|
 
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| ORIGINAL ARTICLE |
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| Year : 2020 | Volume
: 4
| Issue : 3 | Page : 75-79 |
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The role and importance of the tilt table test in pediatrics: Single-center experience and review of literature
Zijo Begic1, Nedim Begic1, Edin Begic2, Naida Spahovic3
1 Department of Cardiology, Paediatric Clinic, Clinical Center University of Sarajevo, Sarajevo, Bosnia and Herzegovina
2 Department of Cardiology, General Hospital ''Prim.dr Abdulah Nakaš''; Department of Pharmacology, School of Medicine, Sarajevo School of Science and Technology, Sarajevo, Bosnia and Herzegovina
3 Department for neuroradiology, Clinic for Radiology, Clinical Center University of Sarajevo, Sarajevo, Bosnia and Herzegovina
| Date of Submission | 06-Jun-2020 |
| Date of Acceptance | 10-Aug-2020 |
| Date of Web Publication | 29-Sep-2020 |
Correspondence Address:
Dr. Zijo Begic
Department of Cardiology, Paediatric Clinic, Clinical Center University of Sarajevo, Sarajevo
Bosnia and Herzegovina
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/hm.hm_24_20
Introduction: The head-up tilt table test is noninvasive diagnostic procedure, which is used in the diagnosis of syncope. Syncope presents a benign short-term disorder of cerebral circulation with the sudden loss of consciousness and muscle tone. Aim: The aim is to present not only the role and importance of orthostatic tests in the daily clinical practice of pediatric cardiology, neuropediatrics but also pediatrics in general. Patients and Methods: This study has retrospective descriptive character and included the period from April 1997 to June 2020, during which the registration and analysis of orthostatic stability tests (head-up/tilt table test, tilt table test) was performed. Medical documentation of outpatient and hospitalized patients on the Paediatric Clinic of Clinical Center University of Sarajevo (Register of Tilt Table Test) was used. Results: During this period, 1029 tests were registered and analyzed. Modification test (head-up) was performed in 132 (12.8%) patients, and since 2008, classic tilt table test was performed in 897 (87.1%) patients. Patients were 6.5–19 years old, with a predominance of female patients 611 (59.4%). There were 519 (50.4%) patients who were 15–19 years old and 510 (49.6%) patients who were under 15 years of age. Indications were syncope or suspected syncope in 671 (65.2%) patients, cardiovascular etiology (arrhythmias, chest pain, congenital heart defects [CHDs], surgically corrected CHDs, hypotension, and hypertension) in 195 (19%) patients, neuropediatric pathology (epilepsia, suspected epilepsia, headache, vertigo) in 101 (9.8%) patients, and other indications in 62 (6.03%) patients. From the total number of tests, 862 were first tests (83.4%) and 167 were control tests (16.3%). The positive test was found in 538 (52.3%) patients, most often vasovagal syncope (473 patients or 87.9%). Conclusion: Tilt table test is a reliable diagnostic tool in examining the etiology of syncope, primarily vasovagal, and is an extremely important method primarily in cardiopediatric and neuropediatric daily diagnostics.
Keywords: Pediatrics, syncope, tilt-table test
How to cite this article:
Begic Z, Begic N, Begic E, Spahovic N. The role and importance of the tilt table test in pediatrics: Single-center experience and review of literature. Heart Mind 2020;4:75-9 |
How to cite this URL:
Begic Z, Begic N, Begic E, Spahovic N. The role and importance of the tilt table test in pediatrics: Single-center experience and review of literature. Heart Mind [serial online] 2020 [cited 2023 Mar 29];4:75-9. Available from: http://www.heartmindjournal.org/text.asp?2020/4/3/75/296562 |
| Introduction | |  |
Syncope is a sudden, transitory loss of consciousness and muscle tone and it is the result of cerebral hypoperfusion.[1] Recovery is spontaneous, fast, and complete.[2] It usually lasts 30–60 s, up to a maximum of 5 min.[2] In adulthood, it is most often a symptom of a disease that results in a decrease in cerebral flow. In children, fortunately, it is a benign condition in general. It occurs most often in adolescence, and it is rare in patients below the age of 7. Around 40% of people faint during their lives, half of whom faint during adolescence and the peak age for the first faint is 15 years.[3] In everyday pediatric cardiology practice, syncope is divided to circulatory (cardial and extracardial), metabolic and neurogenic, and psychogenic.[1],[4] Internists divide all syncope into noncardiac, cardiac, and syncope of unclear cause.[5] Clinically, in pediatric practice, we also use the classification of syncope to neurogenic (vasovagal), orthostatic, cardiogenic (arrhythmias and heart defects), other (psychogenic and metabolic), and syncope of unknown cause.[1],[6] Unfortunately, the etiology and mechanism of occurrence of syncope often do not correlate with each other (same cause different mechanisms of occurrence, same mechanism different causes of occurrence). Evaluation of syncope depends on the recognized or suspected type of syncope, which then seeks direction, often through sophisticated methods. In fact, due to the difficult standardization of the diagnostic and therapeutic algorithm, and even with interactive software, there are no fully adequate and standard protocols.
