Runmei Zou

The circadian rhythm of syncopal episodes in patients with neurally mediated syncope

OBJECTIVE To explore the circadian rhythm of neurally mediated syncope (NMS). METHODS 411 patients with NMS (165 males and 246 females aged from 3 to 68years) were included in the study. All subjects underwent head-up tilt test (HUTT) and were carefully asked about the number of syncopal attacks and the periods (morning 06:00am-12:00am, afternoon 12:00am-18:00pm, evening 18:00pm-24:00pm, night 00:00am-06:00am) in which episodes occurred in. RESULTS (1) Syncopal attacks of all patients tended to occur in the morning (P=0.010); there was a statistical difference in the frequency of episodes in four periods through the day in HUTT positive patients (P=0.001), but there was no significant change of episodes within a day in HUTT negative group; and there was no statistical difference in circadian syncope distribution between HUTT negative and HUTT positive group or among patients with different HUTT responses (the orthostatic hypotension (OH) and orthostatic hypertension (OHT) patients were excluded). (2) The syncopal attacks of morning hours occurred more in males than females, but the episodes in the evening occurred more in females than males (P=0.034). (3) The younger the patients were, the chance of syncopal attacks in the morning increased; the older the patients were, they may have more episodes at night (P<0.001). CONCLUSIONS A distinct circadian variation in the frequency of syncopal episodes exists, with a peak in the morning, and there were statistical differences in circadian rhythm of syncopal episodes regarding gender and age.

The changes of electrolytes in serum and urine in children with neurally mediated syncope cured by oral rehydration salts

OBJECTIVE To detect the changes of electrolytes in serum and urine in children with nerve mediated syncope (NMS) cured by oral rehydration salts (ORS). METHOD From May 2014 to April 2015, 135 patients with symptoms like unexplained syncope and presyncope were administrated in our hospital, including 60 boys and 75 girls, aged between 4 and 16 (10.2±2.7) years. After head-up tilt test (HUTT), their electrolytes in serum and urine were examined. Those who were positive to the HUTT received ORS and health education, while others were only treated by health education. With the period of subsequent visit arranging 21-154 (42.6±27.7) days, the improvement of their clinical manifestation were inquired and electrolytes in serum and urine were re-tested. RESULT (1) The total effective percentage of ORS treatment was 63.0%, and the negative conversion rate of HUTT was 48.2%. (2) In the first time of visit to hospital, there was no statistical significance between the HUTT-positive and the HUTT- negative in serum electrolytes, 24-h urine electrolytes and 24-h urine volume (P>0.05). (3) In the return visit to hospital, the serum calcium and serum phosphorus in the HUTT-positive were higher than those in the HUTT-negative (P<0.05). (4) With the intake of ORS, 24-h urine sodium, 24-h urine chlorine and 24-h urine volume were improved than pre-treatment (P<0.05 or 0.01). CONCLUSION ORS was an effective treatment to the NMS children, with 24-h urine volume and urine chloride increasing.

Assessment of Efficacy of Oral Rehydration Salts in Children With Neurally Mediated Syncope of Different Hemodynamic Patterns

Objective: To assess the efficacy of oral rehydration salts in children with neurally mediated syncope of different hemodynamic types. Methods: Children with unexplained syncope or pre-syncope who visited or were hospitalized between March 2012 and February 2015 were enrolled in the study. Checked by the head-up tilt test, 105 children (aged 4-18 years, with a mean age of 11.96 ± 2.86 years) were diagnosed with neurally mediated syncope. Of them, 73 had vasovagal syncope (vasodepressor type in 46, mixed/cardioinhibitory types in 27), and 32 had postural orthostatic tachycardia syndrome. They were randomized into the oral rehydration salts plus health education group (n = 55) and the health education alone group (n = 50). All treated children were followed up. The follow-up time ranged from 6 to 25 (14.82 ± 6.13) months. Short-term effects were assessed according to the recurrence of clinical symptoms and reviews of head-up tilt test results 6 months after drug withdrawal. Long-term effects were compared between both groups of children with neurally mediated syncope. Results: Short-term effect: No significant differences were found in subjective response rate and head-up tilt test negative results rate among different hemodynamic types (P > .05). Long-term effect: Compared with the health education alone group, the cumulative response rate increased after treatment with oral rehydration salts (P < .05). Among oral rehydration salts–treated children, the cumulative response rate was higher in those with vasodepressor vasovagal syncope than with mixed/cardioinhibitory vasovagal syncope (P < .05). Conclusion: Compared with children with mixed/cardioinhibitory vasovagal syncope, oral rehydration salt is more suitable for those with vasodepressor vasovagal syncope.

