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Head-up Tilt Test (head-up + tilt_test)
Selected AbstractsLong-Term Follow-Up of Patients with Syncope Evaluated by Head-Up Tilt TestANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 2 2010Giulia Domenichini M.D. Background: Clinicians may be tempted to consider a positive head-up tilt test (HUTT) an unfavorable prognostic indicator. We investigated whether results of routine HUTT predict long-term recurrence of syncope. Methods: We analyzed syncope recurrence at long-term among 107 patients (mean age 51 ± 20 years) receiving HUTT for diagnostic evaluation of unexplained/suspected neurocardiogenic syncope in our Institute. Results: HUTT was positive in 76 patients (vasodepressive response, n = 58; cardioinhibitory, n = 5; mixed, n = 13). During a median follow-up of 113 months (range, 7,161), 34 (32%) patients experienced recurrence (24 [32%] with positive HUTT during 110 months (7,159); 10 [32%] with negative HUTT during 120 [22,161] months). Actuarial freedom from recurrence at 10 years did not significantly differ for patients with positive/negative test results (after passive/active phases) or with different positive response patterns (vasodepressive, cardioinhibitory, mixed). By contrast, history of >4 syncopes in the 12 months preceding HUTT stratified risk of recurrence, irrespective of HUTT positivity/negativity. At Cox proportional hazards analysis, history of >4 syncopes in the 12 months preceding HUTT was the single independent risk factor for recurrence both in the overall study population (HR, 1.7; 95% CI, 1.07,2.69) and within the subset of patients who tested positive (HR, 1.83; 95% CI, 1.07,3.17). Conclusions: This long-term follow-up study reinforces the concept that a positive HUTT should not be considered an unfavorable prognostic indicator; frequency of recent occurrences may be a more valid predictor. Ann Noninvasive Electrocardiol 2010;15(2):101,106 [source] Aetiologic and clinical characteristics of syncope in Chinese childrenACTA PAEDIATRICA, Issue 10 2007Li Chen Abstract Aim: This study aimed to improve diagnostic efficacy of syncope in children by analyzing the aetiology and clinical characteristics of syncope in Chinese children. Methods: We retrospectively analyzed the causes of syncope and diagnostic workup in 154 consecutive children seen in the Department of Pediatrics, Peking University First Hospital, China, because of a syncope-related event. Results: In all patients with transient loss of consciousness (TLOC), there were 136 (88.31%) patients attributing to syncope, and 18 (11.69%) belonging to nonsyncopal cases. Neurally mediated syncope (NMS) was the most common cause of syncope (99 cases; 64.3%), with cardiac causes ranking second (10 cases; 6.5%). Other nonsyncopal causes included psychiatric problems and neurological and metabolic disorders. In 25 cases (16.2%), the cause was uncertain. Cases of NMS often had clear inducement of syncope and prodromes. Children with cardiac syncope often had a history of cardiac disease, were often younger than those with NMS, and showed exercise-related syncope, syncope spells in any body position or at an early age, or sudden death in family members but no prodromes. Neurological disorder was suspected in cases of TLOC with seizures, TLOC spells in any position, postictal phase of disorientation or abnormal neurological signs. A metabolic cause is suspected with a history of metabolic disease, prolonged anger, or violent vomiting and diarrhoea. Children with psychiatric disorders were adolescent girls, with prolonged TLOC spells, who had more frequent TLOC. Although many tests were used in diagnosis, most were not goal directed. Now, electrocardiography is recommended in almost all children with syncope. Neurological testing, including electroencephalography and computed tomography were rarely helpful unless with evidence of neurological signs and symptoms. Head-up tilt test (HUTT) was most useful in children with recurrent syncope in whom heart disease was not suspected. Conclusion: NMS was the most common cause of syncope. We recommended HUTT as the important basis of the TLOC workup. [source] Effect of deep brain stimulation of the posterior hypothalamic area on the cardiovascular system in chronic cluster headache patientsEUROPEAN JOURNAL OF NEUROLOGY, Issue 9 2007P. Cortelli The objective of this study was to determine the cardiovascular effects of chronic stimulation of the posterior hypothalamic area (PHA) in cluster headache (CH) patients. Systolic and diastolic blood pressure (SBP, DBP), cardiac output, total peripheral resistance (TPR), heart rate (HR) and breathing were monitored at supine rest and during head-up tilt test (HUTT), Valsalva manoeuvre, deep breathing, cold face test and isometric handgrip in eight