Background: Syncope is a relevant health problem in military environments. Reliable diagnosis is challenging. Tilt table testing is an important tool for syncope diagnosis. The aim of this study was to determine wheth...Background: Syncope is a relevant health problem in military environments. Reliable diagnosis is challenging. Tilt table testing is an important tool for syncope diagnosis. The aim of this study was to determine whether signs such as prodromal symptoms, co-morbidity, frequency of syncopal events, body length, body mass index, and electrocardiography(ECG) abnormalities can be used to predict the success of tilt table testing at diagnosing syncope.Methods: Data from 100 patients with histories of syncope or pre-syncope, who were diagnosed using head-up tilt table testing, were retrospectively analyzed in a cross-sectional analysis. The diagnostic procedure was based upon a modified version of the Westminster protocol without any pharmacological provocation. Results: Patients showing pathological reaction patterns during tilt table testing suffered from prodromal symptoms, such as dizziness and sweating, significantly more often. The patients reported more injuries resulting from syncopal events and more previous syncopal events, and the prevalence of co-morbidity was greater among patients presenting negative findings during tilt testing. An asthenic-leptosomal physique was not confirmed as a risk factor for syncopal events as is the case for idiopathic arterial hypotension. However, patients with pathological reaction patterns during tilt table testing were significantly taller. This finding was detected for both females and males. No significant predictors were found in the ECG patterns of patients showing syncope during tilt table testing.Conclusions: Frequency of prior syncope and prodromal symptoms, and increased body length with an otherwise good state of health influence the predictive value of tilt table testing for syncope diagnosis. In particular, if these factors are present, tilt table testing should be considered part of the diagnostic algorithm for soldiers with recurrent syncope.展开更多
Background:Syncope is a relevant health problem in military environments.Reliable diagnosis is challenging.Tilt table testing is an important tool for syncope diagnosis.The aim of this study was to determine whether s...Background:Syncope is a relevant health problem in military environments.Reliable diagnosis is challenging.Tilt table testing is an important tool for syncope diagnosis.The aim of this study was to determine whether signs such as prodromal symptoms,co-morbidity,frequency of syncopal events,body length,body mass index,and electrocardiography abnormalities can be used to predict the success of tilt table testing at diagnosing syncope.Methods:Data from 100 patients with histories of syncope or pre-syncope,who were diagnosed using head-up tilt table testing,were retrospectively analyzed in a cross-sectional analysis.The diagnostic procedure was based upon a modified version of the Westminster protocol without any pharmacological provocation.Results:Patients showing pathological reaction patterns during tilt table testing suffered from prodromal symptoms,such as dizziness and sweating,significantly more often.The patients reported more injuries resulting from syncopal events and more previous syncopal events,and the prevalence of co-morbidity was greater among patients presenting negative findings during tilt testing.An asthenic-leptosomal physique was not confirmed as a risk factor for syncopal events as is the case for idiopathic arterial hypotension.However,patients with pathological reaction patterns during tilt table testing were significantly taller.This finding was detected for both females and males.No significant predictors were found in the electrocardiogram patterns of patients showing syncope during tilt table testing.Conclusions:Frequency of prior syncope and prodromal symptoms,and increased body length with an otherwise good state of health influence the predictive value of tilt table testing for syncope diagnosis.In particular,if these factors are present,tilt table testing should be considered part of the diagnostic algorithm for soldiers with recurrent syncope.展开更多
To study the role of autonomic nervous system in the period of developing syncope induced by head-up tilt test(HUT), we analysed the changes of heart rate power spectral density(HRPSD) in 50 patients with unexplained ...To study the role of autonomic nervous system in the period of developing syncope induced by head-up tilt test(HUT), we analysed the changes of heart rate power spectral density(HRPSD) in 50 patients with unexplained syncope, including 15 positive patients (Group 1) and 35 negative patients(Group 2), and 15 negative healthy persons(Group 3) in 5 minute periods before and after tilting and 5 minutes before the end of test. HRPSD and their changes in total(T), very low-frequence(VLF), low-frequence(LF), high-frequence(HF) and the ratio of low/high frequence(LF/HF) were similar (P>0.05) 5 minutes before and after tilting among three groups. Five minutes before the end of test, Group 1 had obvious increase of T, VLF, LF and LF/HF while Group 2 and 3 had not such significant changes. There was significant difference(P<0.01) compared Group 1 with Group 2, 3. The results showed that the abnormal regulatory function of autonomic nervous system played an important role in the mechanism of symcope induced by HUT, the positive group had abnormal increase of sympathetic tone and imbalance of sympathetic/parasympathetic neural tone before syncope appeared.展开更多
