta, ...

AIM: Our aim was to determine how the risk associated with presence of low transcutaneous oxygen tension (tcPO2) for subsequent major amputation in patients with skin ulcers or gangrene and peripheral arterial disease, compares with the risks associated with low peripheral pressures and low amplitude of pulse waves. Secondly, we ...

AIM: The purpose of this study was to examine the effects of a cycle competition on the large arteries stiffness, 24-hours after the end of the effort. METHODS: Two males elite cyclists were studied before and after performing a stage-race. Their heart rate (HR) was measured continuously during the two ...

Pulse wave velocity (PWV), the carotid augmentation index (AIx), and pulse pressure (PP) may be prognostic factors in heart failure, but the possible influence of the ejection fraction (EF) and other simple haemodynamic variables on them has not been investigated in this setting. Noninvasive methods were used to measure carotid-radial ...

The "hemodynamic inverse problem" is the determination of arterial system properties from pressures and flows measured at the entrance of an arterial system. Conventionally, investigators fit reduced arterial system models to data, and the resulting model parameters represent putative arterial properties. However, no unique solution to the inverse problem exists-an ...

BACKGROUND: Various factors are implicated in the circadian pattern of cardiovascular vulnerability. The exact mechanisms involved in the peak incidence of cardiovascular events occurring during the early morning hours after awaking are not completely known. The purpose of our study was to investigate the circadian variation of timing and intensity ...

Increasing attention has been focused on the pathophysiology and prognostic relevance of increased pulse pressure. High systolic pressure increases vascular load whereas low diastolic pressure reduces coronary perfusion presssure, both of which provide pathophysiological explanations for the prognostic value of pulse pressure. In a recent study we have demonstrated that ...

OBJECTIVE: Large-artery stiffness and arterial wave reflections have been identified as independent markers and prognosticators of cardiovascular risk. Mental stress is a novel risk factor for coronary artery disease and has been associated with left ventricular dysfunction, myocardial ischemia and infarction, and sudden cardiac death. The purpose of this study ...

A clinical method for monitoring cardiac output (CO) should be continuous, minimally invasive, and accurate. However, none of the conventional CO measurement methods possess all of these characteristics. On the other hand, peripheral arterial blood pressure (ABP) may be measured reliably and continuously with little or no invasiveness. We have ...

Arterial wall stiffness can be associated with various diseases. Arteriosclerosis involves the buildup of plaques within artery walls that stiffen the arteries. The stiffness of an artery can be assessed by measurement of the pulse wave velocity (PWV). Usually, PWV is estimated using the foot-to-foot method. However, the foot of ...

We hypothesized that 1 minus the slope of diastolic on systolic pressure during 24-hour ambulatory monitoring (ambulatory arterial stiffness index [AASI]) might reflect arterial stiffness. We compared AASI with established measures of arterial stiffness and studied its distribution in Chinese and European populations. We used 90207 SpaceLabs monitors and the ...

Early return of reflected pressure waves increases the load on central arteries and may increase the risk of aortic rupture in patients with Marfan's syndrome (MFS). To assess whether wave reflection is elevated in MFS, we used ultrasound and MRI to measure central pressure and flow waveforms in 26 patients ...

Interactions between paced wavefronts and monomorphic ventricular tachycardia (VT) dictate antitachycardia pacing outcomes. Monomorphic VTs were initiated in isolated rabbit hearts (n=6) that were endocardially cryoablated to limit viable tissue to the visible epicardium and the ablated apex served as an anatomic anchor. Preparations were optically mapped during single and ...