The venous system is the main determinant of hypotension in patients with vasovagal syncope
|
|
- Karin Gilmore
- 6 years ago
- Views:
Transcription
1 Europace (2006) 8, doi: /europace/eul095 The venous system is the main determinant of hypotension in patients with vasovagal syncope Giuseppe Fucà 1, Maurizio Dinelli 1, Paolo Suzzani 2, Salvatore Scarfò 3, Fabio Tassinari 1, and Paolo Alboni 1 * 1 Division of Cardiology, Ospedale Civile, Cento (Fe), Italy; 2 SEDA, Milano, Italy; and 3 Division of Cardiology, Ospedale del Delta, Lagosanto (Fe), Italy Received 30 May 2005; accepted after revision 27 March 2006; online publish-ahead-of-print 17 August 2006 KEYWORDS Syncope; Haemodynamics; Tilt test Introduction The haemodynamics of vasovagal syncope (VVS) should be investigated during spontaneous episodes but, for obvious reasons, adequate haemodynamic study is practically impossible. Several observations suggest that the hypotension and bradycardia induced by tilt testing (TT) are similar to the spontaneous episodes, 1 4 and tilt-induced syncope is accepted as a model for this condition. 5 It has been widely demonstrated that VVS is secondary to a fall in blood pressure (BP), usually followed by bradycardia due to withdrawal of sympathetic tone; 6 11 however, the genesis of VVS remains unclear. Blood pressure is dependent on total peripheral resistance (TPR) and cardiac output (CO); the latter on stroke volume (SV) and heart rate (HR). In patients with normal hearts, without systolic dysfunction, SV and CO are mainly determined by venous return, whereas the arterial response is mainly manifest as * Corresponding author. Tel: þ ; fax: þ address: p.alboni@ausl.fe.it Aims In patients with vasovagal syncope (VVS), a neural reflex appears the main determinant of hypotension leading to loss of consciousness; whether hypotension is mainly due to involvement of the arterial system or the venous system remains a debated issue. The aim of the present study was to assess which of these two systems is responsible for the fall in blood pressure (BP) in patients with VVS; to this end, a haemodynamic study was carried out not only before and during loss of consciousness but also during the recovery phase. Methods and results Beat-to-beat recordings of heart rate (HR), BP (volume-clamp method) and stroke volume (SV) (modelflow method), cardiac output (CO), and total peripheral resistance (TPR) were made at rest, during unmedicated tilt testing (TT) and recovery from loss of consciousness in 18 patients with a history of syncope (age years) and positive response to TT. Blood pressure showed a significant fall during prodromal symptoms and a further fall at the beginning of loss of consciousness, together with a fall in SV, CO, and HR, and a slight, but significant, increase in TPR. At the beginning of recovery, BP showed a significant increase and a further increase 5 min later, together with an increase in SV, CO, and HR without significant changes in TPR. Conclusion These results suggest that in VVS the fall in BP is mainly caused by reduced venous return to the heart. The arterial system does not appear to be the main determinant of the fall of BP; however, the system appears unable to make the appropriate compensatory changes. TPR. Certain data suggest that the fall in BP could be related to an impairment of venous return due to inadequate venoconstrictive response during orthostatic or mental stress; other data suggest that the fall in BP could be secondary to inadequate arterial vasoconstriction during orthostatic or physical stress The aim of the present study was to assess whether the fall in BP responsible for the loss of consciousness is mainly due to an inadequate compensatory response of the venous system or the arterial system; to this end, a haemodynamic study was carried out in patients with tilt-induced syncope not only before and during loss of consciousness but also during the recovery phase. Methods Patients referred for the evaluation of syncope were regarded as candidates for the present study if they (i) were aged 18 years; (ii) did not show any sign of cardiological or neurological disease, or arterial hypertension; (iii) had negative carotid sinus massage (not induction of syncope or presyncope during supine or standing & The European Society of Cardiology All rights reserved. For Permissions, please journals.permissions@oxfordjournals.org
2 840 G. Fucà et al. position); (iv) had syncope of unknown origin after the first evaluation; 26 (v) developed syncope associated with hypotension and/ or bradycardia after at least 5 min of unmedicated TT. We selected this time to ensure that we could separate the haemodynamic adjustments during the first 2 min of TT 27 from those that occurred during the minutes before loss of consciousness. From January 2004 to March 2005, 181 patients underwent TT in the out patient clinic and 22 met the eligibility criteria. The study was approved by the Ethics Committee of Cento Hospital. Tilt test protocol The test was always performed in the morning in a quiet room (temperature of C) after overnight fasting without any medication. The procedure was carried out by means of an electronically controlled tilt table with a footboard for weight-bearing. No patient was taking cardioactive medication at the time of the study. After 15 min supine control phase, patients were tilted upright at 608 for 30 min or until syncope, at which time they were immediately tilted back to the horizontal and recorded for a further 15 min. The test was considered positive when it induced syncope associated with hypotension with or without bradycardia. Haemodynamic recording To assess haemodynamic values, Finometer (Finapress Medical Systems, Anhem, The Netherlands) was used; it is a non-invasive monitor to measure beat-to-beat HR and BP by means of the volume-clamp method and the physical criteria developed by Wesseling et al. 28 In addition, the device includes a method (modelflow) to compute aortic flow, SV, CO, and TPR beat-to-beat from an arterial pressure using a three-element model of the arterial input impedance. 29 Total peripheral resistance, expressed in resistance units, was calculated as the quotient of the mean BP and CO. Beat-to-beat registration was made; however, the values of haemodynamic variables were reported as the average of four consecutive cycles just before tilt, after 3 and 5 min of tilt, then, at 5 min intervals, at the beginning of prodromal signs and symptoms as previously described, 30 at the beginning of loss of consciousness, at the beginning of recovery, and 5 and 15 min thereafter. The data from each subject were reviewed manually to remove artefacts. Definitions Syncope was defined as transient loss of consciousness due to diminished cerebral perfusion with inability to maintain postural tone and with spontaneous recovery. Statistical analysis Statistical evaluation of the data was achieved by using paired Student s t-test and the analysis of variance as applicable. Results are expressed as mean + standard deviation. Results Of the 22 patients who met eligibility criteria, four were excluded for technical reasons. The age of the remaining 18 patients was years; 10 were males. The number of spontaneous episodes of syncope was During TT, prodromal symptoms occurred in 17 patients after min and loss of consciousness in all patients after min. The syncopal phase 31 was type 1 (mixed) in 10 patients, type 2A (cardioinhibition without asystole) in four patients, type 2B (cardioinhibition with asystole) in one patient and type 3 (vasodepressor) in three patients. The behaviour of haemodynamic variables is reported in Figures 1 5 and the mean values in Table 1. Figure 1 Systolic, diastolic and mean BP, HR, and SV show a significant decrease at the beginning of the prodrome and a further decrease at the beginning of loss of consciousness. At the beginning of recovery, these variables increase significantly.
3 Venous system: the main determinant of hypotension 841 Figure 2 Cardiac output shows a significant decrease at the beginning of the prodrome and a further decrease at the beginning of loss of consciousness; at the beginning of recovery, this variable increases significantly. Total peripheral resistance remains rather constant, showing a slight but significant increase only before loss of consciousness. Figure 3 From the last scheduled measurement before prodromal symptoms to the beginning of loss of consciousness, SV decreases in all patients and increases in almost all patients at the beginning of recovery.
