Vasovagal syncope(VVS),which is triggered by physical exertion,is typically observed in athletes or patients with structural heart disease.There have been few reported cases among sedentary individuals.This case repor...Vasovagal syncope(VVS),which is triggered by physical exertion,is typically observed in athletes or patients with structural heart disease.There have been few reported cases among sedentary individuals.This case report details the experience of a 42-year-old sedentary woman who fainted during a treadmill stress test.Despite the absence of abnormalities in baseline cardiac and neurological evaluations,the patient exhibited sinus arrest(lasting 5–12 seconds)with significant ST-segment depression during haemodynamic collapse.Comprehensive assessments,incorporating coronary angiography,echocardiography,cranial computed tomography(CT),and biochemical testing,excluded the presence of structural or ischemic heart disease,arrhythmogenic syndromes,and cerebrovascular disorders.A Calgary Syncope Symptom Score of 3 confirmed the diagnosis of VVS,a diagnosis that was further substantiated by the patient’s symptoms resolving spontaneously when she was positioned supine.This case demonstrates that exercise-induced syncope can occur in individuals who are physically unfit and have no cardiac abnormalities.Transient ST-segment changes in such cases reflect autonomic nervous system dysfunction rather than myocardial ischaemia.It is incumbent upon clinicians to consider a neurocardiogenic mechanism in sedentary patients presenting with exertional syncope despite a negative standard cardiac evaluation.展开更多
The purpose of the present paper is to explore Edgar Lawrence Doctorow’s novel Ragtime(1975)as a masterful adaptation of musical form in fiction.It demonstrates the ways in which the use of musical devices of Ragtime...The purpose of the present paper is to explore Edgar Lawrence Doctorow’s novel Ragtime(1975)as a masterful adaptation of musical form in fiction.It demonstrates the ways in which the use of musical devices of Ragtime shapes the rhythmic/narrative structure of the novel.The article offers the reading of the novel as a musicalized fiction,or,in other words,as a form of musico-literary intermediality.It focuses on the chief characteristics of Doctorow’s novel such as a plurality of independent consciousnesses and a diversity of simultaneous points of view/voices.The novel by its very design is polyphonic.Manipulating polyrhythmic effects,mixed rhythms,repetitive phrases and leitmotifs,Doctorow is experimenting with the rhythm both on micro and macro textual levels.展开更多
Vasovagal syncope(VVS) and postural tachycardia syndrome(POTS) are the main forms of orthostatic intolerance in pediatrics and both are underlying causes of neurally-mediated syncope.In recent years,increasing attenti...Vasovagal syncope(VVS) and postural tachycardia syndrome(POTS) are the main forms of orthostatic intolerance in pediatrics and both are underlying causes of neurally-mediated syncope.In recent years,increasing attention has been paid to the management of VVS and POTS in children and adolescents.A number of potential mechanisms are involved in their pathophysiology,but the leading cause of symptoms varies among patients.A few studies thus have focused on the individualized treatment of VVS or POTS based on selected hemodynamic parameters or biomarkers that can predict the therapeutic effect of certain therapies and improve their effectiveness.This review summarizes the latest developments in individualized treatment of VVS and POTS in children and indicates directions for further research in this field.展开更多
Syncope is defined as a transient loss of consciousness due to global cerebral hypoperfusion, accompanied by loss of muscle tone and failure to maintain an active position. Vasovagal syncope (VVS) is the most common p...Syncope is defined as a transient loss of consciousness due to global cerebral hypoperfusion, accompanied by loss of muscle tone and failure to maintain an active position. Vasovagal syncope (VVS) is the most common presentation of syncope, and its diagnostic criteria include:(1) absence of any other evident etiology for syncope or presyncope,(2) positive response to head-up tilt test with evident vasovagal reaction (hypotension and/or bradycardia), and (3) no concomitant chronic or acute disease [1, 2]. The onset of VVS peaks initially in childhood and adolescence, and accounts for 60%–70% of all syncopal cases. Clinicians pay great attention to syncope among children and adolescents, due to its high prevalence and its impact on patients’ quality of life. Affected individuals often experience mental stress, economic burdens, and accidental bodily injuries related to syncope [2]. While the pathogenesis of VVS is not fully understood, autonomic nervous dysfunction has been identified as a contributing mechanism. The examination of autonomic nervous function can provide important information about patients with syncope.展开更多