This makes it difficult to have a universal attitude of admission, diagnostics, and therapy, especially if the economic aspect of hospitalization and additional diagnostics and treatment is taken into account. Syncope is an everyday reason for patients' admission and requires the experience and knowledge of primarily pediatric cardiologists and neuropediatricians. Every syncope could also be observed through the evolution of a possible clinical picture. Risk factors for syncope are primarily the underlying causes of orthostatic hypotension.[3] Diagnostic procedures for syncope are standard procedures (history, physical examination, and basic laboratory diagnostics). Every patient with syncope requires detailed measurement of pulse, oxygenation, tension, body weight and height, detailed physical examination, with special emphasis on the pediatric cardiological and neuropediatric clinical aspect. Diagnostic tests we use in the daily treatment of patients with syncope are electrocardiography (ECG), pulse oximetry, blood tests, measurement of orthostatic vitality, echocardiography, ergometry, tilt table test, electrophysiology, electroencephalography, audiovestibulogram and color Doppler of neck vessels, computed tomography, magnetic resonance imaging, and transcranial color Doppler.[7],[8],[9] Attention should certainly be paid to conditions that may look like syncope: migraine, acute hypoxia, hyperventilation, acute intoxication (drugs, narcotics, alcohol), epileptic seizures, hypoglycemia, bilateral carotid artery dissection, and psychogenic syncope.[10],[11],[12]
The treatment of syncope is education (prevention of events leading to syncope and recognition of presyncopal symptoms with self-help maneuvers to prevent syncope, lifestyle modification) and implementation of general measures; avoidance of triggers (long-standing, crowds, warm environment, fluid loss, etc.,), recognition of prodromal symptoms, prevention of syncope (isometric exercises, sufficient fluid and salt intake, volume expanders, drinks (primarily carbonated), moderate load exercises and exercises tilt or so-called tilt exercises, endurance exercises, orthostatic training) and pharmacotherapy (beta-blockers, alpha agonists, selective serotonin blockers, fludrocortisone, mineralocorticoids).[7],[13],[14],[15] Presyncope is a milder form of syncope (fainting, emptiness in the head, general weakness, temporary loss of hearing and vision), but without the loss of consciousness.[16] Syncope and other disorders of consciousness are sometimes difficult to distinguish due to the often unique pathophysiology of transient global cerebral hypoperfusion caused by low peripheral resistance and/or decreased cardiac output, with consequent loss of consciousness and postural control. The prevention of syncope includes the prevention of injuries during syncope and the potential danger of critical activity, with the necessity of self-limitation by patients and parents, but also the legal legislation of social communities. Often, the approach to a patient with syncope must be individualized. Every diagnosis and cause of syncope must begin with a detailed history, physical examination, simple laboratory tests, and an ECG.[7]
The tilt table test is a noninvasive diagnostic procedure used in pediatrics. It has been used since 1986, along with other orthostatic tests with minor additions and modernization.[17],[18],[19] It is technically a simple test and with good conditions, adequate patient preparation, written consent of parents, oxygen support and with available resuscitation equipment and a defibrillator, it is very comfortable and safe.[17],[18] Pulse, heart rate, continuous ECG Holter recording, and blood pressure are monitored continuously during the test. We need at least 60–90 min for the adequate test.[17],[18],[19],[20] The result can be normal or negative, and we have small fluctuations in systolic and diastolic blood pressure as well as pulse with a regular ECG.[17] A positive response is characterized by the loss of consciousness with changes in blood pressure, pulse, and occurrence of cardiac arrhythmias. Symptoms that precede loss of consciousness during the examination are pallor, nausea, sweating, palpitations, dizziness, and lightheadedness. It is indisputable in the diagnosis of vasovagal syncope, but it is also good for the differential diagnosis of epilepsy and syncope. Complications during the test are rare, mostly mild arrhythmias, but also possible ventricular fibrillation and asystole.[17],[18],[19],[20] The presence of a pediatric cardiologist and an educated nurse is mandatory when performing the test. Contraindications for the test are critical aortic or mitral stenosis left ventricular outflow tract obstruction, and proximal coronary artery stenosis as well as critical cerebrovascular stenosis.[18],[20],[21] The test differentiates vasovagal syncope (type I mixed, type IIa cardioinhibitory without asystole, type IIb cardioinhibitory with asystole, type III vasodepressor, except for chronotropic incompetence and excessive increase in heart rate), carotid sinus hypersensitivity, and postural orthostatic syndrome (orthostatic intolerance).[21] It is often used together with ergometry, and echocardiography and complete ECG must be done before the test.
