Orthostatic intolerance in adults with long COVID was not associated with postural orthostatic tachycardia syndrome

In this observational cross-sectional study, we investigated predictors of orthostatic intolerance (OI) in adults with long COVID. Participants underwent a 3-minute active stand (AS) with Finapres NOVA, followed by a 10-minute unmedicated 70-degree head-up tilt test. 85 participants were included (mean age 46 years, range 25-78; 74% women), of which 56 (66%) reported OI during AS (OIAS). OIAS seemed associated with female sex, more fatigue and depressive symptoms, and greater inability to perform activities of daily living (ADL), as well as a higher heart rate (HR) at the lowest systolic blood pressure (SBP) point before the 1st minute post-stand (mean HRnadir: 88 vs 75 bpm, P=0.004). In a regression model also including age, sex, fatigue, depression, ADL inability, and peak HR after the nadir SBP, HRnadir was the only OIAS predictor (OR=1.09, 95% CI: 1.01-1.18, P=0.027). 22 participants had initial (iOH) and 5 classical (cOH) orthostatic hypotension, but neither correlated with OIAS. 71 participants proceeded to tilt, of which 28 had OI during tilt (OItilt). Of the 53 who had a 10-minute tilt, 7 (13%) fulfilled hemodynamic postural orthostatic tachycardia syndrome (POTS) criteria, but 6 did not report OItilt. OIAS was associated with a higher initial HR on AS, which after 1 minute equalized with the non-OIAS group. Despite these initial orthostatic HR differences, POTS was infrequent and largely asymptomatic. ClinicalTrials.gov Identifier: NCT05027724 (retrospectively registered on August 30, 2021).

Evaluation of autonomic nervous system in children with spastic cerebral palsy: clinical and electophysiological study

Background Cerebral palsy (CP) is the most prevalent severe motor disability among children. The aim of this work was to assess autonomic dysfunction in children with cerebral palsy clinically and electrophysiologically. Results Age of the studied children ranged from 4 to 12 years. Quadriplegic type of spastic cerebral palsy constituted 82.5% of CP children while diplegic type constituted 17.5%. Based on Gross Motor Function Classification System (GMFCS), the majority of children were in levels 4 and 5. The prevalence of autonomic dysfunction symptoms were 80% for thermoregulatory abnormalities (cold extremities), 65% for chronic constipation, 52.5% for sleep disturbance, 47.5% for loss of appetite, 40% for sweating abnormalities, 25% for recurrent nausea and/or vomiting, 22.5% for increased sensitivity to light or dark and 15% for bloating. As regards sympathetic skin response, 19 CP children had unobtainable response in both upper and lower limbs while 5 children had unobtainable response in lower limbs only. All of them were in levels 4 and 5 of GMFCS. Postural hypotension was present in 20% of CP children. Mean Heart rate of CP children was significantly increased more than healthy children upon head tilt test. Conclusions Autonomic dysfunction has been objectively proven in CP children through absent sympathetic skin response, presence of orthostatic tachycardia and postural hypotension.

Prognostic Value of Biomarkers in Children and Adolescents With Orthostatic Intolerance

Orthostatic intolerance (OI) refers to a series of symptoms that occur during upright standing, which can be relieved when returned to the supine position. OI is a common cause of syncope in children and adolescents. In recent years, more and more studies have been carried out to assess the prognosis of OI by using biomarkers, among which, flow-mediated vasodilation, left ventricular ejection fraction and fractional shortening, hemodynamic change during head-up tilt test, detection of 24-h urinary sodium excretion, body mass index, midregional pro-adrenomedullin, and erythrocytic H2S producing rate are relatively stable, inexpensive, and easy to obtain. With the help of biomarkers, individualized treatment can be carried out to improve the long-term prognosis of children and adolescents with OI. This article reviews the prognostic value of biomarkers in children and adolescents with OI.

