儿童青少年体位性心动过速综合征卧位与立位心电图T波及ST段振幅变化

The changes of amplitude of T wave and ST segment between the supine and orthostatic electrocardiogram in children and adolescents with postural tachycardia syndrome

目的探讨儿童青少年体位性心动过速综合征（POTS）卧位与立位心电图T波及ST段振幅变化。方法选取2013年8月至2016年1月因不明原因头晕、头痛、晕厥等症状在本院儿童晕厥专科门诊就诊、通过直立倾斜试验（HuTT）诊断为POTS的儿童青少年74例（POTS组）；按年龄和性别匹配同期在我院儿童保健门诊健康检查的儿童青少年64例为对照（对照组）。描记卧位与立位12导联体表心电图，程序自动分析结合人工干预测量卧位与立位心电图的心率及12导联心电图T波和ST段振幅。结果（1）立位与卧位比较：POTS组心率增加[（105．2±16．3）次／min比（83．8±18.0）次／min，t=-7．598，P〈0．01）]，Ⅰ[（0．28±0．14）mV比（0．33±0．11）mV，t=2．598，P〈0．05）]、Ⅱ[（0．28±0．12）mV比（0．39±0．13）mV，t=5．340，P〈0．01）]、Ⅲ[（0．00±0．19）mV比（0．07±0．11）mV，t=3．041，P〈0．01）]、aVF[（0．14±0．13）mV比（0．23±0．11）mV，t=4．505，P〈0．01）]、V4[（0．33±0．21）mV比（0．51±0．23）mV，t=4．938，P〈0．01）]、V5[（0．37±0．10）mV比（0．50±0．15）mV，t=7．764，P〈0．01）]、V6[（0．254-0．10）mV比（0．37±0．10）mV，t=7．538，P〈0．01）]导联T波振幅降低，aVR导联T波振幅增高[（-0．27±0．11）mV比（-0．36±0．10）mV，t=-5．023，P〈0．01）]，V5导联ST段振幅增高[（0．07±0．04）mV比（0．06±0．04）mV，t=-2．309，P〈0．05）]。（2）与对照组比较：POTS组心率差增加[（-21．4±14．0）次／min比（-10．7±11．4）次／min，t=4．875，P〈0．01）]，Ⅰ[（0．05±0．10）mV比（-0．01±0．15）mV，t=～3．161，P〈0．01）]、Ⅱ[（0．11±0．12）mV比（0．07±0．12）mV，t=一2．243，P〈0．05）]、V4l（0．18±0．18）mV比（0．07±0．20）mV，t=-3．282，P〈0．01）]、V5[（0．18±0．11）mV比（0．14±0．13）mV，t=-2．013，P〈0．05）]、V6[（0．13±0．08）mV比（0．08±0．10）mV，t=-3．364，P〈0．01）]导联T波振幅差增大，aVR导联T波振幅差负值增大[（-0．09±0．08）mV比（-0．03±0．08）mV，t=4．109，P〈0．01）]。（3）Logistic回归分析：心电图卧位、立位心率差及V5、V6导联T波振幅差对POTS诊断有统计学意义（P〈0．05）。（4）诊断性试验评价：当同时出现心电图卧位、立位心率差≥15次／min，T波振幅差在V5导联及V6导联分别≥0．10mV时，诊断POTS的敏感度37．8％，特异度为81．3％。（5）POTS儿童青少年随访：无论H【rI]r反应类型保持不变或转为阴性，较最初诊断时立位与卧位心电图T波及sT段振幅差均未见明显改变（P〉0．05）。结论卧位与立位心电图心率差及V5、V6导联T波振幅差对儿童青少年POTS具有诊断价值。