Aim
The aim of the article was to present not only the role and importance of orthostatic tests in the daily clinical practice of pediatric cardiology, neuropediatrics but also pediatrics in general.
| Patients and Methods | | |
The article has retrospective and descriptive character of the research and included the period April 1997–June 2020 during which the registration and analysis of orthostatic stability tests (head-up/tilt table test, tilt table test) were done. Medical documentation of outpatient and hospitalized patients on the Pediatric Clinic of Clinical Center University of Sarajevo (Register of Tilt Table Test) was used.
| Results | | |
During this period, 1029 tests were registered and analyzed. Modification test (head-up) was performed in 132 (12.8%) patients, and since 2008 classic tilt table test was performed in 897 (87.1%) patients. Patients were 6.5–19 years old, with a predominance of female patients 611 (59.4%). There were 519 (50.4%) patients that were 15–19 years old and 510 (49.6%) patients who were under 15 years of age. Indications were syncope or suspected syncope in 671 (65.2%) patients, cardiovascular etiology (arrhythmias, chest pain, congenital heart defects [CHD], surgically corrected CHDs, hypotension, and hypertension) in 195 (19%) patients, neuropediatric pathology (epilepsia, suspected epilepsia, headache, vertigo) in 101 (9.8%) patients, and other indications in 62 (6.03%) patients [Table 1]. From the total number of tests, 862 were the first tests (83.4%), and 167 were control tests (16.3%).
The positive test was found in 538 (52.3%) patients, most often vasovagal syncope (473 patients or 87.9%), whereas 12.1% was due to other kinds of syncope-orthostatic, cardiogenic (arrhythmias and heart defects), other (psychogenic and metabolic), and syncope of unknown cause.
| Discussion | | |
After more than 1000 done head-up tilt table tests with positive evaluation for syncope >50%, a lot of doubts remain. As a rule, short-term syncopal attacks without other accompanying symptoms are not of great medical importance. The causes of such syncope, especially if they occur in peace, suggest a good condition and a good prognosis. The most common syncopes are reflex syncopes, which include vasovagal (vasodepressor) syncope, situational, sinus carotid syncope, and atypical tilt-positive syncope.
Head-up tilt table test is used to confirm the suspicion on neurocardiogenic syncope in patients who have classical anamnesis about vasovagal-vasodepresorry syncope.
The aim of a tilt table test is to preproduce and objectify the patient's symptoms through orthostatic stress. Headache can be a symptom of neurocardiogenic syncope, along with other symptoms. Furthemore, headache can indicate existence of hypertension and even hypotension. Headache can be a symptom of uncontrolled hypertension. Headache is a very nonspecific symptom, but in certain patients, based on individual approach, it could be an indication for cardiological, especially when another etiology is excluded.
The tilt table test is positive if clinically clear symptoms of presyncope or syncope can be provoked. The tilt table test is useful as a diagnostic tool if the patient's symptoms during the test correspond to the symptoms during previous syncopes. Asymptomatic fluctuations in blood pressure and pulse during the test are not relevant.