Vasovagal syncope is a common cause of recurrent syncope. Clinically, these episodes may present as an isolated event with an identifiable trigger, or manifest as a cluster of recurrent episodes warranting intensive e...Vasovagal syncope is a common cause of recurrent syncope. Clinically, these episodes may present as an isolated event with an identifiable trigger, or manifest as a cluster of recurrent episodes warranting intensive evaluation. The mechanism of vasovagal syncope is incompletely understood. Diagnostic tools such as implantable loop recorders may facilitate the identification of patients with arrhythmia mimicking benign vasovagal syncope. This review focuses on the management of vasovagal syncope and discusses the non-pharmacological and pharmacological treatment options, especially the use of midodrine and selective serotonin reuptake inhibitors. The role of cardiac pacing may be meaningful for a subgroup of patients who manifest severe bradycardia or asystole but this still remains controversial.展开更多
This study was to investigate the changes of autonomic nerve function and hemodynamics in patients with vasovagal syncope(VVS) during head-up tilt-table testing(HUT). HUT was performed in 68 patients with unexplained ...This study was to investigate the changes of autonomic nerve function and hemodynamics in patients with vasovagal syncope(VVS) during head-up tilt-table testing(HUT). HUT was performed in 68 patients with unexplained syncope and 18 healthy subjects served as control group. According to whether bradycardia, hypotension or both took place during the onset of syncope, the patients were divided during the test into three subgroups: vasodepressor syncope(VD), cardioinhibitory syncope(CI) and mixed syncope(MX) subgroups. Heart rate, blood pressure, heart rate variability(HRV), and deceleration capacity(DC) were continuously analyzed during HUT. For all the subjects with positive responses, the normalized low frequency(LFn) and the LF/HF ratio markedly decreased whereas normalized high frequency(HFn) increased when syncope occurred. Syncopal period also caused more significant increase in the power of the DC in positive groups. These changes were more exaggerated compared to controls. All the patients were indicative of a sympathetic surge in the presence of withdrawal vagal activity before syncope and a sympathetic inhibition with a vagal predominance at the syncopal stage by the frequency-domain analysis of HRV. With the measurements of DC, a decreased vagal tone before syncope stage and a vagal activation at the syncopal stage were observed. The vagal tone was higher in subjects showing cardioinhibitory responses at the syncopal stage. DC may provide an alternative method to understand the autonomic profile of VVS patients.展开更多
Postural orthostatic tachycardia syndrome （POTS） has been recognized since at least 1940.A review of the literature identifies differences in the definition for this condition and wide variations in treatment and ou...Postural orthostatic tachycardia syndrome （POTS） has been recognized since at least 1940.A review of the literature identifies differences in the definition for this condition and wide variations in treatment and outcomes.This syndrome appears to describe a group of conditions with differing pathophysiology,which requires treatment tailored to the true underlying disorder.Patients need to be fully evaluated to guide treatment.Further research is required to effectively classify the range of underlying pathophysioiogy that can produce this syndrome and to guide optimal management.展开更多
There is increasing awareness among the cardiology community regarding ictal bradyarrhythmias as a cause of loss of consciousness. A high degree of suspicion is necessary when diagnosing ictal bradyarrhythmias, and de...There is increasing awareness among the cardiology community regarding ictal bradyarrhythmias as a cause of loss of consciousness. A high degree of suspicion is necessary when diagnosing ictal bradyarrhythmias, and delay in diagnosing this condition may lead to morbidity associated with falls and trauma. Ictal bradyarrhythmias have also been suggested to be associated with sudden unexplained death in epilepsy, although evidence related to this association is limited. There is no guidelinedirected therapy for symptomatic ictal bradyarrhythmias due to a lack of randomized, controlled trials. Cardiac pacemaker therapy is commonly used for these patients; however, currently, there is no universal agreement on the pacing indications for these patients. In this review, we focus on the pathophysiology and clinical presentation of ictal bradyarrhythmias and then discuss the pacing need based on the available literature data.展开更多
Objective: To evaluate the serious response during tilt-table test (TTT) and its prophylactic management. Method: Seventy-six elderly patients were tested at a tilt angle of 70 degrees for a maximum of 45 min and then...Objective: To evaluate the serious response during tilt-table test (TTT) and its prophylactic management. Method: Seventy-six elderly patients were tested at a tilt angle of 70 degrees for a maximum of 45 min and then subjected to isoprotere- nol-provocative tilt testing. ECG and blood pressure were monitored during the test and patients were kept at normal saline con- dition through a peripheral intravenous duct. Results: Fifty-one of 76 patients were defined as positive including 23 having serious response; 6 of the 23 patients had arteriosclerosis involving internal carotid arteries and 7 cases had bradycardia, two of