Tilt Test (tilt + test)

Distribution by Scientific Domains
Distribution within Medical Sciences

Kinds of Tilt Test

  • head-up tilt test


  • Selected Abstracts


    Usefulness of the Head-Upright Tilt Test for Distinguishing Syncope and Epilepsy in Children

    EPILEPSIA, Issue 6 2001
    J. Eirís-Puñal
    Summary: ,Purpose: Episodic loss of consciousness in children, whether or not associated with hypertonia or short-duration clonic movements, presents a diagnostic challenge to the pediatrician and child neurologist. We provide some evidence of the usefulness of the head-upright tilt test for investigating the causes of transient loss of consciousness in children, and for distinguishing between syncope, convulsive syncope, and epilepsy. Methods: We studied nine children previously diagnosed as epileptic on the basis of compatible clinical events and epileptiform findings in routine EEGs who were treated over the long term with antiepileptic drugs, but whose clinical records suggested syncope or convulsive syncope rather than epilepsy on reevaluation. All subjects underwent head-upright tilt testing. Results: The tilt-test result was positive in all nine cases, with the patients reporting the same symptoms as in the previously considered epileptic attacks. Conclusions: Inadequate histories and misuse/overinterpretation of EEG results often lead to misdiagnosis of epilepsy in children. The head-upright tilt test is a useful and reliable diagnostic technique, allowing syncopal events to be induced and evaluated under controlled conditions. In a subset of patients, it may help to distinguish epilepsy from simple or convulsive syncope. [source]


    Long-Term Follow-Up of Patients with Syncope Evaluated by Head-Up Tilt Test

    ANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 2 2010
    Giulia 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]


    Usefulness of the Head-Upright Tilt Test for Distinguishing Syncope and Epilepsy in Children

    EPILEPSIA, Issue 6 2001
    J. Eirís-Puñal
    Summary: ,Purpose: Episodic loss of consciousness in children, whether or not associated with hypertonia or short-duration clonic movements, presents a diagnostic challenge to the pediatrician and child neurologist. We provide some evidence of the usefulness of the head-upright tilt test for investigating the causes of transient loss of consciousness in children, and for distinguishing between syncope, convulsive syncope, and epilepsy. Methods: We studied nine children previously diagnosed as epileptic on the basis of compatible clinical events and epileptiform findings in routine EEGs who were treated over the long term with antiepileptic drugs, but whose clinical records suggested syncope or convulsive syncope rather than epilepsy on reevaluation. All subjects underwent head-upright tilt testing. Results: The tilt-test result was positive in all nine cases, with the patients reporting the same symptoms as in the previously considered epileptic attacks. Conclusions: Inadequate histories and misuse/overinterpretation of EEG results often lead to misdiagnosis of epilepsy in children. The head-upright tilt test is a useful and reliable diagnostic technique, allowing syncopal events to be induced and evaluated under controlled conditions. In a subset of patients, it may help to distinguish epilepsy from simple or convulsive syncope. [source]


    Effect of deep brain stimulation of the posterior hypothalamic area on the cardiovascular system in chronic cluster headache patients

    EUROPEAN JOURNAL OF NEUROLOGY, Issue 9 2007
    P. 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]


    Effect of Metoprolol on Quality of Life in the Prevention of Syncope Trial

    JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 10 2009
    Ph.D., ROBERT S. SHELDON M.D.
    Introduction: Vasovagal syncope is common, often recurrent, and reduces quality of life. No therapies have proven useful to improve quality of life in adequately designed randomized clinical trials. Beta-blockers have mixed evidence for effectiveness in preventing syncope. Methods: The Prevention of Syncope Trial was a randomized, placebo-controlled, double-blind, multinational, clinical trial that tested the hypothesis that metoprolol improves quality of life in adult patients with vasovagal syncope in a 1-year observation period. Randomization was stratified in strata of patients <42 and ,42 years old. The quality of life questionnaires Short Form-36 (SF-36) and Euroqol EQ-5D were completed at baseline and after 6 and 12 months of treatment by 204, 132, and 121 patients, respectively. Results: There were 208 patients, mean age 42 ± 18, of whom 134 (64%) were females. All had positive tilt tests. There was no improvement in quality of life during the trial in the entire group or in either treatment arm. Patients in the metoprolol treatment arm did not have improved quality of life compared to the patients in the placebo arm using either the SF-36 or EQ5D after either 6 or 12 months. Finally, there was no improvement in quality of life associated with metoprolol use in patients either <42 or ,42 years of age. Conclusion: Metoprolol does not improve quality of life in patients with recurrent vasovagal syncope and a positive tilt test. [source]


    Predicting Recurrence of Vasovagal Syncope: A Simple Risk Score for the Clinical Routine

    JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 4 2009
    MUHAMMET 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]


