Head-up Tilt Table Test Results Research Articles

Evaluation of syncope in patients referred to afshar heart clinic, yazd, iran from september 2016 to march 2017

Objectives: Syncope is defined as a sudden and transient loss of consciousness followed by complete spontaneous recovery. This study describes the syncope evaluation in patients referred to the Heart Clinic.
 Methods: This descriptive cross-sectional study was conducted on 60 syncope patients referred to Afshar Heart Clinic of Yazd, Iran, from September 2016 to March 2017. After performing clinical workups, the etiology of syncope was diagnosed in each patient. Electrocardiography and blood pressure measurements were done for all patients. Additional clinical tests, including echocardiography, Holter Monitoring, Head-Up tilt table test (HUTT), electroencephalography, and Magnetic Resonance Imaging, were performed for some patients based on the cardiologist's opinion. The distribution of patient's clinical records, such as age, sex, diabetes, hypertension, history of ischemic heart disease (IHD), duration of syncope, postdrome, prodromal symptoms, and clinical test results according to causes of syncope in patients, were reported.
 Results: Sixty patients with a mean age of 50.7 ± 20.4 years were evaluated (55% male). Thirty-five patients (58.3%) had Neurally Mediated Syncope, 18 patients (30%) had arterioventricular (AV) Block induced syncope, and 7 (11.7%) patients had Sick Sinus Syndrome (SSS) induced syncope. Age, hypertension, prodromal symptoms, history of IHD, ECG, Holter monitoring, and HUTT results were associated with the cause of the syncope.
 Conclusions: Cardiac syncopes (AV-Block induced and SSS induced) were related to older age, hypertension, abnormal electrocardiogram, and abnormal Holter monitoring results. Neurally mediated syncope was associated with younger age, prodromal symptoms, and abnormal HUTT results.

Frontal lobe hemodynamics detected by functional near-infrared spectroscopy during head-up tilt table tests in patients with electrical burns.

SignificanceElectrical burns can cause severe damage to the nervous system, resulting in autonomic dysfunction with reduced cerebral perfusion. However, few studies have investigated these consequences.AimTo elucidate changes in prefrontal cerebral hemodynamics using functional near-infrared spectroscopy (fNIRS) during the head-up tilt table test (HUT) for patients with electrical burns.ApproachWe recruited 17 patients with acute electrical burns within 1 week after their accidents and 10 healthy volunteers. The NIRS parameters acquired using an fNIRS device attached to the forehead were analyzed in five distinct HUT phases.ResultsBased on their HUT response patterns, patients with electrical burns were classified into the group with abnormal HUT results (APG, n = 4) or normal HUT results (NPG, n = 13) and compared with the healthy control (HC, n = 10) participants. We found trends in hemodynamic changes during the HUT that distinguished HC, NPG, and APG. Reduced cerebral perfusion and decreased blood oxygenation during the HUT were found in both the NPG and APG groups. Patients with electrical burns had autonomic dysfunction compared to the HC participants.ConclusionsUsing fNIRS, we observed that acute-stage electrical burn injuries could affect cerebral perfusion.

Repolarization disparity as a predictor of response to Head up Tilt-table Test in pediatric syncope.

Head up Tilt-table Test (HUTT) is a practical examination of the most common type of pediatrics syncope. The electrocardiographic (ECG) changes during this test, show the autonomic defects that cause neuraly-mediated syncope in response to tilting process. All pediatric syncope patients referred to our center in a 1-year period, were included in the study. HUTT was performed and patients were classified into two groups of Negative and Positive HUTT results, and the latter group was subclassified as three subgroups of "vasodepressor", "cardioinhibitory" and "mixed type" responses to HUTT. QT and corrected QT (QTc) dispersion was measured by the baseline standard 12-lead ECG obtained before HUTT. Eighty-six patients with a mean age of 12.19 ± 5.34 were included. Patients with positive HUTT were significantly younger and male gender was more prevalent in this group. Mean QT dispersion was significantly higher in patients with positive HUTT result and also in patients with mixed response to HUTT compared to isolated vasodepressor response. Duration of QTc interval did not change between different study groups. Reciever-Operating-Characteristic (ROC) analysis showed that QT dispersion higher than 32ms is a significant predictor of positive HUTT result (with 92% sensitivity and 98% specificity) and values higher than 40ms can predict the mixed type of response to HUTT (with 84% sensitivity and 63% specificity). Baseline myocardial repolarization disparity significantly correlates with susceptibility to symptomatic vasovagal syncope. This pathology seems to play its role mainly via excessive vagotonic response to sympathetic activation during HUTT process (known as cardioinhibitory response).