4 842 G. Fucà et al. Figure 4 In almost all patients, cardiac output decreases from the last scheduled measurement before prodromal symptoms to the beginning of loss of consciousness and increases at the beginning of recovery. Figure 5 Total peripheral resistance shows small changes, with the exception of two older patients showing a marked increase before loss of consciousness.
5 Venous system: the main determinant of hypotension 843 Table 1 The variations of each haemodynamic variable during tilt and the level of significance, by using the analysis of variance, are shown Supine 5 min Before prodrome Beginning Syncope Recovery 5 min post of prodrome recovery 15 min post recovery P-value Systolic BP (mmhg) ,0.001 Diastolic BP (mmhg) ,0.001 Mean BP (mmhg) ,0.001 Heart rate (beats/min) ,0.001 Stroke volume (ml) ,0.001 Cardiac output (L/min) ,0.001 Total peripherial resistance (U) NS Data are reported as mean value + SD. Early tilt test After 3 min of tilt, systolic and mean BP and TPR did not change significantly in comparison with the values recorded in the supine position; diastolic BP and HR increased significantly (P, 0.05 and P, 0.001, respectively) and SV and CO decreased significantly (P, 0.001). The haemodynamic variables did not show significant differences between the third and the fifth minutes of tilt, apart from SV, which decreased significantly (P, 0.05). From the fifth minute of tilt to the last scheduled measurement before prodromal symptoms systolic, diastolic and mean BP and TPR did not change significantly; HR increased (P, 0.05), whereas SV and CO decreased significantly (P, and P ¼ 0.003, respectively). Prodromal symptoms and loss of consciousness From the last scheduled measurement before prodromal symptoms to the beginning of the prodrome, all the variables decreased (systolic, diastolic and mean BP P, 0.001, HR P ¼ 0.004, SV P ¼ 0.004, and CO P, 0.001) with the exception of TPR, which did not change significantly. From the beginning of the prodrome to the beginning of loss of consciousness, all the variables showed a further decrease (systolic BP P, 0.001, diastolic and mean BP P ¼ 0.001, HR P ¼ 0.006, SV P, 0.001, and CO P ¼ 0.002) with the exception of TPR, which increased significantly (P, 0.05). This variable increased markedly in two old patients (75 and 76 years old) with high baseline values (Figure 5). From the last scheduled measurement before prodromal symptoms to the beginning of loss of consciousness, SV decreased in all patients (10%), CO decreased in 17 patients and increased in one; in this patient (21 years old), hypotension was caused by a fall in TPR (from 1.1 to 0.3 U). Total peripheral resistance increased in 10 patients, decreased in five, and remained unchanged in three. Recovery From the beginning of loss of consciousness to the beginning of recovery, systolic, diastolic, and mean BP, HR, SV, and CO increased significantly (P, 0.001, P, 0.001, P, 0.001, P ¼ 0.001, P, 0.001, and P, 0.001, respectively), whereas TPR did not change significantly. At the fifth minute of recovery, all the variables showed a further significant increase with the exception of HR and TPR, which did not change significantly. After 15 min of recovery, the values of all the variables returned to baseline (pre-tilt) values. Discussion Main findings The main finding of the present study is that the fall in BP during both prodromal symptoms and loss of consciousness appears to be due to the marked reduction in SV and CO, as the calculated TPR showed a slight but significant increase at the beginning of prodrome. Similarly, the increase in BP during the recovery phase is associated with a marked increase in SV and CO, without significant changes in calculated TPR. These data suggest that the fall in BP during orthostatic syncope and the subsequent rise after tilting back to the horizontal are mainly dependent on the venous system. Only in one young patient (5%) hypotension appeared secondary to a fall in TPR, as CO increased during loss of consciousness. The fall in CO before loss of consciousness is partly secondary to the reduction in HR, and the rise in CO at the beginning of recovery is partly secondary to the increase in HR. However, it should be pointed out that before loss of consciousness SV decreases in spite of the decrease in HR, and at the beginning of recovery SV increases in spite of the increase in HR. That seems to strengthen the role of the venous return in the genesis of hypotension in VVS patients. In humans, orthostatic stress normally evokes compensatory vasoconstriction; when this compensatory mechanism fails within the venous system, venoconstriction is inadequate, leading to reduced venous return to the heart and, ultimately, to a fall in BP. It is well known that VVS is reversed more rapidly by laying the patient down and raising the legs but, to our knowledge, the haemodynamics of the recovery phase has not been thoroughly investigated and, consequently, the haemodynamic behaviour of this phase has not been sufficiently taken into account in the analysis of the determinants of hypotension. Some authors 23,32 have reported, even during invasive investigation, 32 a decrease in TPR just before loss of consciousness during TT; this suggests a reduction of the arterial tone and therefore a role of the arterial system in the genesis of hypotension. On the contrary, we have observed a slight but significant increase in calculated TPR at the
6 844 G. Fucà et al. beginning of prodromal symptoms (Figures 2 and 5). There is not a clear explanation for the different behaviour of TPR observed by us and these authors; however, examination of the behaviour of TPR in these studies 23,32 reveals that it does not fall below the pre-tilt values at any time during the entire TT, not even during loss of consciousness. This suggests that a reduction in arterial tone is not the main determinant of the hypotension that leads to loss of consciousness. The increase in calculated TPR we observed just before loss of consciousness could be an attempt of arterial system to counteract reduction in SV that follows a decrease in venous return; however, the arterial system appears unable to make the appropriate compensatory vasoconstriction. In this regard, an increase in calculated TPR just before tilt-induced syncope has recently been reported after nitroglycerine administration. 33 These results suggest that the withdrawal of sympathetic tone, which appears responsible for the vascular changes preceding loss of consciousness, as shown by Wallin et al., 6 mainly affects the venous and, to a lesser extent, the arterial system. Previous studies Impaired venoconstriction has been suggested as an underlying cause of the fall in BP A greater increase in calf and in splanchnic blood volume has been observed during TT in patients with a positive response than in control subjects 13,19 as an expression of reduced venoconstrictive response. During physical exercise, splenic volume is reported to decrease to a lesser degree in patients with VVS than in control subjects, 16 and, during mental stress, a lower forearm venoconstrictive response has been observed in VVS patients than in controls. 15 During the first and intermediate phases of TT, the reduction or the rate of reduction in SV or end-diastolic volume has been seen to be greater in patients with positive TT than in controls. 