Search results for "wave"
showing 10 items of 6009 documents
Arterial Destiffening in Previously Untreated Mild Hypertensives After 1 Year of Routine Clinical Management
2016
BACKGROUND Arterial stiffness, measured with pulse wave velocity (PWV), is now classified as a marker of target organ damage (TOD) alongside left ventricular hypertrophy and moderately increased albuminuria. Interventional studies on treated hypertensive patients have shown that PWV could be improved. Our aim was to assess changes in arterial stiffness after 1 year of routine clinical practice in never-treated hypertensive patients. PATIENTS AND METHODS We studied 356 never-treated patients with suspected hypertension. After standard clinical assessment during which presence of TOD was evaluated, hypertension diagnosis was confirmed in 231 subjects who subsequently received standard routine…
Wave similarity mapping shows the spatiotemporal distribution of fibrillatory wave complexity in the human right atrium during paroxysmal and chronic…
2005
Introduction: The complexity of waveforms during atrial fibrillation may reflect critical activation patterns for the arrhythmia perpetuation. In this study, we introduce a novel concept of map, based on the analysis of the wave morphology, which gives a direct evidence in the human right atrium on the spatiotemporal distribution of fibrillatory wave complexity in paroxysmal (PAF) and chronic (CAF) atrial fibrillation. Methods and Results: Electrograms were recorded from a 64-electrode catheter in the right atrium of 15 patients during PAF (n = 8) and CAF (n = 7). Wave similarity maps were constructed by calculating the degree of morphological similarity of activation waves (S) at each atri…
Long term follow up of patients with chronic pancreatitis and pancreatic stones treated with extracorporeal shock wave lithotripsy
1999
BACKGROUNDThere have been conflicting reports as to whether pancreatic ductal drainage achieved by endoscopy and lithotripsy improves the clinical outcome of patients with chronic pancreatitis.AIMSTo determine the clinical outcome in patients with chronic pancreatitis who received extracorporeal shock wave lithotripsy (ESWL), and were followed up for two to eight years.METHODSEighty patients with severe chronic pancreatitis and endoscopically unretrievable obstructive stones underwent ESWL with a piezoelectric lithotripter between 1989 and 1996. Clinical status, relief of symptoms, further endoscopic or surgical interventions, and mortality were defined.RESULTSForty three (54%) patients wer…
Pulse pressure amplification and its determinants
2015
Background. Pulse pressure (PP) amplification expressed as the peripheral-to-central PP ratio has gained importance in the assessment of cardiovascular phenotypes and cardiovascular risk. The aim of the present study was to assess the relationship between PP amplification, large vessel parameters and peripheral blood pressure (BP) to gain insights into the amplification phenomenon. Methods. Peripheral BP, central BP and carotid-femoral pulse wave velocity (cfPWV) were assessed using the OMRON M6, SphygmoCor and Complior devices, respectively, in 741 adults attending the hypertension outpatient clinic. Analysis of covariance, partial correlations and multiple linear regression models were pe…
The INTERPHONE study: design, epidemiological methods, and description of the study population
2007
The very rapid worldwide increase in mobile phone use in the last decade has generated considerable interest in the possible health effects of exposure to radio frequency (RF) fields. A multinational case-control study, INTERPHONE, was set-up to investigate whether mobile phone use increases the risk of cancer and, more specifically, whether the RF fields emitted by mobile phones are carcinogenic. The study focused on tumours arising in the tissues most exposed to RF fields from mobile phones: glioma, meningioma, acoustic neurinoma and parotid gland tumours. In addition to a detailed history of mobile phone use, information was collected on a number of known and potential risk factors for t…
No short-term effects of digital mobile radio telephone on the awake human electroencephalogram
1997
A recent study reported the results of an exploratory study of alterations of the quantitative sleep profile due to the effects of a digital mobile radio telephone. Rapid eye movement (REM) was suppressed, and the spectral power density in the 8–13 Hz frequency range during REM sleep was altered. The aim of the present study was to illuminate the influence of digital mobile radio telephone on the awake electroencephalogram (EEG) of healthy subjects. For this purpose, we investigated 34 male subjects in a single-blind cross-over design experiment by measuring spontaneous EEGs under closed-eyes condition from scalp positions C3 and C4 and comparing the effects of an active (0.05 mW/cm2) and a…
Effects of REM sleep awakenings and related wakening paradigms on the ultradian sleep cycle and the symptoms in depression.
2002
In 1975 Vogel and coworkers published their classical study where they compared selective rapid eye movement (REM) sleep deprivation by brief awakenings to a control intervention paradigm in depressed patients. The superior antidepressive impact of the first procedure was attributed to the REM pressure accumulating during the treatment period. The laborious procedure and the considerable effort necessary to evaluate the sleep profiles in real time have prevented similar experiments so far. Based on artificial neural networks we developed a software for the real time detection of REM sleep. In combination with an alarm system the algorithm allowed us to wake up subjects automatically and to …
Relationships between mild hyperuricaemia and aortic stiffness in untreated hypertensive patients.
2013
Background and aims: Clinical studies exploring the relationship between serum uric acid (SUA) and arterial stiffness yielded conflicting results. Only in a few of these studies, arterial distensibility was examined by measuring aortic pulse wave velocity (PWV), which is considered the gold standard for evaluating arterial stiffness. In none of the previous investigations was the influence of SUA on aortic distensibility assessed, taking into account the effect of albuminuria. The purpose of our study was to comprehensively analyse the relationships between SUA and aortic PWV in a group of essential hypertensive patients. Methods and results: We enrolled 222 untreated and uncomplicated hype…
Association of renal resistive index with aortic pulse wave velocity in hypertensive patients
2014
Background: Recent data suggest that renal haemodynamic parameters obtained by duplex Doppler sonography, especially the intrarenal resistive index (RI), may be associated with systemic vascular changes. However, conflicting data exist about the independent relationship between aortic stiffness and RI. The aim of this study was to evaluate the relationship between RI and arterial stiffness, assessed by aortic pulse wave velocity (aPWV), in hypertensive patients. Design: Cross-sectional study. Methods: We enrolled 264 hypertensive subjects aged between 30 and 70 years. They were divided into two groups, either with normal renal function (n=140) or with chronic kidney disease (CKD) (n=124). E…
Variable association of 24-h peripheral and central hemodynamics and stiffness with hypertension-mediated organ damage: the VASOTENS Registry.
2020
Objective In this analysis of the telehealth-based Vascular health ASsessment Of The hypertENSive patients Registry, we checked how 24-h central and peripheral hemodynamics compare with hypertension-mediated organ damage (HMOD). Methods In 646 hypertensive patients (mean age 52 ± 16 years, 54% males, 65% treated) we obtained ambulatory brachial and central SBP and pulse pressure (PP), SBP, and PP variability, pulse wave velocity and augmentation index with a validated cuff-based technology. HMOD was defined by an increased left ventricular mass index (cardiac damage, evaluated in 482 patients), an increased intima-media thickness (vascular damage, n = 368), or a decreased estimated glomerul…