Fludrocortisone in Pediatric Vasovagal Syncope: A Retrospective, Single-Center Observational Study.

Background and PurposeThe purpose of this study was to determine the effect of fludrocortisone in patients with pediatric vasovagal syncope (VVS).MethodsThis retrospective observational single-tertiary-center study based on chart reviews included 74 patients who were newly diagnosed with VVS in the head-up tilt-table test (HUTT). Some of the patients had been treated with fludrocortisone. All patients were assessed using a brain and cardiac workup before treatment to rule out the syncope being due to other causes, which resulted in seven of them being excluded: two for epilepsy and five for brain pathologies. The remaining 67 patients were analyzed. The effect of fludrocortisone was evaluated based on the results of a follow-up HUTT, with a response to the treatment considered to be present if there was a negative change at the follow-up HUTT. Univariate logistic regression were used for statistical analyses, with the criterion for significance being p<0.05.ResultsThere were no significant differences in the characteristic of the patients between the no-medication (n=39) and fludrocortisone (n=28) groups, including age, sex, and duration of treatment. The recurrence rate of syncopal or presyncopal events was significantly lower in the fludrocortisone group (39.3%, 11 of 28) than in the no-medication group (64.1%, 25 of 39) (p=0.044), as was the rate of negative change at the follow-up HUTT: 57.1% (16 of 28) and 28.2% (11 of 39), respectively (p=0.017).ConclusionsOur findings suggest that fludrocortisone is more effective than no medication in pediatric patients with VVS.

Regional analysis of cerebral hemodynamic changes during the head-up tilt test in Parkinson's disease patients with orthostatic intolerance.

.Significance: Cerebral oxygenation changes in the superior, middle, and medial gyri were used to elucidate spatial impairments of autonomic hemodynamic recovery during the head-up tilt table test (HUTT) in Parkinson’s disease (PD) patients with orthostatic intolerance (OI) symptoms.Aim: To analyze dynamic oxygenation changes during the HUTT and classify PD patients with OI symptoms using clinical and oxygenation features.Approach: Thirty-nine PD patients with OI symptoms [10: orthostatic hypotension (PD-OH); 29: normal HUTT results (PD-NOR)] and seven healthy controls (HCs) were recruited. Prefrontal oxyhemoglobin (HbO) changes during the HUTT were reconstructed with diffuse optical tomography and segmented using the automated anatomical labeling system. Decision trees were used for classification.Results: HCs and PD-NOR patients with positive rates of HbO change (PD-POS) showed the greatest HbO recovery in the superior frontal gyrus (SFG) during tilt. PD-OH and PD-NOR patients with negative rates of HbO change (PD-NEG) showed asymmetric reoxygenation. The classification accuracy was 89.4% for PD-POS versus PD-NEG, 71% for PD-NOR versus PD-OH, and 55.8% for PD-POS versus PD-NEG versus PD-OH. The oxygenation features were more discriminative than the clinical features.Conclusions: PD-OH showed decreased right SFG function, which may be associated with impaired compensatory autonomic responses to orthostatic stress.

P1101Is there any link between vitamin D deficiency and vasovagal syncope?