The cardio-ankle vascular index (CAVI) is a new index of arterial stiffness that can be measured with a VaSera VS-1000 device. An association between certain arterial stiffness indices and cardiac function has been fo...The cardio-ankle vascular index (CAVI) is a new index of arterial stiffness that can be measured with a VaSera VS-1000 device. An association between certain arterial stiffness indices and cardiac function has been found but has not yet been validated. The aim of this study was to establish whether any significant relationship exists between cardiac index (CI) and CAVI. Twenty healthy male volunteers with a mean age of 30 ± 5 years and a mean BMI of 23.1 ± 1.1 kg/m2 participated in the study. CO was estimated using a Doppler technique, and CAVI was measured with a VaSeraVS-1000 device. A motorised tilting table was used to achieve head-up tilt (HUT) angles of 0°, 30°and 60°, to modify the peripheral sympathetic outflow. We found that there was a significant inverse correlation between CI and the degree of head-up tilt, ( for 0°and 30°;for 0° and 60°, p for both;for 30° and 60°, ). CAVI showed a significant positive correlation relative with the degree of HUT, ( for 0° and 30°;for 0° and 60°;for 30° and 60°, for all). A significant negative correlation was found between CI and CAVI r = - 0.47, p Additionally, a significant p increase in PVR values was observed for increasing HUT values. In conclusion: An inverse relationship between CI and CAVI was shown;a decrease in cardiac output is associated with an increase in CAVI values at different degrees of HUT. This association provides further insight into the postural link between cardiac output and arterial compliance.展开更多
Objective To study thechanges of baroreflex sensitivity (BRS) during head - up tilt test (HUT) in patients with vasovagal syncope (VS), and to examine the relationship between baroreflex sensitivity and neurohormonal ...Objective To study thechanges of baroreflex sensitivity (BRS) during head - up tilt test (HUT) in patients with vasovagal syncope (VS), and to examine the relationship between baroreflex sensitivity and neurohormonal factors. Furthermore, to investigate the effects of the changes of BRS on VS. Methods Forty - two patients with unexplained syncope (Among the 42 patients, there were 22 patients with positive HUT and 20 patients with negative HUT respectively) and 20 healthy volunteers (with negative HUT) underwent passive head - up tilt testing, Ante-cubital vein blood samples were taken before and after HUT, or at syncope. The fasting plasma endothelin , serum nitric oxide (NO), serum NE were measured, the BRS was assessed on the basis of the linear regression slope the RR interval versus systolic arterial blood pressure during the increment in blood pressure after intravenous administration of phenylephrine. Results (1) During the syncope, the BRS significantly reduced in HUT(+) group than baseline. At the end of tilt, the level of plasma ET, serum NO in patients with positive HUT significantly increased compared with baseline or normal controls, and the plasma concentration of NE also had the trend of increase. (2) By multiple regression analysis, a significant negative correlation was found between baroreceptor sensitivity and the plasma ET, NO at the end of HUT in patients with positive HUT, but there was no relationship between BRS and NE. Conclusions During the syncope occure, the BRS in patients with VS decreased significantly compared with normal controls. The abnormal plasma ET, NO concen-tration might contribute to the mechanism of VS.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
To investigate age and sex distribution of vasovagal syncope （VVS） patients undergoing head-up tilt table test （HUTT） at a tertiary hospital. The details of syncope patients who underwent HUTT at our department of...To investigate age and sex distribution of vasovagal syncope （VVS） patients undergoing head-up tilt table test （HUTT） at a tertiary hospital. The details of syncope patients who underwent HUTT at our department of cardiac function from January 2004 to December 2010 were reviewed. Of the 1 799 patients who underwent the HUTT, 854 tested positive, of which 558 （65.3%） were women, which were more than the women in the negative group （450, 47.6%） （p〈0.05）. VVS patients showed a bimodal age distribution between 11 and 20 years of age and in the fourth decade. In almost all age groups, mixed response was the highest compared with vasodepressor and cardioinhibitory. VVS patients who underwent HUTT indicate bimodal distribution peaking before the second decade and the fourth decade. The incidence of females was twice that of males before the sixth decade, and old age occupies a small percentage of VVS with no other comorbidities.展开更多
文摘Background: Syncope is a relevant health problem in military environments. Reliable diagnosis is challenging. Tilt table testing is an important tool for syncope diagnosis. The aim of this study was to determine whether signs such as prodromal symptoms, co-morbidity, frequency of syncopal events, body length, body mass index, and electrocardiography(ECG) abnormalities can be used to predict the success of tilt table testing at diagnosing syncope.Methods: Data from 100 patients with histories of syncope or pre-syncope, who were diagnosed using head-up tilt table testing, were retrospectively analyzed in a cross-sectional analysis. The diagnostic procedure was based upon a modified version of the Westminster protocol without any pharmacological provocation. Results: Patients showing pathological reaction patterns during tilt table testing suffered from prodromal symptoms, such as dizziness and sweating, significantly more often. The patients reported more injuries resulting from syncopal events and more previous syncopal events, and the prevalence of co-morbidity was greater among patients presenting negative findings during tilt testing. An asthenic-leptosomal physique was not confirmed as a risk factor for syncopal events as is the case for idiopathic arterial hypotension. However, patients with pathological reaction patterns during tilt table testing were significantly taller. This finding was detected for both females and males. No significant predictors were found in the ECG patterns of patients showing syncope during tilt table testing.Conclusions: Frequency of prior syncope and prodromal symptoms, and increased body length with an otherwise good state of health influence the predictive value of tilt table testing for syncope diagnosis. In particular, if these factors are present, tilt table testing should be considered part of the diagnostic algorithm for soldiers with recurrent syncope.