Objective To investigate the changes of amplitude of T wave and ST segment between the supine and orthostatic electrocardiogram in children and adolescents with postural tachycardia syndrome （POTS）. Methods A total of 74 children and adolescents diagnosed as POTS by head-up tilt test （HUTI＇）, who complained of unexplained dizziness, headache, syncope or other symptoms, were chosen as POTS group. A total of 64 children and adolescents who did the health check in our child health clinic were selected as control group by age and sex in the same period. All the cases in this study came from the syncope specialized clinic or inpatient department of the Second Xiangya Hospital, Central South University, from August 2013 to January 2016. The heart rate and the 12-lead T-wave and ST-segment amplitude of the supine and orthostatic electrocardiogram were measured by software and manual intervention. Results （ 1 ） Compared with supine electrocardiogram, the heart rate of orthostatic eleetrecardiogram of POTS group increased （ 105.2 ± 16.3 ） times/min vs. （ 83.8 ± 18.0 ） times/min, t = - 7. 598, P 〈 0. 01 ], the T-wave amplitude decreased in lead Ⅰ [ （0. 28 ±0.14） mVvs. （0.33±0.11） mV,t=2.598,P〈0.05], Ⅱ[（0.28 ±0.12） mV vs. （0.39 ±0. 13） mV,t =5. 340,P 〈0. 01], Ⅲ[ （0. 00 ±0. 19） mV vs. （0. 07 ±0. 11） mV,t =3.041, P 〈0.01 ] ,aVF [（0. 14 ±0. 13） mV vs. （0. 23 ±0. 11） mV,t =4. 505,P 〈0. 01 ] ,V4 [ （0. 33 ±0. 21 ） mV vs. （0.51 ±0. 233 mV,t =4. 938,P 〈0.01 ] ,V5[ （0. 37 ±0. 10） mV vs. （0. 50 ±0. 15） mV,t =7. 764,P 〈 0.01] and V6[ （0. 25 ±0. 10） mV vs. （0.37 ±0. 10） mV,t =7.538,P 〈0. 01 ] ,the T-wave amplitude increased in lead aVR[ （ -0. 27 ±0.11） mVvs. （-0.36±0.10） mV,t= -5.023,P〈0.01],and the ST- segment amplitude increased in lead V5 [ （0.07 ±0.04） mV vs. （0.06 ±0.04） mV ,t = -2. 309 ,P 〈0.05]. （2） Compared with control group, the difference of heart rate of POTS group increased [ （ -21.4 ± 14. 0） times/min vs. （ - 10. 7 ± 11.4）times/min,t =4. 875,P 〈0. 01] .and the difference of T-wave amplitude increased in lead I [ （0.05 ±0.10） mV vs.（-0.01 ±0.15） mV,t= -3. 161,P〈0.01],Ⅱ（0.11±0.12） mV vs. （0.07 ±0.12） mV,t= -2.243,P〈0.05],V4[（0.18 ±0.18） mV vs. （0.07 ±0.20） mV,t= -3.282.P〈0.01],V5[（0.18±0.11） mV vs. （0.14 ±0.13） mV,t= -2.013,P〈0.05] andV6[（0.13 ±0. 08） mV vs. （0. 08 ± 0. 10） mV, t = - 3.364, P 〈 0. 01 ], and the difference of T-wave amplitude in- creased significant in lead aVR[ （ -0. 09 ±0. 08） mV vs. （ -0. 03 ±0. 08） mV,t =4. 109,P 〈0. 01 ]. （3） Logistic regression analysis ：the difference of heart rate and T-wave amplitude in lead V5 and V6 on supine and orthostatic electrocardiogram was statistically valuable for the diagnosis of POTS （P 〈 0. 05）. （4） Diagnostic test evaluation：when the difference of heart rate ≥ 15 times/min,of T-wave amplitude in lead V5 and lead V6 ≥ 0. 10 mV separately, on supine and orthostatic electrocardiogram at the same time, the sensitivity of the diagnosis of POTS was 37.8% and the specificity was 81.3%. （5）The follow-up of children and adoles- cenls with POTS showed no significant difference of T-wave amplitude and ST-segment amplitude on orthostotic and supine ECG comparing to the initial diagnosis ,regardless of the type of HUIT reaction remained or turned negative （ P 〉 0. 05）. Conclusion The difference of heart rate and of T-wave amplitude in lead V5 and V6 are valuable for the diagnosis of POTS in children and adolescents.