Clinical Analysis Of 246 Children With Supraventricular Tachycardia

Objective: To explore the clinical features of supraventricular tachycardia(SVT)in children,so as to improve the understanding of SVT.Methods: To retrospectively analyze the clinical data of children hospitalized and diagnosed with SVT in Children's Hospital of Chongqing Medical University from January 2014 to September 2019,including gender,age,age at the onset of tachycardia,clinical manifestations,duration,incentives,etc.,to compare the efficacy of different treatment methods,and to analyze the relevant factors of drug treatment response.Results: A total of 246 children with supraventricular tachycardia were diagnosed,140 cases(56.9%)were male,106 cases(43.0%)were female,the age of first visit was 19.5(1.6,96.0)months(1 day ~16 years),the age of initial onset : 121 cases(49.2%)aged ~1 year,20 cases(8.1%)aged ~3 years,29 cases(11.8%)aged ~6 years,76 cases(30.9%)aged 3 6 years.Only 67 cases(27.2%)had definite inducements,of which 54 cases(80.6%)were induced by respiratory tract infection.The clinical manifestations of SVT in infants and young children are atypical,and older children show palpitations,fatigue,pallor,chest tightness,etc.A total of 411 cardioversions were performed in 246 children,including vagus nerve stimulation in 12 cases(2.9%),intravenous antiarrhythmic drugs in 409 cases(99.5%),electrical cardioversion in 4 cases(1.0%)and radiofrequency ablation in 12 cases(2.9%).The antiarrhythmic sinus turning time of intravenous drugs was: ATP 10(1,30)s,propafenone 6.0(5.0,10.0)min,cedilanid 4.5±6.9 h,amiodarone 10.5±13.4 min,respectively.The complete effective rates were: ATP 69.0%(200/290),propafenone 68.8%(55/80),cedilanid 60.0%(18/30),amiodarone 44.4%(4/9).The complete effective rates of ATP and propafenone were slightly higher than those of cedilanid,but the difference was not statistically significant(c2=1.020,P=0.600).There are no drug-induced cardiac-related serious adverse reactions,and the incidence of minor events were: ATP 13 cases(4.5%),including 6 cases of high value of QT interval,4 cases of sinus bradycardia,3 cases of first-degree atrioventricular block;11 cases of propafenone(13.8%),including 1 case of sinus bradycardia,5 cases of first-degree atrioventricular block,3 cases of QT interval prolongation,and 2cases of high value of QT interval;1 case(3.3%)high value of QT interval of cedilanid and 1 case(11.1%)frequent premature ventricular contractions of amiodarone.The proportion of cardiac-related adverse reactions caused by propafenone was significantly higher than that caused by ATP and cedilanid,and the difference was statistically significant(c2=9.661,P=0.008).There was significant difference in the complete effective rate(48.0% vs 68.0%)between the high dose group(30.2mg/kg,165 cases(56.9%)and the low dose group((27)0.2mg/kg,125 cases(43.1%),The difference was statistically significant(Z=-3.472,P=0.001),while there was no significant difference between the two groups in the time of return to sinus rhythm(10.0(1.5,30.0)and 10.0(1.0,60.0))and the adverse cardiac reactions(6.4% and 3.0%);82 cases failed in ATP treatment were treated with combination therapy,among which 65.7%(46/70)combined with propafenone completely turn into sinus.The complete effective rate of electrical cardioversion was 50.0%(2/2),both of which were medically ineffective and hemodynamically unstable.Between different therapeutic groups,there were statistical differences in the tachycardia duration and whether combined with EF decline(c2=8.766,33.717,P=0.012,0.000),while there were no significant differences in gender,age at onset,congenital heart disease,infection and biochemical abnormalities.Conclusion: Supraventricular tachycardia in children mostly starts in infancy;Respiratory tract infection is the most common cause;ATP is the first choice to stop the episodes;Combination therapy or electrical cardioversion can be used for intractable SVT that is ineffective with a single drug;The response of children to antiarrhythmic drugs was related to SVT duration and heart EF;Radiofrequency ablation is the only radical treatment for recurrent SVT that is ineffective with drug treatment.