11,12,14,17,18 In the studies by de Jong-de Vos van Steenwijk et al. 21 and Novak et al., 23 a decrease in SV and CO was not observed in patients with positive TT before loss of consciousness, and hypotension appeared secondary to a fall in calculated TPR. However, the former study investigated paediatric subjects without a history of spontaneous syncope, who might show a different haemodynamic behaviour. In the latter study, SV and CO were measured by using thoracic impedance, which Marik et al. 34 defined as unreliable to measure these variables. The reduction in SV that we and other authors 11,17,32,35 observed before loss of consciousness might be related not only to a reduced venous return but also to an impairment of myocardial contractility. In this regard, the literature offers rather contrasting data. Some authors 36,37 have reported a fall of dp/dt max or peak endocardial acceleration just before loss of consciousness; others 38,39 have not observed this fall. In most studies, 12,32,40 left ventricular ejection fraction or fractional shortening increased before tilt-induced syncope; in others, 14,17 a decrease or a nonsignificant change has been reported. On the basis of the present knowledge, there is no evidence for left ventricular systolic dysfunction before loss of consciousness. Some authors 20,22,24,25 have reported a smaller increase in calculated TPR during the initial phase of TT or during lower body negative pressure in patients with positive TT than in control subjects. For this reason, they suggest a role of the arterial system in the genesis of the fall in BP. However, these results do not enable us to understand whether the impaired arterial vasoconstriction is the main determinant of hypotension. Study limitations Tilt-induced syncope may not be the physiological equivalent of VVS, which can be triggered by a variety of stimuli other than orthostatic stress. 41 After calibration, the tracking of changes in SV and CO with modelflow vs. thermodilution-based estimate changes compared within 5 + 2% during prolonged TT. 42 However, if absolute values are not required, the modelflow method gives reliable trend data, and changes in these haemodynamic variables can be tracked from an arterial pressure waveform. A complex mixture of inter-related factors (i.e. endocrine, physical, interactions between pre-load and afterload, etc.) can affect CO and, at present, distinguishing one from another is not possible, which can undermine the reliability of the conclusions. Total peripheral resistance is always calculated as the quotient of mean BP and CO. We cannot be sure that this quotient, measured by means of any invasive or non-invasive method, is a true expression of the arterial tone. Moreover, even if the arterial tone is much higher than the venous tone, the estimated TPR does not allow us to differentiate the venous contribution from that of the arterial system. It must also be pointed out that in the clinical setting it is not possible to dissociate completely pre-load and afterload as both condition SV. The beginning of prodromal symptoms we recorded could not be very precise, above all in old patients. Conclusion The results of the present study add further support to the notion that VVS is mainly related to an impaired venoconstrictive response, leading to reduced venous return to the heart. This is suggested by the haemodynamic behaviour before tilt-induced syncope and, above all, by the behaviour during the recovery phase. The arterial system appears to be the main determinant of the fall in BP in very few patients, and in the others this system is unable to make the appropriate compensatory changes. Our results, together with those obtained in paediatric subjects, 21 suggest that the behaviour of calculated TPR just before loss of consciousness could be different in young and old subjects; however, that requires further investigation. References 1. Almquist A, Goldenberg IF, Milstein S et al. Provocation of bradycardia and hypotension by isoproterenol and upright posture in patients with unexplained syncope. N Engl J Med 1989;320: Fitzpatrick A, Sutton R. Tiltings towards a diagnosis in recurrent unexplained syncope. Lancet 1989;1: Waxman MB, Yao L, Cameron DA, Wald RW, Roseman J. Isoproterenol induction of vasodepressor-type reaction in vasodepressor-prone persons. Am J Cardiol 1989;63: Raviele A, Gasparini G, Pede FD, Delise P, Bonso A, Piccolo E. Usefulness of head-up tilt test in evaluating patients with syncope of unknown origin and negative electrophysiologic study. Am J Cardiol 1990;65:
7 Venous system: the main determinant of hypotension Grubb BP, Kosinski D. Tilt table testing: concepts and limitations. Pacing Clin Electrophysiol 1997;20: Wallin BG, Sundlöf G. Sympathetic outflow to muscles during vasovagal syncope. J Auton Nerv Syst 1982;6: Van Lieshout JJ, Wieling W, Karemaker JM, Eckberg DL. The vasovagal response. Clin Sci (Lond) 1991;81: Smith M, Ellenbogen KA, Eckberg DL. Sympathoinhibition and hypotension in carotid sinus hypersensitivity. Clin Auton Res 1992;2: Dietz NM, Halliwill JR, Spielmann JM et al. Sympathetic withdrawal and forearm vasodilation during vasovagal syncope. J Appl Physiol 1997;82: Mosqueda-Garcia R, Furlan R, Fernandez-Violante R et al. Sympathetic and baroreceptor reflex function in neurally mediated syncope evoked by tilt. J Clin Invest 1997;99: Jardine DL, Melton IC, Crozier IG et al. Decrease in cardiac output and muscle sympathetic activity during vasovagal syncope. Am J Physiol Heart Circ Physiol 2002;282:H Shalev Y, Rami G, Tchou PJ et al. Echocardiographic demonstration of decreased left ventricular dimensions and vigorous myocardial contraction during syncope induced by head-up tilt. J Am Coll Cardiol 1991;18: Hargreaves AD, Muir AL. Lack of variation in venous tone potentiates vasovagal syncope. Br Heart J 1992;67: Mizumaki K, Fujiki A, Tani M, Shimono M, Hayashi H, Inoue H. Left ventricular dimensions and autonomic balance during head-up tilt differ between patients with isoproterenol-dependent and isoproterenolindependent neurally mediated syncope. J Am Coll Cardiol 1995;26: Manyari DE, Rose S, Tyberg JV, Sheldon RS. Abnormal reflex venous function in patients with vasovagal syncope. J Am Coll Cardiol 1996;27: Thompson HL, Atherton JJ, Khafagi FA, Frenneaux MP. Failure of reflex venoconstriction during exercise in patients with vasovagal syncope. Circulation 1996;93: Yamanouchi Y, Jaalouk S, Shehadeh AA, Jaeger F, Goren H, Fouad-Tarazi FM. Changes in left ventricular volume during head-up tilt in patients with vasovagal syncope: an echocardiographic study. Am Heart J 1996;131: Liu JE, Hahn RT, Stein KM et al. Left ventricular geometry and function preceding neurally mediated syncope. Circulation 2000;101: Steward JM, McLeod KJ, Sanyal S, Herzberg G, Montgomery LD. Relation of postural vasovagal syncope to splanchnic hypervolemia in adolescents. Circulation 2004;110: Sneddon JF, Counihan PJ, Bashir Y, Haywood GA, Ward DE, Camm AJ. Impaired immediate vasoconstrictor responses in patients with recurrent neurally mediated syncope. Am J Cardiol 1993;71: de Jong-de Vos van Steenwijk CCE, Wieling W, Johannes JM, Harms MP, Kuis W, Wesseling KH. Incidence and hemodynamic characteristics of near-fainting in healthy 6- to 16-year old subjects. J Am Coll Cardiol 1995;25: Thomson HL, Lele SS, Atherton JJ, Wright KN, Stafford W, Frenneaux MP. Abnormal forearm vascular responses during dynamic leg exercise in patients with vasovagal syncope. Circulation 1995;92: Novak V, Honos G, Shondorf R. Is the heart empty at syncope? J Auton Nerv Syst 1996;60: Thomson HL, Wright K, Frenneaux M. Baroreflex sensitivity in patients with vasovagal syncope. Circulation 1997;95: Shen WK, Low PA, Rea RF, Lohse CM, Hodge DD, Hammil SC. Distinct hemodynamic profiles in patients with vasovagal syncope: a heterogeneous population. J Am Coll Cardiol 2000;35: Brignole M, Alboni P, Benditt DG et al. Guidelines on management (diagnosis and treatment) of syncope update Europace 2004; 6: Van Lieshout JJ, Wieling W, Karemaker JM, Secher NH. Syncope, cerebral perfusion and oxygenation. J Appl Physiol 2003;94: Wesseling KH, Settels JJ, van der Hoeven GMA, Nijboer JA, Butyn MWT, Dorlas JC. Effects