Comparison of cortisol levels in patients with vasovagal syncope and postural tachycardia syndrome

Objectives: To compare the levels of cortisol in patients of vasovagal syncope (VVS) and postural tachycardia syndrome (POTS). Methods: A cross-sectional analytical study was conducted at Islamic International Medical College, Rawalpindi and Electrophysiology Department at (AFIC). This study included 80 subjects, comprising of 35 patients in each group of vasovagal syncope and postural tachycardia syndrome and 10 healthy subjects. Patients with complaint of syncope was evaluated for vasovagal syncope and postural tachycardia syndrome using Head Up Tilt Test (HUTT). Blood samples of all the participants were taken and serum cortisol was analyzed using ELISA method. Results were analyzed on SPSS Statistics 21 using ANOVA with a p-value of ≤0.05 regarded as significant. Results: Hormonal analysis shows that cortisol levels in the vasovagal, postural tachycardia syndrome and in control group was 153±16.7pg/ml, 160.17±pg/ml, and 69.65±5.8pg/ml respectively. Cortisol levels were significantly higher in both vasovagal and POTS groups as compared to controls with a p-value of 0.04 and 0.023 respectively. However, there was no significant difference between vasovagal and POTS patients with p value 0.570. Conclusion: It is concluded from the study that cortisol responses of VVS and POTS were positive. doi: https://doi.org/10.12669/pjms.38.1.4122 How to cite this:Khan HF, Ambreen S, Raziq H, Hayat A. Comparison of cortisol levels in patients with vasovagal syncope and postural tachycardia syndrome. Pak J Med Sci. 2022;38(1):---------. doi: https://doi.org/10.12669/pjms.38.1.4122 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Prolonged QT interval on electrocardiogram and fainting — is there always a relationship?

Using a clinical example, the article draws the attention of doctors to the problem of the prolonged QT interval (long QT) and the related problem of fainting (syncope). Syncope is a component of long QT syndrome, and syncope is a precursor of sudden cardiac death. However, syncope in a patient with long QT syndrome may have pathogenesis that is completely unrelated to abnormalities of cardiac ion channels. In other words, such a patient may have a second disease as a syntropy relates to prolonged QT interval, to an extent mimicking long QT syndrome. The presented medical history of a 33-year-old patient S. shows the complexity of differential diagnosis of the causes of syncope. The crucial part in the diagnosis, in addition to the clinical picture, was the so-called tilt test, little-known to general medical practice, as well as the laboriousness of making a final diagnosis of the long QT Syndrome type 2, which required a molecular genetic study whole-exome sequencing. Patient S. had vasovagal syncope that not associated with long QT syndrome, but she has a risk of sudden cardiac death, and the article identifies therapeutic and other measures to reduce this risk.

Support Vector Machine-Based Classification of Vasovagal Syncope Using Head-Up Tilt Test

Syncope is the medical condition of loss of consciousness triggered by the momentary cessation of blood flow to the brain. Machine learning techniques have been established to be very effective way to address such problems, where a class label is predicted for given input data. This work presents a Support Vector Machine (SVM) based classification of neuro-mediated syncope evaluated using train–test–split and K-fold cross-validation methods using the patient’s physiological data collected through the Head-up Tilt Test in pure clinical settings. The performance of the model has been analyzed over standard statistical performance indices. The experimental results prove the effectiveness of using SVM-based classification for the proactive diagnosis of syncope.

Patients with reflex syncope have a higher prevalence of atrial fibrillation than general population which is predicted by the type of the tilt table test response

Introduction Reflex syncope is the result of an imbalance between the sympathetic and parasympathetic nervous system. The autonomic nervous system has been associated to some forms of atrial fibrillation (AF). Objective The aim of this study was to assess the prevalence of AF in patients with reflex syncope and a positive tilt table test and to identify the type of tilt test response in patients with AF in comparison to patients without AF. Methods We retrospectively studied consecutive patients that underwent a tilt table test at our institution between 2016 and 2019. We selected those patients with a positive test. Patients with an implanted pacemaker at the time of the tilt test and patients followed in a different institution were excluded. Previous diagnoses of AF episodes were assessed. We analysed the clinical characteristics and the tilt table test results according to previous history of AF. Results We studied 49 patients with a positive tilt test. Seven (14.3%) patients had previously diagnosed paroxysmal AF at the time of the tilt table test. Patients with AF were older, had more frequently hypertension, and the tilt test response was more frequently a vasodepressor than mixed or cardioinhibitory response (71.4% vs. 28.6%) (Table). In univariate analysis, age and hypertension were associated with AF, respectively, OR 1.08 (95% CI 1.01–1.17), p=0.034 and OR 10.80 (95% CI 1.19–98.36), p=0.035. A vasodepressor response was also associated with AF (OR 6.25, 95% CI 1.06–36.74, p=0.043). Conclusions Patients with reflex syncope and a positive tilt table test had a higher prevalence of AF than the general population. A vasodepressor response was associated with AF as were age and hypertension, demonstrating the possible impact of the autonomic nervous system and the multifactorial nature of AF. FUNDunding Acknowledgement Type of funding sources: None.