[Differences of age and gender in orthostatic hypertension-a single-center study].

OBJECTIVE To explore the differences of Chinese peoples age and gender in orthostatic hypertension (OHT) by a single-center experience study.
 METHODS A total of 2 994 patients with unexplained syncope and dizziness, who were outpatients or had been hospitalized in Second Xiangya Hospital, Central South University from January 2000 to August 2012, were chosen and subjected to the head-up tilt table test (HUTT). Their ages ranged from 2.00 to 78.00 years old, with an average at 19.07±14.78 years old. There were 1 406 and 1 588 cases for male and female, respectively. A total of 745 patients were OHT, who were divided into a adult group (≥18 years old, 247/904 cases) and a children group (<18 years old, 498/2 090 cases). The difference of the occurrence rate, classification, and 3 min quantity of blood pressure were analyzed.
 RESULTS 1) The incidence of OHT in HUTT was 24.88% (745/2 994 cases). There was no statistical difference between the males and the females(25.75% vs 24.12%, χ2=1.058, P>0.05), but it was higher in the adult group compared with that in the children group (27.05% vs 23.83%, χ2=4.125, P=0.042). There were 52 cases (6.98%) of high systolic and high diastolic blood pressure (sOHT merge dOHT), 16 cases (2.15%) of simple high systolic blood pressure OHT (sOHT), and 677 cases (90.87%) of simple high diastolic blood pressure OHT (dOHT) in the 745 patients with OHT. The incidence of dOHT and sOHT merge sOHT in the adults group were significantly higher than those in the children group (1.11% vs 0.29%, χ2=7.965, P<0.01; 2.88% vs 1.24%, χ2=9.849, P<0.01, respectively); there was no statistical difference in simple dOHT between males and females (23.56% vs 22.20%, χ2=0.668, P>0.05); there was also no statistical difference in sOHT plus dOHT and dOHT between males and females (sOHT merge dOHT: 1.71% vs 1.76%, χ2=0.014, P>0.05; dOHT: 23.68% vs 21.66%, χ2=1.742, P>0.05; 1.71% vs 1.76%, χ2=0.014, P>0.05, respectively); but the dOHT was significantly higher in the males than that in the females in the children group (24.53% vs 19.74%, χ2=6.933, P>0.05). 2) There was no difference in the increment of systolic blood pressure in sOHT plus dOHT [(25.62±4.96) mmHg vs (23.54±5.83) mmHg, t=1.385, P>0.05] and the increment of diastolic blood pressure in dOHT [(13.46±3.49) mmHg vs (13.23±3.22) mmHg, t=0.840, P>0.05] between the adults group and the children group. There was no difference in the increment of systolic blood pressure in sOHT [(25.44±4.96) mmHg vs (23.68±5.35) mmHg, t=1.411, P>0.05] and the increment of diastolic blood pressure in dOHT [(14.09±4.28) mmHg vs (13.05±3.82) mmHg, t=1.887, P>0.05] between the adults group and the children group.
 CONCLUSION The incidence of OHT is higher in the adults group than that in the children group. There is no difference in systolic and diastolic blood pressure increment within 3 minutes during HUTT between the adults and children.

[Changes in P-wave, T-wave, and ST segment amplitude in 12 lead electrocardiogram in children with breath holding spell].

OBJECTIVE To explore the change of the amplitude of P wave, T wave and ST segment of 12 lead electrocardiogram (ECG) in children with breath holding spell.
 METHODS A total of 29 children (24 males and 5 females) with breath holding spell in Second Xiangya Hospital, Central South University were enrolled for this study from October, 2009 to September, 2015. Their ages ranged from 3 months to 6 years, with an average of 1.82±1.27 years old. The control group consisted of 30 age-matched and gender-matched healthy children. All subjects were underwent electrocardiography by the SR-1000A comprehensive automatic electrocardiograph analyzer, and the changes of the ECG parameters were compared between the two groups.
 RESULTS Compared with the control group, the amplitude of P-wave of V5 lead was decreased [(44.10±23.98) vs (58.30±21.19) μV, P<0.05], the amplitude of T-wave of V6 lead was increased [(423.80±122.6) vs (350.00±105.73) μV, P<0.05], the amplitude of ST segment of II lead was increased [(84.80±39.97) vs (57.30±38.77) μV, P<0.05], the amplitude of ST segment of aVR lead was increased [(-77.60±37.41) vs (-51.00±33.46) μV, P<0.05], the amplitude of ST segment of aVL lead was increased [(35.20±28.24) vs (17.70±33.90) μV, P<0.05], the amplitude of ST segment of V5 lead was increased [(111.00±59.36) vs (69.00±36.33) μV, P<0.05], the amplitude of ST segment of V6 lead was increased [(79.30±45.51) vs (51.30±33.19) μV, P<0.05]. 
 CONCLUSION The children with breath holding spell have autonomic nerve dysfunction. The amplitude of ST segment changes is sensitive.