of peripheral vasocostriction on the measurement of blood pressure in a finger. Cardiovasc Res 1985;19: Wesseling KH, Jansen JRC, Settels JJ et al. Computation of aortic flow from pressure in humans using a nonlinear, three-element model. J Appl Physiol 1993;74: Alboni P, Dinelli M, Gruppillo P et al. Haemodynamic changes early in prodromal symptoms of vasovagal syncope. Europace 2002;4: Brignole M, Menozzi C, Del Rosso A et al. New classification of haemodynamics of vasovagal syncope: beyond the VASIS classification. Analysis of pre-syncopal phase of the tilt test without and with nitroglycerin challenge. Europace 2000;2: Fitzpatrick A, Williams T, Ahmed R, Lightman S, Bloom SR, Sutton R. Echocardiographic and endocrine changes during vasovagal syncope induced by prolonged head-up tilt. Eur J Card Pacing Electrophysiol 1992;2: Gisolf J, Westerhof BE, van Dijk N, Wesseling KH, Wieling W, Karemaker JM. Sublingual nitroglycerin used in routine tilt testing provokes a cardiac output-mediated vasovagal response. J Am Coll Cardiol 2004;44: Marik PE, Pendelton JE, Smith R. A comparison of hemodynamic parameters from transthoracic electrical bioimpedance with those parameters obtained by thermodilution and angiography. Crit Care Med 1997;25: Bergenwald L, Freyschuss U, Sjöstrand T. The mechanism of orthostatic and hemorrhagic fainting. Scand J Clin Lab Invest 1977;37: Petersen MEV, Wialliams TR, Erickson M, Sutton R. Right ventricular pressure, dp/dt, and preejection interval during tilt induced vasovagal syncope. Pacing Clin Electrophysiol 1997;20: Deharo JC, Peyre JP, Chalvidan T et al. Continuous monitoring of an endocardial index of myocardial contractility during head-up tilt test. Am Heart J 2000;139: Brignole M, Menozzi C, Corbucci G, Garberoglio B, Plicchi G. Detecting incipient vasovagal syncope: intraventricular acceleration. Pacing Clin Electrophysiol 1997;20: Mangin L, Kobeissi A, Lelouche D et al. Simultaneous analysis of heart rate variability and myocardial contractility during head-up tilt in patients with vasovagal syncope. J Cardiovasc Electrophysiol 2001;12: Hosaka H, Takase B, Kitumara K et al. Assessment of left ventricular volume by an ambulatory monitoring system during head-up tilt in patients with unexplained syncope: relation to autonomic activity assessed by heart rate variability. J Nucl Cardiol 2001;8: Benditt DG. Neurally mediated syncopal syndromes: pathophysiological concepts and clinical evaluation. Pacing Clin Electrophysiol 1997;20: Harms MPM, Wesseling KH, Pott F, Jenstrup M, Van Goudoever J, Secher NH, Van Lieshout JJ. Continuous stroke volume arterial pressure in humans under orthostatic stress. Clin Sci (Lond) 1999;97:
Orthostatic hypotension: a new classification system
Europace (2007) 9, 937 941 doi:10.1093/europace/eum177 Orthostatic hypotension: a new classification system B.M.T. Deegan 1,2 *, M. O Connor 3, T. Donnelly 3, S. Carew 3, A. Costelloe 3, T. Sheehy 3, G.
More informationUtility of a Single-Stage Isoproterenol Tilt Table Test in Adults A Randomized Comparison With Passive Head-Up Tilt
Journal of the American College of Cardiology Vol. 33, No. 4, 1999 1999 by the American College of Cardiology ISSN 0735-1097/99/$20.00 Published by Elsevier Science Inc. PII S0735-1097(98)00658-5 Utility
More informationReduced baroreflex sensitivity in patients with vasovagal syncope
DOI: 10.4149/BLL_2015_113 CLINICAL STUDY Reduced baroreflex sensitivity in patients with vasovagal syncope Mitro P, Simurda M, Evin L, Murin P, Muller E Cardiology Clinic, Safarik University and VUSCH
More informationOriginal Article Usefulness of Tilt Testing in Children with Syncope: A Survey of Pediatric Electrophysiologists
www.ipej.org 242 Original Article Usefulness of Tilt Testing in Children with Syncope: A Survey of Pediatric Electrophysiologists Anjan S. Batra, MD 1 and Seshadri Balaji, MBBS, MRCP (UK), PhD 2. 1 University
More informationNeurocardiogenic syncope
Neurocardiogenic syncope Syncope Definition Collapse,Blackout A sudden, transient loss of consciousness and postural tone, with spontaneous recovery Very common Syncope Prevalence All age groups (particularly
More informationIntroduction. * Corresponding author. Tel: þ ; fax: þ address:
Europace (2007) 9, 305 311 doi:10.1093/europace/eum017 Analysis of rhythm variation during spontaneous cardioinhibitory neurally-mediated syncope. Implications for RDR pacing optimization: an ISSUE 2 substudy
More informationFalse Positive Head-up Tilt: Hemodynamic and Neurohumoral Profile
Journal of the American College of Cardiology Vol. 35, No. 1, 2000 1999 by the American College of Cardiology ISSN 0735-1097/00/$20.00 Published by Elsevier Science Inc. PII S0735-1097(99)00500-8 False
More informationIncidence, Clinical Presentation. and Outcome in Patients with Long. Asystole Induced by Head-up Tilt Test
2005 16 134-138 Incidence, Clinical Presentation and Outcome in Patients with Long Asystole Induced by Head-up Tilt Test Ming-Ting Chou, Chen-Chuan Cheng, Wen-Shiann Wu, and Tseui-Yuen Huang Division of
More informationKey Words: Head-up tilt test, Neurally mediated syncope, Unexplained syncope
203 Original Article Randomized Prospective Comparison of Two Protocols for Head-up Tilt Testing in Patients with Normal Heart and Recurrent Unexplained Syncope Mohammad Alasti, MD 1, Mohammad Hosein Nikoo,
More informationIl massaggio del seno carotideo Roberto Maggi Centro Aritmologico e Syncope Unit Lavagna, Italia
Il massaggio del seno carotideo Roberto Maggi Centro Aritmologico e Syncope Unit Lavagna, Italia Tigullio Cardiologia, 7 aprile 2016 Carotid sinus hypersensitivity Vagus nerve Glossopharyngeal nerve Carotid
More informationFront-loaded head-up tilt table testing: validation of a rapid first line nitrate-provoked tilt protocol for the diagnosis of vasovagal syncope
Age and Ageing 2008; 37: 411 415 doi:10.1093/ageing/afn098 The Author 2008. Published by Oxford University Press on behalf of the British Geriatrics Society. All rights reserved. For Permissions, please
More informationTilt Table Testing. Dr. Prateek Suri
Tilt Table Testing Dr. Prateek Suri Background Syncope is very commonly seen in the population Among the various causes of syncope vasovagal syncope is the most common cause There is an absence of a gold
More informationEfficacy of tilt training in the treatment of neurally mediated syncope. A randomized study
Europace (2004) 6, 199e204 Efficacy of tilt training in the treatment of neurally mediated syncope. A randomized study Giovanni Foglia-Manzillo a, ), Franco Giada b, Germano Gaggioli c, Angelo Bartoletti
More informationThe relationship between carotid sinus hypersensitivity, orthostatic hypotension, and vasovagal syncope: a case control study
Europace (2008) 10, 1400 1405 doi:10.1093/europace/eun278 The relationship between carotid sinus hypersensitivity, orthostatic hypotension, and vasovagal syncope: a case control study Maw Pin Tan 1,2,
More informationThe relationship between carotid sinus hypersensitivity, orthostatic hypotension, and vasovagal syncope: a case control study
Europace (2008) 10, 1400 1405 doi:10.1093/europace/eun278 The relationship between carotid sinus hypersensitivity, orthostatic hypotension, and vasovagal syncope: a case control study Maw Pin Tan 1,2,
More informationOBJECTIVES BACKGROUND METHODS
Journal of the American College of Cardiology Vol. 34, No. 5, 1999 1999 by the American College of Cardiology ISSN 0735-1097/99/$20.00 Published by Elsevier Science Inc. PII S0735-1097(99)00365-4 Diagnostic
More informationThe effect of atropine in vasovagal syncope induced by head-up tilt testing
European Heart Journal (1999) 20, 1745 1751 Article No. euhj.1999.1697, available online at http://www.idealibrary.com on The effect of atropine in vasovagal syncope induced by head-up tilt testing M.
