... with classic OH populations. autonomic failure orthostatic hypotension polyneuropathy syncope Various Valsalva metrics have been reported to be useful in characterizing the severity of adrenergic dysfunction and were measured in the present study ( Figure 2 ). These include the magnitude...

...-body negative pressure (LBNP) until pre-syncope to inflict hypotension. End-tidal carbon dioxide was clamped at baseline levels (isocapnic trial) or uncontrolled (poikilocapnic trial). Middle cerebral artery (MCA) and posterior cerebral artery (PCA) blood velocities (transcranial Doppler; TCD), heart...

..., and that vasodepression would be exaggerated by head-up tilt. We performed pulse contour analyses on blood pressure recordings during CSM in syncope patients during supine rest and head-up tilt. In a subset we simultaneously recorded muscle sympathetic nerve activity supine. During supine rest, systolic blood pressure...

... beneficial effects on IOH. All patients had a clinical diagnosis of IOH based on a consistent history of (pre-)syncope occurring 5–15 s after rising from a supine or squatting position. There was no classic orthostatic hypotension [i.e. ΔSBP >20 mmHg and/or ΔDBP (diastolic BP) >10 mmHg at 3 min...

... eliminated in the occluded leg, as there was still a column of blood from the foot to the site of occlusion in the thigh. Alternatively, the increase resulted from drift of the plethysmograph signal. autonomic nervous system orthostasis syncope strain gauge plethysmography venous compliance venous...

...) with syncopal episodes shortly after rising from prolonged recumbence. In 1932, Sir Thomas Lewis also referred to IOH (initial orthostatic hypotension) in his classical lecture on vasovagal syncope, writing “There is another and frequent form of giddiness occasionally leading up to syncope, which is due...

...Giosuè GULLI; Victoria L. COOPER; Victoria CLAYDON; Roger HAINSWORTH 12 11 2002 26 2 2003 2 4 2003 2 4 2003 © 2003 The Biochemical Society 2003 baroreflex heart rate variability syncope vasovagal syndrome Correspondence: Dr Giosuè Gulli (e...

...Julian M. STEWART; Amy WELDON Simple faint (neurocardiogenic syncope) and postural tachycardia syndrome (POTS) characterize acute and chronic orthostatic intolerance respectively. We explored the hypothesis that vascular function is similar in the two conditions. We studied 29 patients with POTS...

...Elisabeth BELLARD; Jacques-Olivier FORTRAT; Daniel SCHANG; Jean-Marc DUPUIS; Jacques VICTOR; Georges LEFTHÉRIOTIS We determined whether early changes in central haemodynamics, as determined by transthoracic impedance, induced by a 70° head-up tilt (HUT) test could predict syncope. Heart rate...

... responses on approach of an orthostatic faint is wide in the young. 8 1 1997 20 5 1997 © 1997 The Biochemical Society and the Medical Research Society 1997 cardiac output hypotension orthostasis syncope teenagers vasomotor system Clinical Science (1997) 93,205-21 I (Printed...

... and the Medical Research Society 1996 blood pressure hypotension stroke volume syncope Clinical Science (1996) 91, 193-200 (Printed in Great Britain) I93 Finger arterial versus intrabrachial pressure and continuous cardiac output during head-up tilt testing in healthy subjects Wilbert T. JELLEMA, Ben...

... hypotension. 2. Postprandial hypotension is a common disorder of blood pressure regulation in the elderly, associated with falls and syncope. The pathophysiological mechanism is thought to be related to impaired vascular compensation for splanchnic blood pooling after a meal. Since caffeine inhibits...

...J. Timothy Lightfoot; Stuart A. Rowe; Suzanne M. Fortney 1. To determine whether activation of the left ventricular C-fibre mechanoreceptors initiates the vasodepressor reflex that often causes syncope, we exposed six orthotopic cardiac transplant patients and six matched, healthy control subjects...

...M. M. A. E. Wahbha; C. A. Morley; Y. M. H. Al-Shamma; R. Hainsworth 1. This study was undertaken to determine whether, in a group of patients complaining of recurrent syncopal attacks but with no apparent cause, there was evidence of abnormal cardiovascular reflex control. 2. The steady-state...

...B. J. Robinson; R. H. Johnson 1. Syncopal or near syncopal episodes have been observed in five subjects who stood or were tilted and in whom blood samples were being taken. 2. In all subjects bradycardia and hypotension developed before the onset of symptoms. Increases in plasma adrenaline...

.... A striking increase of arginine vasopressin concentration was seen within 4 min of syncope, but there was no change of plasma osmolality, cortisol concentration or renin activity. 30 12 1975 © 1976 The Biochemical Society and the Medical Research Society 1976 plasma volume posture renin...