    Single-Stage Adenosine Tilt Testing in Patients with Unexplained Syncope

    JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 6 2004
    SUNEET MITTAL M.D.
    Introduction: We previously have shown that a 3-minute single-stage adenosine tilt test has a diagnostic yield comparable to a two-stage protocol consisting of a 30-minute drug-free tilt followed by a 15-minute isoproterenol tilt. In this study, we sought to further define the clinical utility of adenosine tilt testing in patients with unexplained syncope by prospectively evaluating test specificity and determining predictors of a positive test response. Methods and Results: The specificity of single-stage adenosine tilt testing was determined using 30 control subjects. To determine the diagnostic yield of this protocol, adenosine tilts were performed in 129 patients with unexplained syncope. The adenosine tilt test protocol had high specificity (100%) but a low overall diagnostic yield (18%). However, the yield was affected significantly by age. In patients ,40 years of age, the tilt test was positive in 15 (41%) of 37 patients, which was significantly greater than the yield in patients between the ages of 41 and 64 years (6/41 patients [15%], P = 0.012) and those ,65 years of age (2/41 patients [5%], P < 0.0001). Conclusion: These data support single-stage adenosine tilt testing in patients ,40 years of age because the diagnostic yield of the test is maximal in this group and the test can be completed in ,3 minutes. Conversely, the diagnostic yield of adenosine tilt testing in patients >40 years of age is low, suggesting that the clinical utility of this protocol is limited in these patients. (J Cardiovasc Electrophysiol, Vol. 15, pp. 1-4, June 2004) [source]


    Is Home Orthostatic Self-Training Effective in Preventing Neurally Mediated Syncope?

    PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 5 2007
    Ph.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 Syncope

    PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 1 2006
    PETER 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 Syncope

    PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 10 2003
    RANA 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 intolerance

    PEDIATRICS INTERNATIONAL, Issue 2 2008
    Zhang 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 Test

    ANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 2 2010
    Giulia 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 data

    ACTA PAEDIATRICA, Issue 7 2009
    Ying 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]


    Aetiologic and clinical characteristics of syncope in Chinese children

    ACTA PAEDIATRICA, Issue 10 2007
    Li 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]


    Hemodynamic significance of heart rate in neurally mediated syncope

    CLINICAL CARDIOLOGY, Issue 11 2004
    Wan 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]


    Altered cardiovascular vagal responses in nonelderly female patients with subclinical hyperthyroidism and no apparent cardiovascular disease

    CLINICAL ENDOCRINOLOGY, Issue 2 2007
    Renata Boschi Portella
    Summary Objective Subclinical hyperthyroidism (SH) has been associated with exercise intolerance, changes in cardiac morphology, atrial arrhythmias and sympathovagal imbalance. The aim of this study was to evaluate the vagal reserve and modulation by a sympathetic stimulus in nonelderly patients with SH without cardiovascular problems. Design We carried out a cross-sectional study, comparing data of the heart rate variability (HRV) of SH patients and healthy controls at rest and after vagal and sympathetic stimulation. Patients We studied 16 female patients with at least 6 months of SH and 16 healthy female controls with the same median age (40 vs. 34·5 years). Measurements We used the tilt test, with electrocardiographic record at rest, during the respiratory sinus arrhythmia (RSA) manoeuvre and after tilting, in order to analyse HRV in the frequency domain (%high frequency (HF) and low/high frequency ratio (LF/HF) using Biopotentials Captation System software. Results The median TSH level was 0·03 mU/l in patients and 1·37 mUI/l in controls. The median free T4 was 1·37 ng/dl in patients and 1·20 ng/dl in controls. Patients demonstrated a significantly smaller difference between %HF during the RSA and %HF at rest than controls (median ,7·5 vs. 36·6, P < 0·001). There was a lower difference between LF/HF ratio after tilting and LF/HF ratio at rest in patients than in controls (1·5 vs. 5·3, P = 0·005). Conclusion Subclinical hyperthyroidism affects cardiovascular autonomic balance in otherwise apparently healthy nonelderly females by blunting vagal responses. [source]


    Effect of Metoprolol on Quality of Life in the Prevention of Syncope Trial

    JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 10 2009
    Ph.D., ROBERT S. SHELDON M.D.
    Introduction: Vasovagal syncope is common, often recurrent, and reduces quality of life. No therapies have proven useful to improve quality of life in adequately designed randomized clinical trials. Beta-blockers have mixed evidence for effectiveness in preventing syncope. Methods: The Prevention of Syncope Trial was a randomized, placebo-controlled, double-blind, multinational, clinical trial that tested the hypothesis that metoprolol improves quality of life in adult patients with vasovagal syncope in a 1-year observation period. Randomization was stratified in strata of patients <42 and ,42 years old. The quality of life questionnaires Short Form-36 (SF-36) and Euroqol EQ-5D were completed at baseline and after 6 and 12 months of treatment by 204, 132, and 121 patients, respectively. Results: There were 208 patients, mean age 42 ± 18, of whom 134 (64%) were females. All had positive tilt tests. There was no improvement in quality of life during the trial in the entire group or in either treatment arm. Patients in the metoprolol treatment arm did not have improved quality of life compared to the patients in the placebo arm using either the SF-36 or EQ5D after either 6 or 12 months. Finally, there was no improvement in quality of life associated with metoprolol use in patients either <42 or ,42 years of age. Conclusion: Metoprolol does not improve quality of life in patients with recurrent vasovagal syncope and a positive tilt test. [source]