More informationIs vasovagal syncope a disease?
Europace (2007) 9, 83 87 doi:10.1093/europace/eul179 OPINION Is vasovagal syncope a disease? Paolo Alboni 1 *, Michele Brignole 2, and Ettore C. degli Uberti 3 1 Division of Cardiology and Arrhythmologic
More informationLa sincope vasovagale come difesa
La sincope vasovagale come difesa Paolo Alboni www.gimsi.it Sezione di Cardiologia e «Syncope Unit» Ospedale Privato Quisisana Ferrara Vasovagal reflex Vasovagal syncope Vasovagal reflex Afferent part
More informationEnhanced Reflex Response to Baroreceptor Deactivation in Subjects With Tilt-Induced Syncope
Journal of the American College of Cardiology Vol. 41, No. 7, 2003 2003 by the American College of Cardiology Foundation ISSN 0735-1097/03/$30.00 Published by Elsevier Science Inc. doi:10.1016/s0735-1097(03)00050-0
More informationManagement of syncope in 2014 Role of tilt test
Gdansk BEATA Symposium October 10-11, 2014 Management of syncope in 2014 Role of tilt test Antonio Raviele, MD, FESC, FHRS ALFA Alliance to Fight Atrial fibrillation, Mestre Venice, Italy Protocols /
More informationResponses to Changes in Posture QUESTIONS. Case PHYSIOLOGY CASES AND PROBLEMS
64 PHYSIOLOGY CASES AND PROBLEMS Case 12 Responses to Changes in Posture Joslin Chambers is a 27-year-old assistant manager at a discount department store. One morning, she awakened from a deep sleep and
More informationHemodynamic effects of leg crossing and skeletal muscle tensing during free standing in patients with vasovagal syncope
J Appl Physiol 98: 584 590, 2005. First published October 8, 2004; doi:10.1152/japplphysiol.00738.2004. Hemodynamic effects of leg crossing and skeletal muscle tensing during free standing in patients
More informationLONG-TERM FOLLOW-UP OF DDDR CLOSED-LOOP PACING FOR RECURRENT VASO-VAGAL SYNCOPE
LONG-TERM FOLLOW-UP OF DDDR CLOSED-LOOP PACING FOR RECURRENT VASO-VAGAL SYNCOPE M. Bortnik, G. Dell'era, E. Occhetta, L. Plebani, P. Marino University of Eastern Piedmont, Department of Cardiology, Novara,
More informationNote: At the end of the instructions, you will find a table which must be filled in to complete the exercise.
Autonomic Nervous System Theoretical foundations and instructions for conducting practical exercises carried out during the course List of practical exercises 1. Deep (controlled) breath test 2. Cold pressor
More informationResearch Article Recurrent Syncope in Patients with Carotid Sinus Hypersensitivity
International Scholarly Research Network ISRN Cardiology Volume 2012, Article ID 216206, 5 pages doi:10.5402/2012/216206 Research Article Recurrent Syncope in Patients with Carotid Sinus Hypersensitivity
More informationSyncope Guidelines Update. Bernard Harbieh, FHRS AUBMC-KMC Beirut-Lebanon
Syncope Guidelines Update Bernard Harbieh, FHRS AUBMC-KMC Beirut-Lebanon New Syncope Guidelines Increase the volume of information on diagnosis and management Incorporation of emergency specialists, neurologists,
More informationUniversity of Groningen
University of Groningen Initial orthostatic hypotension in teenagers and young adults van Wijnen, Veera; Harms, Mark; Go-Schon, I. K.; Westerhof, B. E.; Krediet, C. T. P.; Stewart, J.; Wieling, W. Published
More informationTilt Table Testing MM /01/2015. HMO; PPO; QUEST Integration 09/22/2017 Section: Medicine Place(s) of Service: Office, Outpatient
Tilt Table Testing Policy Number: Original Effective Date: MM.02.024 01/01/2015 Line(s) of Business: Current Effective Date: HMO; PPO; QUEST Integration 09/22/2017 Section: Medicine Place(s) of Service:
More information13/09/2018. The ISSUE Studies. International (Italy & Spain) Study of Syncope of Uncertain Etiology. ISSUE study Pre-defined inclusion cathegories
The Studies Jean-Claude Deharo Aix-Marseille Université, France In Cardiac Electrophysiology Methods and Models Editors: Daniel C. Sigg, Paul A. Iaizzo, Yong-Fu Xiao, Bin He Springer 2010 study Pre-defined
More informationValutazione iniziale e stratificazione del rischio
Valutazione iniziale e stratificazione del rischio Paolo Alboni Sezione di Cardiologia Ospedale Privato Quisisana Ferrara DEFINITION OF SYNCOPE Syncope is a transient loss of consciousness due to global
More informationInadequate sympathovagal balance in response to orthostatism in patients with unexplained syncope and a positive head up tilt test
312 Department of Cardiac Pacing and Electrophysiology, Service de Cardiologie A, Hôpital Cardiologique-CHU, Boulevard du Pr J Leclercq, 59037 Lille Cedex, France C Kouakam D Lacroix N Zghal D Klug P Le
More informationDECLARATION OF CONFLICT OF INTEREST
DECLARATION OF CONFLICT OF INTEREST The Management of Syncope remains a challenge: Clues from the History Richard Sutton, DSc Emeritus Professor of Cardiology Imperial College, St Mary s Hospital, London,
More informationDiagnostic and therapeutic management of the patient with syncope M. Brignole Arrhythmologic Centre and Syncope Unit Lavagna, Italy
Diagnostic and therapeutic management of the patient with syncope M. Brignole Arrhythmologic Centre and Syncope Unit Lavagna, Italy Eur Heart J. 2009 Nov;30(21):2631-71 Available on www.escardio.org/guidelines
More informationHeart Rate Variability Analysis Before and After Pacemaker Implantation in Neuromediated Syncopal Patients
148 April 2001 Heart Rate Variability Analysis Before and After Pacemaker Implantation in Neuromediated Syncopal Patients F. ZOLEZZI, C. ORVIENI, R. NEGRO, C.A. MAZZINI Division of Cardiology, Ospedale
More informationEffectiveness of Physical Counterpressure Maneuvers in Preventing Vasovagal Syncope The Physical Counterpressure Manoeuvres Trial (PC-Trial)
Journal of the American College of Cardiology Vol. 48, No. 8, 2006 2006 by the American College of Cardiology Foundation ISSN 0735-1097/06/$32.00 Published by Elsevier Inc. doi:10.1016/j.jacc.2006.06.059
More informationSyncope: Evaluation of the Weak and Dizzy
Syncope: Evaluation of the Weak and Dizzy William M. Miles, MD, FACC, FHRS Professor of Medicine Silverstein Chair for Cardiovascular Education University of Florida College of Medicine Disclosures Medtronic,
More informationRepeated tilt testing in patients with tilt-positive neurally mediated syncope
Europace (25) 7, 628e633 Repeated tilt testing in patients with tilt-positive neurally mediated syncope Hugo Ector a, *, Rik Willems a, Hein Heidbüchel a, Tony Reybrouck b,c a Department of Cardiology,
More informationSyncope Guidelines: What s New?