which were associated with II°-I A-V block and the others with chronic atrial fibrillation. The serious response consisted of cardiac arrest for more than 5 s (6 cases), or serious bradycardia for more than 1 min (7 cases) or serious hypotension for more than 1 min (10 cases). Those with serious response were managed by returning to supine position, thus driving up legs and intravenous atropine, CPR (2 cases with cardiac arrest) and needing oxygen supplementation (11 cases). Only 2 hypotension patients recovered gradually by 10 min after emergency management, while others recovered rapidly with no complications. Conclusion: Although non-invasive, TTT may result in serious response, especially in elderly. Therefore proper patient selection, control of isoproterenol infusion and close observation of vital signs are decisive for a safe consequence.展开更多
文摘Vasovagal syncope(VVS),which is triggered by physical exertion,is typically observed in athletes or patients with structural heart disease.There have been few reported cases among sedentary individuals.This case report details the experience of a 42-year-old sedentary woman who fainted during a treadmill stress test.Despite the absence of abnormalities in baseline cardiac and neurological evaluations,the patient exhibited sinus arrest(lasting 5–12 seconds)with significant ST-segment depression during haemodynamic collapse.Comprehensive assessments,incorporating coronary angiography,echocardiography,cranial computed tomography(CT),and biochemical testing,excluded the presence of structural or ischemic heart disease,arrhythmogenic syndromes,and cerebrovascular disorders.A Calgary Syncope Symptom Score of 3 confirmed the diagnosis of VVS,a diagnosis that was further substantiated by the patient’s symptoms resolving spontaneously when she was positioned supine.This case demonstrates that exercise-induced syncope can occur in individuals who are physically unfit and have no cardiac abnormalities.Transient ST-segment changes in such cases reflect autonomic nervous system dysfunction rather than myocardial ischaemia.It is incumbent upon clinicians to consider a neurocardiogenic mechanism in sedentary patients presenting with exertional syncope despite a negative standard cardiac evaluation.
文摘The purpose of the present paper is to explore Edgar Lawrence Doctorow’s novel Ragtime(1975)as a masterful adaptation of musical form in fiction.It demonstrates the ways in which the use of musical devices of Ragtime shapes the rhythmic/narrative structure of the novel.The article offers the reading of the novel as a musicalized fiction,or,in other words,as a form of musico-literary intermediality.It focuses on the chief characteristics of Doctorow’s novel such as a plurality of independent consciousnesses and a diversity of simultaneous points of view/voices.The novel by its very design is polyphonic.Manipulating polyrhythmic effects,mixed rhythms,repetitive phrases and leitmotifs,Doctorow is experimenting with the rhythm both on micro and macro textual levels.
基金supported by Peking University Clinical Scientist Program (BMU2019LCKXJ001,Beijing)Fundamental Research Funds for the Central Universities of China.
文摘Vasovagal syncope(VVS) and postural tachycardia syndrome(POTS) are the main forms of orthostatic intolerance in pediatrics and both are underlying causes of neurally-mediated syncope.In recent years,increasing attention has been paid to the management of VVS and POTS in children and adolescents.A number of potential mechanisms are involved in their pathophysiology,but the leading cause of symptoms varies among patients.A few studies thus have focused on the individualized treatment of VVS or POTS based on selected hemodynamic parameters or biomarkers that can predict the therapeutic effect of certain therapies and improve their effectiveness.This review summarizes the latest developments in individualized treatment of VVS and POTS in children and indicates directions for further research in this field.
基金supported by the Science and Technology Program of Beijing Municipality, China (Z171100001017253)Peking University Clinical Scientist Program, China (BMU2019LCKXJ001)
文摘Syncope is defined as a transient loss of consciousness due to global cerebral hypoperfusion, accompanied by loss of muscle tone and failure to maintain an active position. Vasovagal syncope (VVS) is the most common presentation of syncope, and its diagnostic criteria include:(1) absence of any other evident etiology for syncope or presyncope,(2) positive response to head-up tilt test with evident vasovagal reaction (hypotension and/or bradycardia), and (3) no concomitant chronic or acute disease [1, 2]. The onset of VVS peaks initially in childhood and adolescence, and accounts for 60%–70% of all syncopal cases. Clinicians pay great attention to syncope among children and adolescents, due to its high prevalence and its impact on patients’ quality of life. Affected individuals often experience mental stress, economic burdens, and accidental bodily injuries related to syncope [2]. While the pathogenesis of VVS is not fully understood, autonomic nervous dysfunction has been identified as a contributing mechanism. The examination of autonomic nervous function can provide important information about patients with syncope.