drug-resistant chronic CH patients who underwent monolateral electrode implantation in the PHA for therapeutic purposes. Autoregressive power spectral analysis (PSA) of HR variability (HRV) was calculated at rest and during HUTT. Each subject was studied before surgery (condition A) and after chronic deep brain stimulation (DBS) of PHA (condition B). Baseline SBP, DBP, HR and cardiovascular reflexes were normal and similar in both conditions. With respect to condition A, DBP, TPR and the LF/HF obtained from the PSA of HRV were significantly (P < 0.05) increased during HUTT in condition B. In conclusion, chronic DBS of the PHA in chronic CH patients is associated with an enhanced sympathoexcitatory drive on the cardiovascular system during HUTT. [source] Predicting Recurrence of Vasovagal Syncope: A Simple Risk Score for the Clinical RoutineJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 4 2009MUHAMMET A. AYDIN M.D. Background: Predictors for recurrence of syncope are lacking in patients with vasovagal syncope. The aim of this study was to identify risk factors for recurrence of syncope and develop a simple prognostic risk score of clinical value. Methods: Two hundred seventy-six patients with a history of vasovagal syncope were prospectively followed for 2 years. Diagnosis of vasovagal syncope was based on clinical history and negative standard work-up. Inclusion in the study was independent from the result of the head-up tilt test, which was performed in all cases. Risk factors for syncope recurrence were evaluated by the Cox proportional hazards regression model and implemented in a risk score, which was validated with the log-rank test and an internal cross-validation. Results: The Cox-regression analysis identified the number of previous syncopal events, history of bronchial asthma, and female gender as predictors for syncope recurrence (all P < 0.05). In contrast, head-up tilt test response had no predictive value (P = 0.881). Developing a risk score, study patients were identified as having high (recurrence rate during 2 years of follow-up: 37.2%), intermediate (24.8%), and low (6.5%) risk for syncope recurrence (receiver operating characteristic [ROC] of score 0.83, P < 0.01; Log-rank test for event-free survival, P < 0.005). Conclusions: In patients with vasovagal syncope, risk of recurrence can be stratified and is predictable based on a simple risk score. [source] Is Home Orthostatic Self-Training Effective in Preventing Neurally Mediated Syncope?PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 5 2007Ph.D., YOUNG KEUN ON M.D. Background:Repeated orthostatic stress may prove to be of benefit in the regulation of neurally mediated syncope. But the role of home orthostatic self-training is not established to prevent symptoms in patients with neurally mediated syncope. We performed a prospective and randomized study to evaluate the effectiveness of repeated home orthostatic self-training in preventing tilt-induced neurally mediated syncope. Methods and Results:Fourty-two consecutive patients (24 males and 18 females, mean age 39 years, 16,68 years) with recurrent neurally mediated syncope were randomized into the tilt training and control groups. The home orthostatic self-training program consisted of daily sessions for 7 days a week for 4 weeks. In order to determine the effects of home orthostatic self-training, we repeated the head-up tilt test in both groups 4 weeks later. Among the tilt-training group, 9 of 16 patients (56%) had a positive response on follow-up head-up tilt test. Among the untreated control group, 9 of 17 patients (53%) had a positive response on follow-up head-up tilt test. In subgroup analyses according to the number of tilt-training sessions or the classified type, we found no differences in the follow-up head-up tilt test responses. Spontaneous syncope or presyncope over mean follow-up of 16.9 months were observed in 42.9% versus 47.1% in the tilt-training and control group, respectively. Conclusions:Home orthostatic self-training was ineffective in reducing the positive response rate of head-up tilt test in patients with recurrent neurally mediated syncope. [source] Myocardial Contractility and Cardiac Filling Measured by Impedance Cardiography in Patients with Nitroglycerine-Induced Vasovagal SyncopePACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 1 2006PETER MITRO Objective: Increased myocardial contractility and inadequate cardiac filling leading to activation of the Bezold-Jarisch reflex were proposed as possible triggering mechanisms of vasovagal syncope (VVS). In the present study noninvasive hemodynamic measurements were performed in order to examine the role of myocardial contractility and cardiac filling in pathogenesis of VVS. Methods: Hemodynamic parameters were measured during head-up tilt