Syncope Guidelines: What s New? Dr. Samuel Asirvatham Professor of Medicine and Pediatrics Mayo Clinic College of Medicine Medical Director, Electrophysiology Laboratory Program Director, EP Fellowship
More informationSyncope: Evaluation of the Weak and Dizzy
Syncope: Evaluation of the Weak and Dizzy William M. Miles, MD, FACC, FHRS Professor of Medicine Silverstein Chair for Cardiovascular Education University of Florida College of Medicine Disclosures Medtronic,
More informationCardiac Output MCQ. Professor of Cardiovascular Physiology. Cairo University 2007
Cardiac Output MCQ Abdel Moniem Ibrahim Ahmed, MD Professor of Cardiovascular Physiology Cairo University 2007 90- Guided by Ohm's law when : a- Cardiac output = 5.6 L/min. b- Systolic and diastolic BP
More informationClinical Case 1 A patient with a syncope Panos E. Vardas President Elect of the ESC, Prof of Cardiology, University Hospital of Crete
Clinical Case 1 A patient with a syncope Panos E. Vardas President Elect of the ESC, Prof. of Cardiology, University Hospital of Crete Case presentation A 64-year-old male smoker, with arterial hypertension
More informationI ngestion of water increases seated blood pressure (BP) in
1737 PAPER The effects of water ingestion on orthostatic hypotension in two groups of chronic autonomic failure: multiple system atrophy and pure autonomic failure T M Young, C J Mathias... See end of
More informationJune 8, 2018, London UK TREATMENT OF VASOVAGAL SYNCOPE
June 8, 2018, London UK TREATMENT OF VASOVAGAL SYNCOPE Where to go for help Syncope: HRS Definition Syncope is defined as: a transient loss of consciousness, associated with an inability to maintain postural
More informationC. T. Paul Krediet, Ingeborg K. Go-Schön, Yu-Sok Kim, Mark Linzer, Johannes J. Van Lieshout, Wouter Wieling, C. T. Paul Krediet
Management of initial orthostatic hypotension: lower body muscle tensing attenuates the transient arterial blood pressure decrease upon standing from squatting C. T. Paul Krediet, Ingeborg K. Go-Schön,
More informationVeins. VENOUS RETURN = PRELOAD = End Diastolic Volume= Blood returning to heart per cardiac cycle (EDV) or per minute (Venous Return)
Veins Venous system transports blood back to heart (VENOUS RETURN) Capillaries drain into venules Venules converge to form small veins that exit organs Smaller veins merge to form larger vessels Veins
More informationProlonged Asystole during Head-Up Tilt Test in a Patient with Malignant Neurocardiogenic Syncope
Case Report Prolonged Asystole during Head-Up Tilt Test in a Patient with Malignant Neurocardiogenic Syncope Takashi Tokano MD 1, Yuji Nakazato MD 2, Akitoshi Sasaki MD 3, Gaku Sekita MD 3, Masayuki Yasuda
More informationCentral haemodynamics during spontaneous angina pectoris
British Heart Journal, I974, 36, I0-I09I Central haemodynamics during spontaneous angina pectoris From the Department of Clinical Physiology, Malmo General Hospital, S-214 OI Malmo, Sweden. Central pressures
More informationDeath after Syncope: Can we predict it? Daniel Zamarripa, MD Senior Medical Director December 2013
Death after Syncope: Can we predict it? Daniel Zamarripa, MD Senior Medical Director December 2013 Death after Syncope: Can we predict it? Those who suffer from frequent and severe fainting often die suddenly
More informationCerebral and cardiovascular dynamics in response to orthostatic stress Harms, M.P.M.
UvA-DARE (Digital Academic Repository) Cerebral and cardiovascular dynamics in response to orthostatic stress Harms, M.P.M. Link to publication Citation for published version (APA): Harms, M. P. M. (2008).
More informationCan prodromal symptoms predict recurrence of vasovagal syncope?
ORIGINAL ARTICLE Cardiology Journal 2008, Vol. 15, No. 5, pp. 446 450 Copyright 2008 Via Medica ISSN 1897 5593 Can prodromal symptoms predict recurrence of vasovagal syncope? Amir Farjam Fazelifar 1, Hosein
More information2018 ESC Guidelines for the diagnosis and management of syncope
2018 ESC Guidelines for the diagnosis and management of syncope Michele Brignole (Chairperson) (Italy); Angel Moya (Co-chairperson) (Spain); Jean-Claude Deharo (France); Frederik de Lange (The Netherlands);
More informationClinical features of adenosine sensitive syncope and tilt induced vasovagal syncope
24 Arrhythmologic Centre, Ospedali Riuniti, Lavagna, Italy M Brignole G Gaggioli S Costa A Bartoletti Arrhythmologic Centre, Ospedale S Maria Nuova, Reggio Emilia, Italy C Menozzi N Bottoni G Lolli Department
More informationDistinguishing Cardiac from Non- Cardiac Syncope
10 th Annual International SADS Foundation Conference Toronto Distinguishing Cardiac from Non- Cardiac Syncope Shubhayan Sanatani, MD, FRCPC Head, Division of Cardiology, BC Children s Hospital Director,
More informationRapid Access Clinics for Transient Loss of Consciousness
Rapid Access Clinics for Transient Loss of Consciousness Michael Gammage Department of Cardiovascular Medicine University of Birmingham and University Hospital Birmingham NHS Foundation Trust Those who
More informationTilt-table testing of patients with pacemaker and recurrent syncope Nielsen, Christian E. Haarmark; Kanters, Jørgen K.
