OBJECTIVE: To analyze the disease spectrums underlying orthostatic intolerance (OI) and sitting intolerance (SI) in Chinese children, and to understand the clinical empirical treatment options. METHODS: The medical records including history, physical examination, laboratory examination, and imagological examination of children were retrospectively studied in Peking University First Hospital from 2012 to 2021. All the children who met the diagnostic criteria of OI and SI were enrolled in the study. The disease spectrums underlying OI and SI and treatment options during the last 10 years were analyzed. RESULTS: A total of 2 110 cases of OI and SI patients were collected in the last 10 years, including 943 males (44.69%) and 1 167 females (55.31%) aged 4－18 years, with an average of (11.34±2.84) years. The overall case number was in an increasing trend over the year. In the OI spectrum, postural tachycardia syndrome (POTS) accounted for 826 cases (39.15%), followed by vasovagal syncope (VVS) (634 cases, 30.05%). The highest proportion of SI spectrum was sitting tachycardia (STS) (8 cases, 0.38%), followed by sitting hypertension (SHT) (2 cases, 0.09%). The most common comorbidity of OI and SI was POTS coexisting with STS (36 cases, 1.71%). The highest proportion of treatment options was autonomic nerve function exercise (757 cases, 35.88%), followed by oral rehydration salts (ORS) (687 cases, 32.56%), metoprolol (307 cases, 14.55%), midodrine (142 cases, 6.73%), ORS plus metoprolol (138 cases, 6.54%), and ORS plus midodrine (79 cases, 3.74%). The patients with POTS coexisting with VVS were more likely to receive pharmacological intervention than the patients with POTS and the patients with VVS (41.95% vs. 30.51% vs. 28.08%, χ²= 20.319, P < 0.01), but there was no significant difference in the proportion of treatment options between the patients with POTS and the patients with VVS. CONCLUSION POTS and VVS in children are the main underlying diseases of OI, while SI is a new disease discovered recently. The number of children with OI and SI showed an increasing trend. The main treatment methods are autonomic nerve function exercise and ORS. Children with VVS coexisting with POTS were more likely to take pharmacological treatments than those with VVS or POTS only.
Child ; Electrolytes ; Female ; Humans ; Male ; Metoprolol ; Midodrine ; Orthostatic Intolerance/therapy* ; Postural Orthostatic Tachycardia Syndrome/diagnosis* ; Retrospective Studies ; Salts ; Sitting Position ; Syncope, Vasovagal/diagnosis* ; Tilt-Table Test

Objective: To investigate the clinical value of coefficient of variation of heart rate and blood pressure in rapid identification of children with suspected orthostatic intolerance(OI). Methods: This was a retrospective study. The medical records of 379 children with OI were collected, who were admitted to the Department of Pediatrics of Qilu Hospital of Shandong University from January 2015 to January 2020. Another 20 out-patient children without syncope or syncope aura were selected as control. According to the results of standing test and head-up tilt test (HUTT), all the patients with OI were divided into the following 4 groups: vasovagal syncope (VVS) group, postural tachycardia syndrome (POTS) group, POTS combined with VVS (POTS+VVS) group and HUTT negative group. Then, coefficient of variation of systolic pressure (SBP_CV), coefficient of variation of diastolic pressure (DBP_CV) and coefficient of variation of heart rate (HR_CV) in standing test and HUTT were calculated. Kruskal-Wallis test was used for comparison among the five groups, and Dunnett's T3 method for comparison between two groups. Paired t test was used to compare the coefficient of variation between supine and erect position and tilt position in each group. The predictive values of HR_CV,SBP_CV and DBP_CV for negative HUTT were evaluated by receiver operating characteristic (ROC) curve. Results: Among the 379 children, there were 79 in HUTT negative group, 208 in VVS group, 52 in POTS group, and 40 in POTS+VVS group. The SBP_CV of supine-erect position of the control group, HUTT negative group, VVS group, POTS group, POTS+VVS group were (3.8±1.0)%, (5.3±2.2)%, (6.6±3.4)%, (5.9±3.6)%, (6.9±2.8)%, respectively. Similarly, the SBP_CV of supine, erect and head-up tilt position were (4.5±0.8)%, (6.0±1.9)%, (7.1±2.6)%, (6.0±2.1)%, (7.3±2.5)%; the DBP_CV of supine-erect position were (7.3±1.2)%, (9.1±3.7)%, (9.1±4.9)%, (9.1±4.8)%, (11.6±4.6)%; the DBP_CV of supine, erect and tilt position were (7.4±1.1)%, (9.4±2.9)%, (10.1±3.8)%, (9.2±3.3)%, (11.0±4.7)%; the HR_CV of supine-erect position were (7.6±2.6)%, (12.9±3.7)%, (16.2±4.3)%, (21.2±5.9)%, (24.9±5.3)%; and the HR_CV of supine, erect and tilt position were (8.1±1.6)%, (10.1±2.7)%, (14.1±4.3)%, (15.6±3.7)%, (18.9±4.0)%, respectively. All the indexes showed significant differences among the five groups (χ²=21.91, 25.47, 19.82, 14.65, 104.52, 92.51, all P<0.05). ROC curve analysis showed that when the SBP_CV and HR_CV of supine-erect position reached 4.4% and 10.5%, the area under the curve of ROC were 0.713 and 0.877, the sensitivity of predicting negative HUTT were 58.2% and 78.5%, and the specificity were 80.0% and 95.0%, respectively. Conclusions: Coefficient of variation of heart rate and blood pressure may serve as potential diagnostic indexes in evaluating autonomic function of OI patients. SBP_CV ≥ 4.4% or HR_CV ≥ 10.5% of supine-erect position could be an indication of HUTT.
Blood Pressure ; Child ; Heart Rate ; Humans ; Orthostatic Intolerance/diagnosis* ; Postural Orthostatic Tachycardia Syndrome/diagnosis* ; Retrospective Studies ; Syncope, Vasovagal/diagnosis* ; Tilt-Table Test