文摘Background:Syncope is a relevant health problem in military environments.Reliable diagnosis is challenging.Tilt table testing is an important tool for syncope diagnosis.The aim of this study was to determine whether signs such as prodromal symptoms,co-morbidity,frequency of syncopal events,body length,body mass index,and electrocardiography abnormalities can be used to predict the success of tilt table testing at diagnosing syncope.Methods:Data from 100 patients with histories of syncope or pre-syncope,who were diagnosed using head-up tilt table testing,were retrospectively analyzed in a cross-sectional analysis.The diagnostic procedure was based upon a modified version of the Westminster protocol without any pharmacological provocation.Results:Patients showing pathological reaction patterns during tilt table testing suffered from prodromal symptoms,such as dizziness and sweating,significantly more often.The patients reported more injuries resulting from syncopal events and more previous syncopal events,and the prevalence of co-morbidity was greater among patients presenting negative findings during tilt testing.An asthenic-leptosomal physique was not confirmed as a risk factor for syncopal events as is the case for idiopathic arterial hypotension.However,patients with pathological reaction patterns during tilt table testing were significantly taller.This finding was detected for both females and males.No significant predictors were found in the electrocardiogram patterns of patients showing syncope during tilt table testing.Conclusions:Frequency of prior syncope and prodromal symptoms,and increased body length with an otherwise good state of health influence the predictive value of tilt table testing for syncope diagnosis.In particular,if these factors are present,tilt table testing should be considered part of the diagnostic algorithm for soldiers with recurrent syncope.
文摘To study the role of autonomic nervous system in the period of developing syncope induced by head-up tilt test(HUT), we analysed the changes of heart rate power spectral density(HRPSD) in 50 patients with unexplained syncope, including 15 positive patients (Group 1) and 35 negative patients(Group 2), and 15 negative healthy persons(Group 3) in 5 minute periods before and after tilting and 5 minutes before the end of test. HRPSD and their changes in total(T), very low-frequence(VLF), low-frequence(LF), high-frequence(HF) and the ratio of low/high frequence(LF/HF) were similar (P>0.05) 5 minutes before and after tilting among three groups. Five minutes before the end of test, Group 1 had obvious increase of T, VLF, LF and LF/HF while Group 2 and 3 had not such significant changes. There was significant difference(P<0.01) compared Group 1 with Group 2, 3. The results showed that the abnormal regulatory function of autonomic nervous system played an important role in the mechanism of symcope induced by HUT, the positive group had abnormal increase of sympathetic tone and imbalance of sympathetic/parasympathetic neural tone before syncope appeared.
文摘The cardio-ankle vascular index (CAVI) is a new index of arterial stiffness that can be measured with a VaSera VS-1000 device. An association between certain arterial stiffness indices and cardiac function has been found but has not yet been validated. The aim of this study was to establish whether any significant relationship exists between cardiac index (CI) and CAVI. Twenty healthy male volunteers with a mean age of 30 ± 5 years and a mean BMI of 23.1 ± 1.1 kg/m2 participated in the study. CO was estimated using a Doppler technique, and CAVI was measured with a VaSeraVS-1000 device. A motorised tilting table was used to achieve head-up tilt (HUT) angles of 0°, 30°and 60°, to modify the peripheral sympathetic outflow. We found that there was a significant inverse correlation between CI and the degree of head-up tilt, ( for 0°and 30°;for 0° and 60°, p for both;for 30° and 60°, ). CAVI showed a significant positive correlation relative with the degree of HUT, ( for 0° and 30°;for 0° and 60°;for 30° and 60°, for all). A significant negative correlation was found between CI and CAVI r = - 0.47, p Additionally, a significant p increase in PVR values was observed for increasing HUT values. In conclusion: An inverse relationship between CI and CAVI was shown;a decrease in cardiac output is associated with an increase in CAVI values at different degrees of HUT. This association provides further insight into the postural link between cardiac output and arterial compliance.