Incidence of long (short) PR interval in electrocardiogram among healthy people in Changsha and its clinical significance

OBJECTIVE To analyze the incidence of long (short) PR interval in electrocardiogram among healthy people in Changsha and the clinical significance.
 METHODS Twelve-lead body surface electrocardiogram was taken to measure the heart rates and PR intervals from 4 025 healthy individuals (age range from 6 min after birth to 83 years old) who performed physical examination from Jan, 1993 to Dec, 2012 in the Second Xiangya Hospital, Central South University. Statistics were analyzed by SPSS 16.0.
 RESULTS The total incidence of short PR interval was 19.65% (791/4 025). The age group from birth to 13 years old had a higher incidence than the other age groups (χ2=432, P<0.01). The age groups from 1 month after birth and from 1 month to younger than 1 year-old displayed the highest incidences (43.29% and 44.34%, respectively). The lowest incidences were obtained from the 14-17 year-old, 40-49 year-old and 50-59 year-old groups (0.20%, 0.41%, and 0.33%, respectively). The total incidence of long PR intervals was 3.58% (144/4 025). The 1 year-old group had the highest incidence (6.74%), which decreased with the increase of age. The lowest incidence of long PR intervals occurred in the age group from 14-17 years old, which gradually increased after 50 years old. There were no significant differences in long (short) PR intervals between the gender (P>0.05).
 CONCLUSION The incidence of long (short) PR intervals varies in different age groups of healthy people. The incidences of long (short) PR intervals in children before 10 years old are higher than those in adults, especially the short PR intervals, as a result of the heart rate affected by childhood autonomic nervous function and the change in atrial volume with age. Adults have long (short) PR interval should be regularly followed-up to prevent cardiovascular events.

The ventricular late potentials in children with vasodepressor response of vasovagal syncope

OBJECTIVES To discuss ventricular late potentials (VLPs) in children with vasodepressor response of vasovagal syncope (VVS-V). METHODS 184 children diagnosed as VVS-V by head-up tilt test (HUTT) were enrolled as VVS-V group, 105 age and gender matched healthy individuals without syncope were used as control group, then signal-averaged electrocardiogram was measured. RESULTS HR was decreased [(83.98±12.27) vs (87.28±13.75)bpm, P<0.05] in VVS-V group compared with control group. The prevalence of positive VLPs was not significantly different between the two groups. However the absolute values of TQRS [(84.89±12.05) vs (81.21±8.23)ms, P<0.01], RMS40 [(28.73±7.23) vs (26.89±7.36)μV, P<0.05] and LAS40 [(62.43±19.17) vs (56.79±1.83)ms, P<0.05] were significantly prolonged in VVS-V group compared with control group, and more patients in VVS-V group had abnormal prolonged LAS40 (94.57% vs 83.80%, P<0.01). CONCLUSIONS The prevalence of positive VLPs was not significantly different, TQRS, RMS40, LAS40 were longer in children with VVS-V in comparison with healthy individuals, and the abnormal LAS40 occurred in a higher proportion of VVS-V group.

Head-up tilt test results in child twins with nervous mediated syncope

OBJECTIVE To investigate the familial genetic characteristics of syncope in children. METHODS A detailed medical history was taken from four twin pairs of children complaining of dizziness, headache, chest tightness, chest pain, prodromal symptoms of syncope or syncope, meanwhile, these patients were given routine physical examination, 12-lead ECG, echocardiography, Holter ECG, EEG, MRI of the head and other tests to exclude cardio-cerebrovascular and pulmonary diseases, with those with unknown origin for syncope undergoing head-up tilt test (HUTT) and inquiry of detailed family history. RESULTS The four pairs of twins with syncope beginning at 7-12years and induced mostly by standing position (4/5), and positive family history was noted in two pairs. Vasovagal syncope (VVS)-vasoinhibitory response pattern was predominant in HUTT (4/5). The results and the response pattern in HUTT might diversify between two members within same twin pair: one appeared as vasoinhibitory response pattern and one postural orthostatic tachycardia syndrome (POTS) pattern in the first pair, one vasoinhibitory response pattern and one negative response pattern in the second pair, vasoinhibitory response pattern in the third pair and negative response pattern in the fourth pair. CONCLUSIONS The hereditary factors may play a more important role in younger children with syncope. Environment and psychological factors may induced syncope attack. The results and the response pattern in HUTT are diversified and which might different between two members within twin pair.