Orthostatic dizziness is a common dizziness syndrome characterized by nonvertiginous lightheadedness when patients rise to stand from a sitting or supine position. Orthostatic dizziness is commonly believed to derive from orthostatic hypotension (OH) or postural tachycardia syndrome (POTS). Tilt-table test and Valsalva maneuver are standardized methods for evaluating of adrenergic autonomic function and essential for diagnosis of OH and POTS. We described the guidelines and interpretations of the tilt-table test and Valsalva maneuver.
Diagnosis ; Dizziness ; Humans ; Hypotension, Orthostatic ; Postural Orthostatic Tachycardia Syndrome ; Supine Position ; Tilt-Table Test ; Valsalva Maneuver

The general concept and initial approach to syncope patients has been mentioned in the general sections. This special sections have been described the characteristics, diagnosis, and treatment with patient education for the each syncope. It has been described in order of reflex syncope, orthostatic hypotension, postural orthostatic tachycardia syndrome (POTS), cardiac syncope, and unexplained syncope. Several clinical issues will have been dealt with in special issues. Neurological assessment is added when the patients were diagnosed with psychogenic pseudosyncope (PPS). Although many childhood syncope caused by reflex syncope, they are also presented as syncope caused by arrhythmic events in patients with congenital heart disease. In the elderly patients, syncope is because of not only a single cause of syncope but a combination of various conditions. In case of a syncope patient visiting the emergency department, a standardized systematic approach will be required to determine whether hospitalize the patient according to the risk of recurrence and the needs for the syncope management unit. We also mention recommendations on the limits of driving, exercising and social life style that are relevant to syncope in all patients. In this guideline, we reviewed the Korean published literatures and European/American guidelines on syncope. We, writing and publishing committee for evaluation and management guidelines of syncope in the Korean Society for Holter and Noninvasive Electrocardiography (KSHNE) under the Korean Heart Rhythm Society (KHRS) are very pleased to be able to publish this guideline. We also hope this guideline will be a good support to manage the syncope patients and a useful trigger for further research in Korea.
Aged ; Diagnosis ; Electrocardiography ; Emergency Service, Hospital ; Heart ; Heart Defects, Congenital ; Hope ; Humans ; Hypotension, Orthostatic ; Korea ; Life Style ; Patient Education as Topic ; Postural Orthostatic Tachycardia Syndrome ; Recurrence ; Reflex ; Syncope ; Writing

PURPOSE: The clinical characteristics and neuropsychological tests of orthostatic hypotension (OH) and postural orthostatic tachycardia syndrome (POTS) in children were compared. METHODS: From August 2011 to April 2015, we enrolled patients who visited hospital with dizziness or syncope. According to the results of head-up tilt test (HUTT), the patients were classified into 4 groups; OH group, POTS group, normal group I who had no orthostatic symptom during HUTT, and normal group II who had orthostatic symptom during HUTT. RESULTS: Eighty-eight patients were enrolled with 11(12.5%) in OH group, 13(14.7%) in POTS group, 49(55.7%) in normal group I and 15(17.0%) in the normal group II. During HUTT, the temporal changes of systolic, diastolic, and mean blood pressure of OH group were significantly different from those of POTS group, normal group I, and normal group II. Heart rate changes after tilt showed increase trend in all 4 groups and there was no significant different between OH and POTS group. In normal group II, the temporal changes of diastolic and mean blood pressure were similar to those in POTS group and were significantly different from normal group I. In the autonomic nervous system test, the heart rate response to deep breathing (HRDB) was significantly different between normal group I and II CONCLUSIONS: In pediatric OH patients, heart rate may be increased with blood pressure fall. And if orthostatic symptoms are associated with HUTT, we should not exclude OI even if the test result do not meet the criteria for diagnosis.
Autonomic Nervous System ; Blood Pressure ; Child* ; Diagnosis ; Dizziness ; Heart Rate ; Humans ; Hypotension, Orthostatic* ; Neurophysiology* ; Neuropsychological Tests ; Postural Orthostatic Tachycardia Syndrome* ; Respiration ; Syncope