Vasovagal syncope is a disease of younger people, it occurs due to physiological stress or injury and it is generally benign. As a rule, it occurs when extracting blood, teeth, in crowded places, in places with high humidity and heat, or in extremely cold places, especially during standing or sudden getting up. It is caused by a reflex drop in blood pressure due to insufficiently adapted baro and mechanoreceptors in the heart and large blood vessels (aorta and carotid arteries). As soon as the person reaches a horizontal position, normal cerebrovascular flow is established and the symptoms cease. Presyncopes in the form of vasovagal reactions such as nausea, headache, cold sweats, and slowing of the pulse are usually heard from patients after syncope and this is actually what is defined in everyday practice that “the patient got sick” or was an introduction to syncope. This could be used for future recognition of these symptoms and the prevention of syncope. Pathophysiologically, there is a decrease in the tone of the peripheral circulation and redistribution of blood to the periphery (veins) at the expense of reducing the stroke volume of the heart and reducing cerebrovascular flow. Vasodilatation is the dominant hypotensive mechanism. The mechanism for recovery is more likely the effect of increased venous return on stroke volume (Frank – Starling relationship) than the reversal of the cardioinhibitory effect.[22] Since syncope repeats in many younger people, which can be seen from the data of control tilt table tests, it is assumed that there is constitutional vagotonia in them with a sudden decrease of sympathetic-adrenergic vasoconstrictor activity of the body. During the tilt table test, first tachycardia is registered, and then a jump in pressure due to a temporary increase in sympathetic tone, and then there is sudden hypotension and bradycardia, even possible asystole due to the effect on the vagus nerve. It is interesting to mention that this test can be false positive in which tilt-induced fainting occurs in the absence of real-world fainting.[23] The first step in the treatment of neurocardiogenic syncope includes general measures, such as avoidance of triggers such as prolonged standing, loss of intravascular volume, crowd, and warm environment. An increased salt intake (“volume expander”) should be recommended. If general measures are not successful, pharmacological approaches are available. However, it should be noted that the data are insufficient regarding pharmacological therapy. There are generally no valid recommendations. The following drugs can be used in childhood and adolescence: beta-blockers block excessive activation of the sympathetic nervous system (metoprolol), mineralocorticoids lead to increased intravascular volume (fludrocortisone), alpha 1 agonists lead to vasoconstriction (midodrine), serotonin antagonists since there is an evidence for central serotonergic components in the genesis of syncope (fluoxetine).[7],[20],[21] The prognosis of the vasovagal syncope is very good. In the vast majority of cases in adolescent patients, syncope stops within a few years at most. It is necessary, however, to distinguish whether it is neurocardiogenic or cardiogenic syncope that has higher mortality if left untreated. It does not have to be significant, but the possibility of associated significant morbidity (injuries, falls, traffic accidents), as well as potential dangers if syncope occurs during a certain activity (sports, driving, operating heavy machines, during operations, etc.,) must also be taken into account. The most important thing is to exclude the danger to life and make a quick assessment of the possible cause and significance.
Orthostatic hypotension is the most common after vasovagal syncope and occurs due to disorders of the autonomic regulation of the sympathetic-adrenergic system.[24] In people with this syncope after sudden getting up, decrease in blood pressure, fainting, visual and hearing impairment, and weakness and instability occur. It would be normal that an increase in peripheral vascular resistance and an acceleration of the heart rate occur, but this does not happen, and due to many reasons, there is a loss of consciousness and postural tone.[25] A special form of this type of syncope is idiopathic orthostatic hypotension (dysfunction of the autonomic nervous system).[26] In children, micturition syncope, defecation syncope, syncope due to swallowing, so-called cough syncope, syncope due to physical activity or alcoholism, drugs, medications are rare.[6] When hiking to high altitudes, syncope can also occur, and also during traveling in airplanes, deep diving, and even due to fear.
Metabolic syncopes are mainly seen in people with diabetes with prodromal symptoms (weakness, sweating, shivering, confusion, tachycardia), and usually they occur during the administration of insulin or due to hypoglycemia when the patients have poorly regulated eating habits.[27] They are also found in hyperventilation syndrome, but also in conditions of hypoxia and acidosis.[28]
Neuropsychogenic conditions or syncopes related to cerebrovascular diseases are also encountered in our indications for the tilt table test in 10% of all cases. The most common causes related to the central nervous system are epilepsy of the temporal lobe, and ischemia of the vertebrobasilar arterial system, but also diseases of the carotid arteries. In subclavian steal syndrome, vertigo, migraine, and glossopharyngeal as well as trigeminal neuralgia are part of the clinical symptomatology.[29] They are found in brain tumors, and can often be an expression of anxiety disorders too.[29] Prodromal symptoms related to cerebral events are diplopia or dizziness, dysarthria, dysphagia, hearing disorders, vertigo, ataxia, weakness/hypoesthesia of the limbs, and pain/hypoesthesia of the face.[29],[30]
Sudden syncope in patients who have not had a change in body position and prodromal symptoms, as well as patients with previously proven congenital or surgically corrected CHDs, abnormal ECG and the appearance of physical exertion, requires additional caution.[6],[7] Cardiogenic (cardiovascular) causes of syncope in our study were present in almost a fifth of cases (20%). In adulthood, the percentage of cardiogenic syncope is up to 25%. Today, in everyday work, more and more importance is given to syncopes of unclear cause, which usually require complete pediatric cardiology diagnostics. The treatment of cardiovascular syncope is a highly responsible and complex task.
