Analysis of the results of head-up tilt test in syncope children

Objective To explore the familial genetic characteristics of twins syncope in children. Methods Four pairs of twins with unexplained dizziness, headache, chest tightness, chest pain, pre-syncope and syncope were received head-up tilt test (HUTT) and family history of syncope were inquired.The age, gender, clinical manifestations were analyzed and the HUTT hemodynamic response were performed, and interviewed via telephone. Results The onset age of 4 pairs of twins ranged from 7 to 12 years old, less than 15 years, the median age of the first syncope episodes.Cause of syncope was primarily standing(4/5 cases), 2 pairs had syncope positive family history.HUTT hemodynamic response type was mainly vasodepressor syncope(4/5 cases). HUTT result and hemodynamic response type were not completely consistent in the same twins.One case of the first twins was vasodepressor syncope and postural orthostatic tachycardia syndrome.One case of the second twins was vasodepressor syncope, while the other was negative.The third twins were vasodepressor syncope.The fourth twins were negative.HUTT results of the 4 twins were diverse, indicating that environment, psychological factors may get involved in syncope episodes. Conclusions The familial genetic factors of the children with syncope may play an important role in the young age group.Environment and psychological factors may be induce syncope attack.HUTT results of twins are diverse.HUTT result and hemodynamic response type can be inconsistent in the same twin. Key words: Twin; Syncope; Family; Head-up tilt test