Abstract Background This study aimed to investigate serum 25[OH]D levels between patients with vasovagal syncope(VVS) diagnosed by head-up tilt table test (HUTT) and patients who do not develop syncope during the test. Methods Sixty-eight consecutive patients [mean age 33.2 ± 14.5 years, 49 females (72.1%)] were categorized based on their HUTT results (positive vs. negative, n = 40 vs. 28).25[OH]D levels were measured by chemiluminescent microparticle immunoassay method in all patients. Results There was no difference between the two groups in terms of blood tests, Body Mass Index, gender, echocardiographic findings(p &amp;gt; 0.05).Mean 25[OH]D level was lower in HUTT positive patients when compared to the HUTT negative group(p &amp;lt; 0.05).25[OH]D levels were significantly lower between patients over the age 25 in two groups (mean level 17.9 ± 7.3 vs 26.3 ± 8.5, respectively,p &amp;lt; 0.005).(Table 1) Conclusion We found that patients diagnosed VVS by HUTT test had lower 25[OH]D levels.Measurement of vitamin D level may be an important factor in VVS patients. Table 1 Head-up Tilt Testing positive (n = 40) negative (n = 28) p value Age (years) 33.2 ± 13.7 33.3 ± 15.9 0.973 Female gender (%) 31 (77.5) 18(64.3) 0.232 BMI (kg/m2) 23.4 ± 3.1 23.0 ± 2.6 0,596 EF (%) 59.2 ± 1.6 59.1 ± 1.3 0.357 LA (mm) 34 ± 2.4 33 ± 2.7 0.715 RA (mm) 32 ± 2.5 31 ± 2.7 0.141 Vitamin D (ng/mL) 16.5 ± 6.6 23.9 ± 9.5 0.001 Vitamin B12 (pg/mL) 355.1 ± 124.6 378 ± 87.0 0.367 TSH (mIU/L) 1.8 ± 0.8 1.7 ± 0.9 0.367 Glucose (mg/dL) 87.0 ± 7.4 90.5 ± 8.1 0.076 Creatinine (mg/dL) 0.6 ± 0.1 0.7 ± 0.1 0..55 Sodium (mmol/L) 139.8 ± 2.0 139.7 ± 2.5 0.931 Potassium (mmol/L) 4.1 ± 0.3 4.1 ± 0.2 0.674 Calcium (mg/dL) 8.9 ± 0.9 8.9 ± 1.1 0.476 Wbc (x103/uL) 7.3 ± 1.6 6.9 ± 1.6 0.339 Hb (g/dL) 13.3 ± 1.3 13.5 ± 1.8 0.664 Age (years) Vitamin D level Vitamin D level 0.132 ≤ 25 (n = 31) 14.8 ± 5.5 21.2 ± 10.2 0.057 &amp;gt; 25 (n = 37) 17.9 ± 7.3 26.3 ± 8.5 0.005 Patients characteristics of Head-up Tilt Testing positive and negative group

Cerebral Perfusion Monitoring Using Near-Infrared Spectroscopy During Head-Up Tilt Table Test in Patients With Orthostatic Intolerance.

The head-up tilt table test (HUT) is one of the primary clinical examinations for evaluating orthostatic intolerance (OI). HUT can be divided into three phases: dynamic tilt phase (supine to tilt up), static tilt phase (remain tilted at 70°), and post tilt phase (tilt down back to supine position). Commonly, blood pressure (BP) and heart rate (HR) are monitored to observe for OI symptoms, but are indirect measurements of cerebral perfusion and can lead to inaccurate HUT evaluation. In this study, we implemented a 108-channel near-infrared spectroscopy (NIRS) probe to characterize HUT performance by monitoring cerebral hemodynamic changes for healthy controls (HCs), OI patients with normal HUT results, and OI patients with positive HUT results: vasovagal syncope (VS), postural orthostatic tachycardia syndrome (POTS), orthostatic hypotension (OH), and orthostatic hypertension (OHT). By the end of the static tilt phase, OI patients typically did not show a complete recovery back to baseline cerebral oxygenation and total blood volume compared to HCs. We characterized the return to cerebral homeostasis by polynomial fitting total blood volume changes and determining the inflection point. The OI patients with normal HUT results, VS, OH, or OHT showed a delay in the return to cerebral homeostasis compared to the HC group during HUT.