文摘Objective To study thechanges of baroreflex sensitivity (BRS) during head - up tilt test (HUT) in patients with vasovagal syncope (VS), and to examine the relationship between baroreflex sensitivity and neurohormonal factors. Furthermore, to investigate the effects of the changes of BRS on VS. Methods Forty - two patients with unexplained syncope (Among the 42 patients, there were 22 patients with positive HUT and 20 patients with negative HUT respectively) and 20 healthy volunteers (with negative HUT) underwent passive head - up tilt testing, Ante-cubital vein blood samples were taken before and after HUT, or at syncope. The fasting plasma endothelin , serum nitric oxide (NO), serum NE were measured, the BRS was assessed on the basis of the linear regression slope the RR interval versus systolic arterial blood pressure during the increment in blood pressure after intravenous administration of phenylephrine. Results (1) During the syncope, the BRS significantly reduced in HUT(+) group than baseline. At the end of tilt, the level of plasma ET, serum NO in patients with positive HUT significantly increased compared with baseline or normal controls, and the plasma concentration of NE also had the trend of increase. (2) By multiple regression analysis, a significant negative correlation was found between baroreceptor sensitivity and the plasma ET, NO at the end of HUT in patients with positive HUT, but there was no relationship between BRS and NE. Conclusions During the syncope occure, the BRS in patients with VS decreased significantly compared with normal controls. The abnormal plasma ET, NO concen-tration might contribute to the mechanism of VS.
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.
基金Supported by the National Natural Science Foundation of China (30972954)
文摘To investigate age and sex distribution of vasovagal syncope （VVS） patients undergoing head-up tilt table test （HUTT） at a tertiary hospital. The details of syncope patients who underwent HUTT at our department of cardiac function from January 2004 to December 2010 were reviewed. Of the 1 799 patients who underwent the HUTT, 854 tested positive, of which 558 （65.3%） were women, which were more than the women in the negative group （450, 47.6%） （p〈0.05）. VVS patients showed a bimodal age distribution between 11 and 20 years of age and in the fourth decade. In almost all age groups, mixed response was the highest compared with vasodepressor and cardioinhibitory. VVS patients who underwent HUTT indicate bimodal distribution peaking before the second decade and the fourth decade. The incidence of females was twice that of males before the sixth decade, and old age occupies a small percentage of VVS with no other comorbidities.
文摘目的：探讨年龄和性别对疑似血管迷走性晕厥（VVS）患者进行直立倾斜试验（HUTT）诊断结果的影响。方法：收集2008-08至2012-12在阜外心血管病医院进行HUTT检查的患者共1 223例,其中男性549例。患者年龄7-79岁,按年龄依次分为≤20岁组、21-40岁组、41-60岁组和〉60岁组。HUTT包括30 min的基础试验阶段和（或）20 min的药物（硝酸甘油）试验阶段。根据阳性患者血压和心电学的变化,VVS分为血管抑制型、心脏抑制型和混合型。结果：HUTT阳性率为51%（624/1 223例）,女性阳性率高于男性（60.1%vs 39.9%,P=0.001）。四组阳性率依次为68.3%、49.1%、48.6%和47.9%。阳性患者中混合型占51.4%（321例）,血管抑制型占28.7%（179例）,心脏抑制型占19.9%（124例）。HUTT阳性类型的分布受年龄因素的影响（男性：χ2=15.65,P=0.016;女性：χ2=18.84,P=0.004）,性别间差异无统计学意义（P〉0.05）。基础试验阶段74.8%的阳性反应出现在试验开始后22.5（17.5-27.5）min,但无年龄性别差异（P〉0.05）;药物试验阶段81.9%的阳性反应出现在试验开始后7.5（5-10）min,女性发生阳性反应的时间比男性提前（7.5 min vs 10 min,P=0.004）,无年龄差异。结论：HUTT诊断VVS的阳性率、阳性分型和发生阳性反应的时间存在年龄和性别差异。
