先天性心脏病术后患儿6分钟步行试验前后心电参数对照研究

目的 研究先天性心脏病（CHD）患儿术后中远期随访6 min步行试验（6MWT）前后心电参数的变化.方法 选取复旦大学附属儿科医院心血管中心经心脏外科手术纠治的年龄≥3岁且随访时间≥6个月的CHD患儿为CHD组;选取健康儿童作为对照组.将CHD组和对照组同时分为3～5岁、～8岁、～12岁和～15岁亚组.CHD组根据CHD类型分为复杂CHD亚组和简单CHD亚组.比较各组6MWT前后P波离散度（Pwd）、QRS时限和QT离散度（QTd）变化.结果 CHD组89例,男51例,女38例,行外科手术时的平均年龄为（3.0±2.3）岁（36 d至11.0岁）,术后平均随访时间为（3.6±3.2）（0.5～14.2）年.3～5岁、～8岁、～12岁和～15岁亚组分别为39、27、11和12例.复杂和简单CHD亚组分别为29和60例.对照组133名（男75名,女58名）,3～5岁、～8岁、～12岁和～15岁亚组分别为26、39、39和29名.①CHD组和对照组各年龄亚组6MWT后Pwd、QRS时限和QTd均较6MWT前减小,但差异无统计学意义（均P〉0.05）.②CHD组3～5岁和～12岁亚组6MWT前QTd均较对照组显著增大,3～5岁亚组：（0.025±0.018） vs （0.012±0.011） s,P＝0.004;～12岁亚组：（0.029±0.014） vs （0.019±0.012） s,P＝0.019.CHD组各年龄亚组6MWT后QTd与对照组比较差异无统计学意义（均P〉0.05）.③CHD组～8岁和～15岁亚组6MWT前后QRS时限均较对照组显著延长（P分别为0.000和0.007）;各年龄亚组6MWT后差异均有统计学意义.④复杂CHD亚组6MWT前后QRS时限均较简单CHD亚组延长,6MWT前：（0.102± 0.025） vs （0.080 ± 0.021） s,P=0.000;6MWT后：（0.103 ± 0.026） vs （0.080 ± 0.021） s,P=0.000,两亚组6MWT前后Pwd和QTd差异均无统计学意义.结论 CHD术后中远期随访患儿心脏电活动仍不稳定,但其6MWT前后心电参数Pwd、QRS时限及QTd的变化趋势与健康儿童相一致,提示亚极量运动有助于增强心脏电活动的稳定性.

The study of ECG-parameter change in postoperative congenital heart disease children pre- and post-six-minute walking test

Objective To study ECG-parameters pre- and post-six-minute walking test （6MWT）among children after congenital heart disease （CHD） surgery. Methods Children after CHD surgery （complicated or simple CHD） and followed up over 6 months from Children＇s Hospital of Fudan University were enrolled in CHD group, and healthy children were enrolled in control group, both groups were categorized into 4 subgroups by age at testing： 3 -5, -8, - 12 and - 15 years age-subgroups. ECG-parameters including P wave dispersion （Pwd）, QRS duration and QT dispersion （QTd） were studied before and after 6MWT between the two groups. Results Eighty-nine children with CHD including 29 complicated CHD and 60 simple CHD cases were enrolled in CHD group, whose average surgery age and follow-up time were （3.0 ±2. 3） years （36 d to 11 years） and （3.6±3.2） （ 0. 5 - 14. 2） years, respectively. The number of cases in 4 agegroups were 39 （3 - 5 years） , 27 （ - 8 years）, 11 （ - 12 years） and 12 （ -15 years）, and were 26, 39, 39 and 29 respectively for the control group. The height, body weight and body mass index （BMI） of the 133 control subjects matched the cases by age groups. （1） The Pwd, QRS duration and QTd tended to decrease after 6MWT but did not reach significant level. （2） The QTd before 6MWT in CHD group was higher than that in the control group by all agegroups, however the difference in the 3 -5 and - 12 agegroups reached significant level [ （0. 025±0. 018） vs （0. 012± 0. 011 ） s, P = 0. 004 ; （0. 029±0. 014） vs （0. 019 ± 0. 012） s, P = 0. 019 ]. No significant difference was observed after 6MWT. And there were no differences after 6MWT（P 〉0. 05）. （2） QRS duration tended to be prolonged after 6MWT, only the difference in -8 and - 15 agegroup reached significant level （P 〈0O. 01 ）. （4）Compared with the simple CHD subgroup, the QRS duration in complex CHD subgroup became wide before [ （0. 102 ± 0. 025 ） vs （0. 080 ± 0. 021 ） s, P = 0. 000 ] and after [ （0. 103 ± 0. 026） vs （0. 080± 0. 021 ） s, P =0. 000] 6MWT. But there were no significant differences in Pwd and QTd before and after 6MWT performed between two subgroups. Conclusions The electric activity was still unstable during mid- or long-term follow-up in children after CHD surgery. The alteration of Pwd, QRS duration and QTd pre- and post-6MWT in postoperative CHD children were consistent with those in healthy children, suggesting that sub-maximal exercise test of 6MWT might improve the stability of heart electric activities.