university of copenhagen Tilt-table testing of patients with pacemaker and recurrent syncope Nielsen, Christian E. Haarmark; Kanters, Jørgen K.; Mehlsen, Jesper Published in: Indian Pacing and Electrophysiology
More informationOn the Track of Syncope induced by Orthostatic Stress - Feedback Mechanisms Regulating the Cardiovascular System
Proceedings of the 7th IFAC Symposium on Modelling and Control in Biomedical Systems On the Track of Syncope induced by Orthostatic Stress - Feedback Mechanisms Regulating the Cardiovascular System Ottesen
More information(D) (E) (F) 6. The extrasystolic beat would produce (A) increased pulse pressure because contractility. is increased. increased
Review Test 1. A 53-year-old woman is found, by arteriography, to have 5% narrowing of her left renal artery. What is the expected change in blood flow through the stenotic artery? Decrease to 1 2 Decrease
More informationHypotensive susceptibility and antihypertensive drugs Diana Solari Santa Margherita Ligure, 7 aprile 2016
Hypotensive susceptibility and antihypertensive drugs Diana Solari Santa Margherita Ligure, 7 aprile 2016 Arrhythmologic Center, Department of Cardiology, Lavagna SYNCOPE AND ANTIHYPERTENSIVE DRUGS Many
More informationSYNCOPE. Sanjay P. Singh, MD Chairman & Professor, Department of Neurology. Syncope
SYNCOPE Sanjay P. Singh, MD Chairman & Professor, Department of Neurology. Syncope Syncope is a clinical syndrome characterized by transient loss of consciousness (TLOC) and postural tone that is most
More informationSyncope and TLOC overview
PART 1 Syncope and TLOC overview 1 2 CHAPTER 1 Definition and classification of syncope and transient loss of consciousness Jean-Jacques Blanc Syncope is a common complaint responsible for up to 1% of
More informationREGULATION OF CARDIOVASCULAR FUNCTIONS DURING ACUTE BLOOD LOSS
Indian J Physiol Pharmacol 2005; 49 (2) : 213 219 REGULATION OF CARDIOVASCULAR FUNCTIONS DURING ACUTE BLOOD LOSS RAJINDER K. GUPTA* AND MOHAMMAD FAHIM Department of Physiology, Vallabhbhai Patel Chest
More informationMalignant vasovagal syncope: a randomised trial of metoprolol and clonidine
268 Institute of Cardiology, Policlinico S Orsola, University of Bologna, Italy M Biffi G Boriani P Sabbatani G Bronzetti L Frabetti R Zannoli A Branzi B Magnani Correspondence to: Dr M Biffi, Institute
More informationORIGINAL ARTICLE. Tilt training and pacing: a report on 9 patients with neurally mediated syncope
Acta Cardiol 2010; 65(1): 3-7 doi: 10.2143/AC.65.1.2045882 3 ORIGINAL ARTICLE Tilt training and pacing: a report on 9 patients with neurally mediated syncope Tony REYBROUCK, PhD; Hein HEIDBÜCHEL, MD, PhD;
More informationOver the past decade, tilt testing has become a widely
Induction of Neurally Mediated Syncope With Adenosine Suneet Mittal, MD; Kenneth M. Stein, MD; Steven M. Markowitz, MD; David J. Slotwiner, MD; Sameer Rohatgi, MD; Bruce B. Lerman, MD Background Tilt testing
More informationGender Difference in Patients with Recurrent Neurally Mediated Syncope
Original Article DOI 10.3349/ymj.2010.51.4.499 pissn: 0513-5796, eissn: 1976-2437 Yonsei Med J 51(4):499-503, 2010 Gender Difference in Patients with Recurrent Neurally Mediated Syncope Jungwae Park, 1
More informationCerebral and cardiovascular dynamics in response to orthostatic stress Harms, M.P.M.
UvA-DARE (Digital Academic Repository) Cerebral and cardiovascular dynamics in response to orthostatic stress Harms, M.P.M. Link to publication Citation for published version (APA): Harms, M. P. M. (2008).
More informationLee Chee Wan. Senior Consultant Pacing and Cardiac Electrophysiology. GP Symposium 2 nd April 2016
Lee Chee Wan Senior Consultant Pacing and Cardiac Electrophysiology GP Symposium 2 nd April 2016 Objectives Definition of syncope Common causes of syncope & impacts How to clinically assess patient with
More informationThe normal response to prolonged passive head up tilt testing
Heart 2000;84:509 514 509 Department of Cardiology, Chelsea and Westminster Hospital, 369 Fulham Road, London SW10 9NH, UK MEVPetersen T R Williams C Gordon R Chamberlain-Webber R Sutton Correspondence
More informationClinical Assessment of Cardiovascular and Autonomic Function Using Virtual Instrumentation
Clinical Assessment of Cardiovascular and Autonomic Function Using Virtual Instrumentation Diego Santiago BENITEZ 1,2 1 Colegio Politécnico, Universidad San Francisco de Quito, Quito, Ecuador and Patrick
More informationStepwise Evaluation of Unexplained Syncope in a Large Ambulatory Population
Stepwise Evaluation of Unexplained Syncope in a Large Ambulatory Population JUAN F. IGLESIAS, M.D., DENIS GRAF, M.D., ANDREI FORCLAZ, M.D., JUERG SCHLAEPFER, M.D., MARTIN FROMER, M.D., and ETIENNE PRUVOT,
More informationTriggering Mechanism for Neurally Mediated Syncope Induced by Head-up Tilt Test Role of Catecholamines and Response to Propranolol
Journal of the American College of Cardiology Vol. 33, No. 2, 1999 1999 by the American College of Cardiology ISSN 0735-1097/99/$20.00 Published by Elsevier Science Inc. PII S0735-1097(98)00567-1 Triggering
More informationMedicine Dr. Aso Lecture 9 Syncope and Pre-syncope
Medicine Dr. Aso Lecture 9 Syncope and Pre-syncope SYNCOPE AND PRE-SYNCOPE Syncope:- sudden, transient loss of consciousness, due to reduced cerebral perfusion. The patient is unresponsive with loss of
More informationThe Journal of Physiology
J Physiol 590.8 (2012) pp 1839 1848 1839 Cardiac output and sympathetic vasoconstrictor responses during upright tilt to presyncope in healthy humans Qi Fu 1,2, Bart Verheyden 3,WouterWieling 4 and Benjamin
More informationAn Abnormal Neural Reflex Plays a Role in Causing Syncope in Sinus I3radycardia
1130 JACC Vol. 22. No. 4 (ember 1993;22 :1130-4 An Abnormal Neural Reflex Plays a Role in Causing Syncope in Sinus I3radycardia PAOLO ALBONI, MD, FACC, CARLO MENOZZI, MD,* MICHELE BRIGNOLE, MD,t NELLY
More informationThe randomized, double-blind, Third International Study. Original Article
Original Article Benefit of Pacemaker Therapy in Patients With Presumed Neurally Mediated Syncope and Documented Asystole Is Greater When Tilt Test Is Negative An Analysis From the Third International
More informationPrinciples of Biomedical Systems & Devices. Lecture 8: Cardiovascular Dynamics Dr. Maria Tahamont
Principles of Biomedical Systems & Devices Lecture 8: Cardiovascular Dynamics Dr. Maria Tahamont Review of Cardiac Anatomy Four chambers Two atria-receive blood from the vena cave and pulmonary veins Two
More informationClinical Characteristics of Defecation Syncope Compared With Micturition Syncope
Circulation Journal Official Journal of the Japanese Circulation Society http://www.j-circ.or.jp ORIGINAL ARTICLE Hypertension and Circulatory Control Clinical Characteristics of Defecation Syncope Compared
More informationCardiovascular Responses to Exercise
CARDIOVASCULAR PHYSIOLOGY 69 Case 13 Cardiovascular Responses to Exercise Cassandra Farias is a 34-year-old dietician at an academic medical center. She believes in the importance of a healthy lifestyle
More informationExperimental Physiology
2 Exp Physiol 100.1 (2015) pp 2 11 Research Paper Research Paper Slower lower limb blood pooling in young women with orthostatic intolerance Marcus Lindenberger 1,2 and Toste Länne 1 1 Department of Medical
More informationHeart Pump and Cardiac Cycle. Faisal I. Mohammed, MD, PhD
Heart Pump and Cardiac Cycle Faisal I. Mohammed, MD, PhD 1 Objectives To understand the volume, mechanical, pressure and electrical changes during the cardiac cycle To understand the inter-relationship
More informationSincope e bradicardia sinusale: quale è la terapia appropriata?