test (HUT) by impedance cardiography in 46 patients with unexplained syncope. Myocardial contractility was measured as index of contractility (IC), acceleration index (ACI), and ejection fraction (EF). Afterload was measured as systemic vascular resistance index (SVRI) and preload was expressed as end-diastolic index (EDI). Serial measurements were done 1 minute before HUT, during HUT at 1-minute intervals, and 1 minute after completion of HUT. Results: HUT was positive in 30 patients (10 men, 20 women, mean age 36 ± 16 years) and negative in 16 patients (8 men, 8 women, mean age 31 ± 14 years). No significant differences were observed between HUT(+) and HUT(,) groups in hemodynamic parameters at supine rest and during HUT until the development of syncope. SVRI was lower in HUT(+) than in HUT(,) group at syncope (122.7 + 66.3 vs 185.6 + 51.4 dyn sec cm,5/m2, P = 0.002) and after syncope (117.0 + 61.1 vs 198.0 + 95.7 dyn sec cm,5/m2, P = 0.007). ACI, IC, EF, and EDI did not differ between groups at syncope. After syncope EF was higher in HUT(+) group compared to HUT(,) group (59.2 + 6.1 vs 52.7 + 9.4%, P = 0.02). Conclusion: The role of increased myocardial contractility and decreased cardiac filling is not confirmed in the present study. [source] Abnormality of the Left Ventricular Sympathetic Nervous Function Assessed by I-123 Metaiodobenzylguanidine Imaging in Pediatric Patients with Neurocardiogenic SyncopePACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 10 2003RANA OLGUNTÜRK The purpose of this study was to assess the left ventricular sympathetic nervous system function in the patients with neurocardiogenic syncope (NCS) using I-123 metaiodobenzylguanidine (MIBG) imaging of the heart, and to compare the plasma noradrenaline (NA) and MIBG results of tilt positive and tilt negative patients following a head-up tilt test (HUT). The study included 30 patients. Their physical and laboratory examinations did not show a pathology that may be the cause of their syncope. HUT test was positive in 13 patients and negative in 17 patients. Plasma NA concentrations were higher in the HUT positive than the HUT negative group at the beginning and at the 10th minute of the test. Specific I-123 MIBG uptake assessed as the cardiac to mediastinal activity ratio in the delayed image was significantly higher in HUT positive group. The higher levels of MIBG uptake and plasma NA observed in HUT positive patients may reflect the greater capacity of NA storage in cardiac adrenergic neuronal tissue in patients with NCS. The results of this study support the critical role of autonomic nervous system in the pathophysiology of NCS and the excessive sympathetic nervous stimulation as the trigger of paradox reflex. (PACE 2003; 26:1926,1930) [source] Physiologic neurocirculatory patterns in the head-up tilt test in children with orthostatic intolerancePEDIATRICS INTERNATIONAL, Issue 2 2008Zhang Qingyou Abstract Background: Orthostatic intolerance (OI) is a common clinical manifestation in clinical pediatrics. The head-up tilt (HUT) table test is considered the standard of orthostatic assessment, but the physiologic neurocirculatory profile during HUT has not been fully realized in children with OI. The present study, therefore, was designed to investigate the physiologic patterns that occur during HUT in children with OI. Methods: Ninety children (56 girls; mean age, 11.6 ± 2.3 years) with OI underwent HUT under quiet circumstances. Blood pressure and heart rate were monitored simultaneously. Results: Forty-nine children with OI (54.4%) had vasovagal response with HUT testing; 33 (36.7%), vasodepressor response; six (6.7%), cardioinhibitory response; and 10 (11.1%), mixed response. Twenty-eight children (31.1%) had postural orthostatic tachycardia; one (1.1%), orthostatic hypotension (OH); and 12 (13.3%), normal physiologic response. Patterns of cerebral syncope response and chronotropic incompetence were not observed. Conclusions: Classical vasovagal response was the major physiologic pattern seen in children with OI during HUT testing, and postural orthostatic tachycardia response ranked second. [source] Long-Term Follow-Up of Patients with Syncope Evaluated by Head-Up Tilt TestANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 2 2010Giulia Domenichini M.D. Background: Clinicians may be tempted to consider a positive head-up tilt test (HUTT) an unfavorable prognostic indicator. We investigated whether results of routine HUTT predict long-term recurrence of syncope. Methods: We analyzed syncope recurrence at long-term among 107 patients (mean age 51 ± 20 years) receiving HUTT for diagnostic evaluation of unexplained/suspected neurocardiogenic syncope in our Institute. Results: HUTT was positive in 76 patients (vasodepressive response, n = 58; cardioinhibitory, n = 