The relationship of fasting glucose in basic state with the results of head-up tilt table test in children

Objective To explore the relationship of fasting glucose in basic state with the results of head-up tilt table test (HUTT) in children.Methods We choosed 157 cases of children (male 86 and female 71) with unexplained syncope,headache,dizziness and sigh,they were 3 ～ 18 (11.34 ± 3.29) years old and were outpatients or had been hospitalized in the Second Xiangya Hospital of Central South University from Sep 2012 to Feb 2013.The HUTT were carried on after eliminate organic disease of heart,head,bloodvessel and other reasons caused by the above symptoms and obtain written informed consent from participants or guardian.Before HUTI,trace fasting glucose of children would be monitored in based condition.Results (1) Between HUTT negative group (n =63) and HUTT positive group (n =94),there was no significant difference in fasting glucose [(5.40 ± 0.52) mmol/L vs (5.35 ± 0.61) mmoL/L,t =-0.590,P ＞ 0.05].(2) Only 1 case of heart inhibited type vasovagal syncope did not be included in 94 children with HUTT positive.There were no significant differences in fasting glucose between vascular inhibited type vasovagal syncope (n =67) and mixed vasovagal syncope (n =10) and orthostatic tachycardia syndrome (n =16)[(5.34 ±0.54) mmol/L vs (5.07 ±0.64) mmol/L vs (5.49 ±0.81) mmol/L,P ＞0.05].(3) Among 67 cases of vascular inhibitory type vasovagal syncope in children,two kinds induced way of based tilt table test (n =16) and sublingual nitroglycerin tilt table test (n =51) showed no significant differences in fasting glucose [(5.32 ±0.54) mmol/L vs (5.35 ±0.55) mmol/L,t =0.166,P ＞0.05].(4) In two groups of fasting glucose ＜5.5 mmol/L and ≥5.5 mmol/L,HUTT negative rate [37.63％ (35/93) vs 43.75％ (28/64)] and HUTT positive rate [62.37％ (58/93) vs 56.25％ (36/64)] showed no statistical significance (x2 =0.585,P ＞ 0.05).Conclusion Fasting glucose in basic state has no predictive value to HUTT results in children. Key words: Fasting glucose; Head-up tilt table test; Children

Efficacy and Safety of Clonazepam in Refractory Neurally Mediated Syncope

Neurally mediated syncope is a complex syndrome that is often difficult to manage using currently available treatment strategies. The efficacy and safety of clonazepam was evaluated in 35 patients with refractory neurally mediated syncope. All patients had syncope (n = 33) or disabling presyncope (n = 2) and a positive head-up tilt table test (HUTT) despite treatment with one or more of the following therapies: beta-blocker, high-salt diet, fludrocortisone, elastic compression stockings, and disopyramide. Clonazepam was initiated at 0.5 mg/day and titrated in 0.25-0.5 mg/day increments for symptom control. Early (first 8 weeks) symptomatic response was achieved in 31 of 35 (89%) patients. Early HUTT reverted to negative in 29 of 35 (83%) patients. Two patients discontinued clonazepam during early follow-up due to side effects. Thirty-three patients received long-term clonazepam therapy. Twenty-five patients had late HUTT with 21 remaining negative. Of the eight patients who did not have late HUTT, one patient discontinued clonazepam prior to HUTT due to side effects. Seven patients refused late HUTT. All seven patients achieved symptomatic control on clonazepam with two requiring dose titration. Of the 21 patients with a negative late HUTT, 18 achieved symptomatic control with two of these patients requiring dose titration. Two patients who had only partial symptom control despite dose titration achieved total symptomatic control with the addition of disopyramide and beta-blockers. Two patients with a negative late HUTT discontinued clonazepam due to side effects. One patient had been symptomatically controlled while the other had recurrent symptoms with dose limiting side effects occurring after clonazepam dose titration. In the 4 patients with a positive late HUTT, 2 patients were symptomatically controlled, 1 patients required combination therapy with a beta-blocker to achieve symptomatic control, and 1 patient discontinued therapy due to side effects. Overall, 29 of 35 (83%) patients continue to receive clonazepam with symptom control. Based on intention-to-treat HUTT results, 21 of 35 (60%) patients were responders. Four patients required clonazepam dose titration and three required combination therapy with clonazepam plus disopyramide and/or a beta-blocker to achieve control. Clonazepam was discontinued in 6 patients, 5 for side effects and 1 following a transient ischemic attack. Clonazepam appears to be an effective therapeutic alternative in patients with refractory neurally mediated syncope. Based on our preliminary findings, a placebo controlled evaluation of clonazepam in neurally mediated syncope is warranted.