Orthostasis means standing upright. Thus, orthostatic intolerance (OI) can be simply defined as “the development of symptoms during upright standing, that are relieved by recumbency.” However, OI might be a confusing topic in clinical practice because of the recent appreciation of the condition's clinical variant, emerging understanding of its diverse mechanisms, and its nomenclature, which seems to change annually. OI is not fatal but should be differentiated from potentially lethal disorders, including seizures or cardiogenic syncope. Typical signs and symptoms include loss of consciousness, lightheadedness, and visual difficulties. However, patients also experience multiple and nonspecific symptoms that seem unrelated to orthostatic intolerance, such as headache, fatigue, nausea, abdominal pain, and exercise intolerance. This review was aimed at expanding the comprehension of this confusing and easily missed topic by providing better understanding of the normal hemodynamic response to orthostasis and the basic pathophysiological concepts of major syndromes of OI.
Abdominal Pain ; Child ; Comprehension ; Diagnosis* ; Dizziness ; Fatigue ; Headache ; Hemodynamics ; Humans ; Hypotension, Orthostatic ; Nausea ; Orthostatic Intolerance* ; Postural Orthostatic Tachycardia Syndrome ; Seizures ; Syncope ; Unconsciousness

Biomarkers ; Child ; Humans ; Postural Orthostatic Tachycardia Syndrome ; diagnosis

Child ; Humans ; Postural Orthostatic Tachycardia Syndrome ; diagnosis ; Tilt-Table Test

BACKGROUNDThe incidence of postural tachycardia syndrome (POTS) has been increasing in children and adolescents, while clinical characteristics of POTS in the pediatric population are not fully understood.

METHODSAn observational study was performed in 150 pediatric patients aged between 5 and 18 years who underwent head-up tilt test (HUTT) with the diagnosis of POTS at Peking University First Hospital from March 2008 to August 2013. Demographic data, clinical presentation, autonomic parameters, laboratory findings, and treatments were recorded.

RESULTSPOTS in children commonly occurred in the age of 7-14 years. Dizziness (84.00%) was the most common symptom, followed by weakness (72.00%) and orthostatic syncope (62.67%). Positive family history of orthostatic intolerance (OI) was found in 24.64% of children with POTS. And 33.09% of them had preceding infection history as precipitating events. Ten percent of them suffered from orthostatic hypertension. Hyperadrenergic status was documented in 51.28% of 39 patients who were tested for the standing norepinephrine levels. More than half of POTS patients, with 24-hour urinary sodium level <124 mmol/24 hours, were suitable for treatment of salt supplementation. At least 25.74% of POTS patients were of positive acetylcholine receptor (AChR) antibody. Low iron storage in children with POTS was relatively rare. Most patients responded well to treatments, 43.51% of patients recovered, while 7.63% of them had relapse after symptoms disappeared.

CONCLUSIONSPOTS is a relatively common condition with complex pathophysiology and heterogeneous clinical manifestation. A comprehensive therapeutic regimen is recommended for the treatment.

Adolescent ; Blood Pressure ; physiology ; Child ; Child, Preschool ; Exercise Therapy ; methods ; Female ; Heart Rate ; physiology ; Humans ; Male ; Postural Orthostatic Tachycardia Syndrome ; diagnosis ; drug therapy ; therapy ; urine ; Retrospective Studies ; Salts ; therapeutic use ; Sodium ; urine

BACKGROUNDPostural orthostatic tachycardia syndrome (POTS) is a common clinical problem in children and adolescents. The previous diagnostic approach to POTS of children and adolescents is based on a series of tests to exclude all other causes, which is time and medical resource consuming. Recently, a new diagnostic approach has been developed. The present study was designed to statistically analyze the results of clinical investigation items and the cost for the diagnosis of POTS in children patients, and evaluate cost changes in the diagnosis of POTS.

METHODSA total of 315 children patients were divided into two groups according to diagnosis period, including group I diagnosed in 2002 - 2006 (100 cases) and group II in 2007 - 2010 (215 cases) and the diagnostic item-based distribution of the cost was analyzed. The diagnostic costs were compared between two groups using SPSS17.0.

RESULTSThe per-capita cost of diagnosis in group I was (621.95 ± 21.10) Yuan, costs of diagnostic tests (head-up tilt test, standing test, etc) accounted for 8.68% and the exclusive tests for 91.32%. The per-capita cost of diagnosis in group II was (542.69 ± 23.14) Yuan, diagnostic tests accounted for 10.50% and exclusive tests for 89.50%. Comparison of the total cost of diagnostic tests between the two groups showed significant differences (P < 0.05).

CONCLUSIONThe cost of POTS diagnosis has been declined in recent years, but the cost of exclusive diagnosis is still its major part.

Adolescent ; Asian Continental Ancestry Group ; Child ; Child, Preschool ; Diagnostic Tests, Routine ; economics ; Female ; Humans ; Male ; Postural Orthostatic Tachycardia Syndrome ; diagnosis ; economics ; Public Health ; economics