直立倾斜试验阳性反应特点及临床特征

目的探讨儿童直立倾斜试验(HUT)阳性反应特点及临床特征。方法以49例不明原因晕厥及只有晕厥先兆症状患儿为研究对象,直立倾斜试验(HUT)(倾斜角度60度,试验持续时间45min)过程中动态观察血压、心率、心电图变化,分析其阳性反应血流动力学改变及其临床特征。结果HUT阳性反应时常见晕厥先兆症状为头痛、头晕、胸闷、气短、面色苍白、出汗、乏力、站立不稳、视物模糊、听觉下降及消化道症状。28例阳性反应中,血管抑制型反应7例(25%).表现为血压下降,心率加快;心脏抑制型反应3例(11%),表现为心率减慢,血压无变化;混合型反应4例(14%),表现为心率、血压均明显下降。体位性心动过速综合征(POTS)10例(36%),表现为HUT10min内心率增快30次以上或心率达120次/min以上。直立性低血压4例(14%).表现为HUT3min内血压明显下降。结论HVT阳性反应症状可作为儿童不明原因晕厥鉴别诊断的主要依据。

Characteristics and Clinical Features of Positive Response for Head-Up Tilt Test in Children

Objective To study the characteristics and clinical features of positive response during head - up tilt test (HUT) in children. Methods Forty- nine cases of syncope and aura of syncope were included in the study. All of them underwent HUT (tilt angle 60 degree,lasting 45 minutes). During the test,children' blood pressure,heart rate.electrocardiography and clinical symptoms and signs were dynamically observed. Results The common syncope aura symptoms were headache, dizziness, chest distress, difficulties in breathing, pale, perspiration, blurred vision, auditus depression and symptoms related to digestive symptoms. Among the 28 positive cases, 7 cases were of vaso - inhibitory pattern (25%), with a decrease in blood pressure and an increase in heart rate, 3 cases inhibitory pattern (11%), with a decrease in heart rate but withoilt'blood pressure changes, 4 cases mixed pattern (14 %), with decreases in heart rate and blood pressure obviously, 10 eases POTS (36%), with an increase in heart rate by 30 bpm or up to 120 bpm within 10 minutes while testing, and 4 cases orthostatic hypotension (14%), with a decrease in blood pressure within 3 minutes. Conclusion HUT can be regarded as the main tool in differential diagnosis of unexplained syncope in children.