It is believed that the cardiac causes of syncope are mainly related to arrhythmia, but also the cause can be obstructive lesions of the left and right heart or myocardial dysfunction.[7],[31] The mechanism of cardiac syncope is reduced cardiac ejection and consequently reduced cerebral blood flow.[7] Cardiac causes of syncope are not as harmless as vasovagal syncope and require complete pediatric cardiology diagnostics.
Syncope in obstructive heart lesions is usually provoked by physical activity. So-called arrhythmogenic syncopes (ventricular and supraventricular tachycardias, blocks, Wolff-Parkinson-White syndromes, long QT intervals, sick-sinus syndromes, Brugada syndrome and occasionally in implanted pacemakers) are the diagnosis that are occasionally encountered.[30] Syncope associated with myocardial dysfunction and ischemia is rare in children (Kawasaki disease, blood vessel abnormalities, cardiomyopathy). Incisional arrhythmias, which sometimes occur after surgical correction of congenital heart anomalies, are also a special problem.[19],[27],[31],[32] There is an impression that the number of syncopes related to rhythm disorders could be even higher in everyday work in future due to the development of pediatric cardiology/cardiosurgery.
In the introduction, the importance of anamnesis (possible previously unrecognized congenital heart anomalies), sudden death in the family, prodromal symptoms, the fact that syncope was preceded by physical activity, the duration of syncope, the presence of arrhythmias was emphasized. The physical examination must be complete with good documentation of heart rate, blood pressure, saturation, and careful palpation of pulses with the determination of pulse quality and rhythm, but also careful auscultation. In cardiogenic syncope, it is mandatory to verify prodromal symptoms lasting longer than 10 s (dark vision, swaying, nausea, sweating, numbness of the face and lower extremities, but also previous chest pain, abdominal pain, back pain, headache, presyncopal dyspnea).[32],[33],[34] Laboratory testing, ECG, and especially continuous ECG Holter monitoring and head-up tilt table testing are required. In recent decades, attempts have been made to standardize the diagnostic and therapeutic algorithm for syncope, which unfortunately did not meet expectations.[33],[34] Diagnostic and therapeutic guidelines for syncope should be carefully incorporated into daily work. Additional diagnostic procedures such as cardiac electrophysiology for cardiac arrhythmias and highly sophisticated angiographic methods should also be considered. It should be noted that cardiac causes, whether it is arrhythmias or other cardiovascular diseases, have significantly (up to 20 times) higher mortality compared to mortality due to other causes. Neuropediatric diagnostics should exclude events in the central nervous system, primarily convulsions, and also migraines, as well as incidents with bleeding blood vessels. Mortality due to syncope in childhood is insignificant, but in at least a third of cases, mortality is caused by arrhythmias and/or cardiovascular diseases.
| Conclusion | | |
Syncope is one of the pediatric emergency conditions which can have a serious influence on the quality of life. Syncope in the pediatric age is still in the gap of acquired knowledge and practical treatment. Cardiogenic syncope, as well as neuropsychogenic, is of special importance due to possible vital threat, and even sudden death. Patient education is a fundamental part above all. The decision on hospitalization, diagnosis, and treatment should be the primary responsibility of the pediatric cardiologist and neuropediatrician (preferably both).
Moreover, all pediatricians should have a good knowledge considering vasovagal syncope. In fact, every child with syncope requires pediatric cardiology diagnostics and a tilt table test. Tilt table test is reliable in examining the unclear etiology of syncope, and despite the low specificity and sensitivity as well as inconsistent protocol, it is an extremely important method primarily in pediatric cardiology and neuropediatric everyday diagnostics.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
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[Table 1]
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