Sincope e bradicardia sinusale: quale è la terapia appropriata? Paolo Alboni, Key points: 1 Fisiopatologia della sincope nei pz con BS 2 Diagnosi del tipo of sincope nei pz con BS 3 Trattamento della syncope
More informationChapter 9, Part 2. Cardiocirculatory Adjustments to Exercise
Chapter 9, Part 2 Cardiocirculatory Adjustments to Exercise Electrical Activity of the Heart Contraction of the heart depends on electrical stimulation of the myocardium Impulse is initiated in the right
More informationFrith J, Parry SW. Tilt-table testing: down but not out. Clinical Practice 2014, 11(3),
Frith J, Parry SW. Tilt-table testing: down but not out. Clinical Practice 2014, 11(3), 265-268. Copyright: 2014 Future Medicine Ltd. DOI link to article: http://dx.doi.org/10.2217/cpr.14.21 Date deposited:
More informationImpedance Cardiography (ICG) Method, Technology and Validity
Method, Technology and Validity Hemodynamic Basics Cardiovascular System Cardiac Output (CO) Mean arterial pressure (MAP) Variable resistance (SVR) Aortic valve Left ventricle Elastic arteries / Aorta
More informationFaculty Disclosure. Sanjay P. Singh, MD, FAAN. Dr. Singh has listed an affiliation with: Consultant Sun Pharma Speaker s Bureau Lundbeck, Sunovion
Faculty Disclosure Sanjay P. Singh, MD, FAAN Dr. Singh has listed an affiliation with: Consultant Sun Pharma Speaker s Bureau Lundbeck, Sunovion however, no conflict of interest exists for this conference.
More informationC1: Medical Standards for Safety Critical Workers with Cardiovascular Disorders
C1: Medical Standards for Safety Critical Workers with Cardiovascular Disorders GENERAL ISSUES REGARDING MEDICAL FITNESS-FOR-DUTY 1. These medical standards apply to Union Pacific Railroad (UPRR) employees
More informationChanges in the transthoracic impedance signal predict the outcome of a 70 head-up tilt test
Clinical Science (2003) 104, 119 126 (Printed in Great Britain) 119 Changes in the transthoracic impedance signal predict the outcome of a 70 head-up tilt test Elisabeth BELLARD*, Jacques-Olivier FORTRAT*,
More informationCardiovascular Physiology
Cardiovascular Physiology Introduction The cardiovascular system consists of the heart and two vascular systems, the systemic and pulmonary circulations. The heart pumps blood through two vascular systems
More informationPOSTURAL ORTHOSTATIC TACHYCARDIA SYNDROME (POTS) IT S NOT THAT SIMPLE
POSTURAL ORTHOSTATIC TACHYCARDIA SYNDROME (POTS) IT S NOT THAT SIMPLE POTS Irritable heart syndrome. Soldier s heart. Effort syndrome. Vasoregulatory asthenia. Neurocirculatory asthenia. Anxiety neurosis.
More informationImpedance Cardiography (ICG) Application of ICG for Hypertension Management
Application of ICG for Hypertension Management 1mA @ 100 khz Impedance Cardiography (ICG) Non-invasive Beat-to-beat Hemodynamic Monitoring Diastole Systole Aortic valve is closed No blood flow in the aorta
More informationPositive Result in the Early Passive Phase of the Tilt-table Test: A Predictor of Neurocardiogenic Syncope in Young Men
ORIGINAL ARTICLE korean j intern med 202;27:60-65 pissn 226-3303 eissn 2005-6648 Positive Result in the Early Passive Phase of the Tilt-table Test: A Predictor of Neurocardiogenic Syncope in Young Men
More informationCerebral Blood Flow Velocity Declines Before Arterial Pressure in Patients With Orthostatic Vasovagal Presyncope
Journal of the American College of Cardiology Vol. 39, No. 6, 2002 2002 by the American College of Cardiology Foundation ISSN 0735-1097/02/$22.00 Published by Elsevier Science Inc. PII S0735-1097(02)01719-9
More informationVasovagal syncope in 2016: the current state of the faint
Interventional Cardiology Vasovagal syncope in 2016: the current state of the faint In this article, we will review the challenges in defining syncope and the evolution of its definition over the past
More informationResearch Article Cerebral Blood Flow, Heart Rate, and Blood Pressure Patterns during the Tilt Test in Common Orthostatic Syndromes
Neuroscience Journal Volume 216, Article ID 612734, 2 pages http://dx.doi.org/1.1155/216/612734 Research Article Cerebral Blood Flow, Heart Rate, and Blood Pressure Patterns during the Test in Common Orthostatic
More informationElectrocardiographic characteristics of atrioventricular block induced by tilt testing
Europace (2009) 11, 225 230 doi:10.1093/europace/eun299 CLINICAL RESEARCH Syncope Electrocardiographic characteristics of atrioventricular block induced by tilt testing Dorota Zyśko 1 *, Jacek Gajek 2,
More informationVariable Cerebral Dysfunction During Tilt Induced Vasovagal Syncope
Variable Cerebral Dysfunction During Tilt Induced Vasovagal Syncope FABRIZIO AMMIRATI, FURIO COLIVICCHI, GIANCARLO DI BATTISTA,* FAUSTO FIUME GARELLI,* GLAUDIO PANDOZI, and MASSIMO SANTINI From the *Heart
More informationPathophysiological Basis of Syncope and Neurological Conditions that Mimic Syncope
PROGRESS IN CARDIOVASCULAR DISEASES 55 (2013) 345 356 Available online at www.sciencedirect.com www.onlinepcd.com Pathophysiological Basis of Syncope and Neurological Conditions that Mimic Syncope J. Gert
More informationAPPENDIX D1 - CHARACTERISTICS OF INCLUDED STUDIES
APPENDIX D1 - CHARACTERISTICS OF INCLUDED STUDIES 1 Initial Assessment included studies table... 3 1.1 Initial symptoms for diagnosis review... 3 1.2 Decision rules for diagnosis review... 8 1.3 Initial
More information