文摘Vasovagal syncope is a common cause of recurrent syncope. Clinically, these episodes may present as an isolated event with an identifiable trigger, or manifest as a cluster of recurrent episodes warranting intensive evaluation. The mechanism of vasovagal syncope is incompletely understood. Diagnostic tools such as implantable loop recorders may facilitate the identification of patients with arrhythmia mimicking benign vasovagal syncope. This review focuses on the management of vasovagal syncope and discusses the non-pharmacological and pharmacological treatment options, especially the use of midodrine and selective serotonin reuptake inhibitors. The role of cardiac pacing may be meaningful for a subgroup of patients who manifest severe bradycardia or asystole but this still remains controversial.
基金supported by a grant from the Wuhan Science and Technology Program of China(No.2014060101010032)
文摘This study was to investigate the changes of autonomic nerve function and hemodynamics in patients with vasovagal syncope(VVS) during head-up tilt-table testing(HUT). HUT was performed in 68 patients with unexplained syncope and 18 healthy subjects served as control group. According to whether bradycardia, hypotension or both took place during the onset of syncope, the patients were divided during the test into three subgroups: vasodepressor syncope(VD), cardioinhibitory syncope(CI) and mixed syncope(MX) subgroups. Heart rate, blood pressure, heart rate variability(HRV), and deceleration capacity(DC) were continuously analyzed during HUT. For all the subjects with positive responses, the normalized low frequency(LFn) and the LF/HF ratio markedly decreased whereas normalized high frequency(HFn) increased when syncope occurred. Syncopal period also caused more significant increase in the power of the DC in positive groups. These changes were more exaggerated compared to controls. All the patients were indicative of a sympathetic surge in the presence of withdrawal vagal activity before syncope and a sympathetic inhibition with a vagal predominance at the syncopal stage by the frequency-domain analysis of HRV. With the measurements of DC, a decreased vagal tone before syncope stage and a vagal activation at the syncopal stage were observed. The vagal tone was higher in subjects showing cardioinhibitory responses at the syncopal stage. DC may provide an alternative method to understand the autonomic profile of VVS patients.
文摘Postural orthostatic tachycardia syndrome （POTS） has been recognized since at least 1940.A review of the literature identifies differences in the definition for this condition and wide variations in treatment and outcomes.This syndrome appears to describe a group of conditions with differing pathophysiology,which requires treatment tailored to the true underlying disorder.Patients need to be fully evaluated to guide treatment.Further research is required to effectively classify the range of underlying pathophysioiogy that can produce this syndrome and to guide optimal management.
文摘There is increasing awareness among the cardiology community regarding ictal bradyarrhythmias as a cause of loss of consciousness. A high degree of suspicion is necessary when diagnosing ictal bradyarrhythmias, and delay in diagnosing this condition may lead to morbidity associated with falls and trauma. Ictal bradyarrhythmias have also been suggested to be associated with sudden unexplained death in epilepsy, although evidence related to this association is limited. There is no guidelinedirected therapy for symptomatic ictal bradyarrhythmias due to a lack of randomized, controlled trials. Cardiac pacemaker therapy is commonly used for these patients; however, currently, there is no universal agreement on the pacing indications for these patients. In this review, we focus on the pathophysiology and clinical presentation of ictal bradyarrhythmias and then discuss the pacing need based on the available literature data.
文摘Objective: To evaluate the serious response during tilt-table test (TTT) and its prophylactic management. Method: Seventy-six elderly patients were tested at a tilt angle of 70 degrees for a maximum of 45 min and then subjected to isoprotere- nol-provocative tilt testing. ECG and blood pressure were monitored during the test and patients were kept at normal saline con- dition through a peripheral intravenous duct. Results: Fifty-one of 76 patients were defined as positive including 23 having serious response; 6 of the 23 patients had arteriosclerosis involving internal carotid arteries and 7 cases had bradycardia, two of which were associated with II°-I A-V block and the others with chronic atrial fibrillation. The serious response consisted of cardiac arrest for more than 5 s (6 cases), or serious bradycardia for more than 1 min (7 cases) or serious hypotension for more than 1 min (10 cases). Those with serious response were managed by returning to supine position, thus driving up legs and intravenous atropine, CPR (2 cases with cardiac arrest) and needing oxygen supplementation (11 cases). Only 2 hypotension patients recovered gradually by 10 min after emergency management, while others recovered rapidly with no complications. Conclusion: Although non-invasive, TTT may result in serious response, especially in elderly. Therefore proper patient selection, control of isoproterenol infusion and close observation of vital signs are decisive for a safe consequence.