5; mixed, n = 13). During a median follow-up of 113 months (range, 7,161), 34 (32%) patients experienced recurrence (24 [32%] with positive HUTT during 110 months (7,159); 10 [32%] with negative HUTT during 120 [22,161] months). Actuarial freedom from recurrence at 10 years did not significantly differ for patients with positive/negative test results (after passive/active phases) or with different positive response patterns (vasodepressive, cardioinhibitory, mixed). By contrast, history of >4 syncopes in the 12 months preceding HUTT stratified risk of recurrence, irrespective of HUTT positivity/negativity. At Cox proportional hazards analysis, history of >4 syncopes in the 12 months preceding HUTT was the single independent risk factor for recurrence both in the overall study population (HR, 1.7; 95% CI, 1.07,2.69) and within the subset of patients who tested positive (HR, 1.83; 95% CI, 1.07,3.17). Conclusions: This long-term follow-up study reinforces the concept that a positive HUTT should not be considered an unfavorable prognostic indicator; frequency of recent occurrences may be a more valid predictor. Ann Noninvasive Electrocardiol 2010;15(2):101,106 [source] ,-Adrenoceptor agonists for the treatment of vasovagal syncope: a meta-analysis of worldwide published dataACTA PAEDIATRICA, Issue 7 2009Ying Liao Abstract Aim:, The present study was aimed at evaluating present randomized controlled trials (RCTs) regarding the effect of ,-adrenoceptor agonists on vasovagal syncope (VVS). Methods:, According to inclusion and exclusion criteria, articles were selected from medical electronic databases. RCTs were then assessed based on the Juni assessment, and meta-analysis was completed using the Review Manager 4.2 software. Indication to further evaluate effects was the recurrence of syncope during follow-up treatment or a response in the head-up tilt test (HUT) after treatment. The results were stated as odd ratio (OR), with a 95% confidence interval (CI) and a p < 0.05 significant level. Results:, In total, six RCTs were selected. Funnel plot analysis showed possible publication bias. Meta-analysis of the six RCTs, including all 165 patients in the treatment group and 164 patients in the control group, indicated that ,-adrenoceptor agonists were more effective than placebos in treating VVS (OR = 0.21, 95% CI: 0.06,0.77, p = 0.02). The further, weighted independent t- test disclosed that the weighted mean percentage of responders for midodrine (76.3%± 7.7%) was significantly higher than that for etilefrine (65.5%± 15.4%) (t = 5.863, p < 0.001). Conclusion:, The currently published RCTs support that ,-adrenoceptor agonists might be effective for VVS. Midodrine can be regarded as a better choice compared with etilefrine. [source] Hemodynamic significance of heart rate in neurally mediated syncopeCLINICAL CARDIOLOGY, Issue 11 2004Wan Leong Chan M.D. Abstract Background: Vasovagal and vasodepressor syncope are used interchangeably in the literature to describe the common faint syndrome, now collectively named neurally mediated syncope. The significance of heart rate (HR) in these reflex-induced reactions remains unclear. Hypothesis: The study was undertaken to investigate the hemodynamic significance of HR in tilt-induced neurally mediated syncope. Methods: In all, 113 patients with syncope of unknown etiology were studied by head-up tilt test with invasive hemodynamic monitoring. Thirty-five patients (15 women, 20 men, age range 21 to 72 years) developed syncope and were enrolled for analysis. The hemodynamic data were compared between patients who developed bradycardia (vasovagal group, n = 15) and those without bradycardia (vasodepressor group, n = 20). Results: The baseline hemodynamic data (mean ± standard deviation) and the hemodynamic responses after 10-min head-up tilt were similar between patients in the vasovagal and vasodepressor groups. During syncope, patients with vasovagal reaction developed hypotension and paradoxical bradycardia (HR = 52.4 ± 5.9 beats/min), while patients with vasodepressor reaction developed a precipitous drop in arterial blood pressure with inappropriate HR (105 ± 21 beats/min) compensation. Patients with vasovagal syncope manifested a significantly lower cardiac index and a significantly higher systemic vascular resistance index than patients with vasodepressor syncope (1.47 ±0.29 vs. 1.97 ±0.41 l/min/m2, p< 0.001 and 2098 ± 615 vs. 1573 ± 353 dynes·s·cm,5·m2, p<0.003, respectively). A positive correlation existed between HR and cardiac index (r = 0.44, p = 0.008) during syncope in the patients studied. Conclusions: These findings suggest that the hemodynamic characteristics of vasovagal and vasodepressor reactions are different, and that HR plays a significant role in neurally mediated syncope. [source] | ||||||||||||||||||||||